Adding upstream version 4:7.4.7.upstream/4%7.4.7upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

36 files changed, 8878 insertions, 0 deletions

diff --git a/sd/source/ui/sidebar/AllMasterPagesSelector.cxx b/sd/source/ui/sidebar/AllMasterPagesSelector.cxx
new file mode 100644
index 000000000..76e056120
--- /dev/null
+++ b/sd/source/ui/sidebar/AllMasterPagesSelector.cxx
@@ -0,0 +1,180 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "AllMasterPagesSelector.hxx"
+#include <ViewShellBase.hxx>
+#include "MasterPageContainer.hxx"
+#include "MasterPageDescriptor.hxx"
+#include <helpids.h>
+
+#include <set>
+
+namespace {
+
+using namespace sd::sidebar;
+
+int GetURLPriority (const SharedMasterPageDescriptor& rpDescriptor)
+{
+    int nPriority (0);
+    switch (rpDescriptor->GetURLClassification())
+    {
+        case MasterPageDescriptor::URLCLASS_USER:         nPriority = 0; break;
+        case MasterPageDescriptor::URLCLASS_LAYOUT:       nPriority = 1; break;
+        case MasterPageDescriptor::URLCLASS_PRESENTATION: nPriority = 2; break;
+        case MasterPageDescriptor::URLCLASS_OTHER:        nPriority = 3; break;
+        case MasterPageDescriptor::URLCLASS_UNKNOWN:      nPriority = 4; break;
+        default:
+        case MasterPageDescriptor::URLCLASS_UNDETERMINED: nPriority = 5; break;
+    }
+    return nPriority;
+}
+
+class MasterPageDescriptorOrder
+{
+public:
+    bool operator() (
+        const SharedMasterPageDescriptor& rp1,
+        const SharedMasterPageDescriptor& rp2) const
+    {
+        if (rp1->meOrigin == MasterPageContainer::DEFAULT)
+            return true;
+        else if (rp2->meOrigin == MasterPageContainer::DEFAULT)
+            return false;
+        else if (rp1->GetURLClassification() == rp2->GetURLClassification())
+            return rp1->mnTemplateIndex < rp2->mnTemplateIndex;
+        else
+            return GetURLPriority(rp1) < GetURLPriority(rp2);
+    }
+};
+
+} // end of anonymous namespace
+
+namespace sd::sidebar {
+
+class AllMasterPagesSelector::SortedMasterPageDescriptorList
+    : public ::std::set<SharedMasterPageDescriptor,MasterPageDescriptorOrder>
+{
+public:
+    SortedMasterPageDescriptorList() {}
+};
+
+std::unique_ptr<PanelLayout> AllMasterPagesSelector::Create (
+    weld::Widget* pParent,
+    ViewShellBase& rViewShellBase,
+    const css::uno::Reference<css::ui::XSidebar>& rxSidebar)
+{
+    SdDrawDocument* pDocument = rViewShellBase.GetDocument();
+    if (pDocument == nullptr)
+        return nullptr;
+
+    auto pContainer = std::make_shared<MasterPageContainer>();
+
+    auto xSelector(std::make_unique<AllMasterPagesSelector>(
+            pParent,
+            *pDocument,
+            rViewShellBase,
+            pContainer,
+            rxSidebar));
+    xSelector->LateInit();
+    xSelector->SetHelpId(HID_SD_TASK_PANE_PREVIEW_ALL);
+
+    return xSelector;
+}
+
+AllMasterPagesSelector::AllMasterPagesSelector (
+    weld::Widget* pParent,
+    SdDrawDocument& rDocument,
+    ViewShellBase& rBase,
+    const std::shared_ptr<MasterPageContainer>& rpContainer,
+    const css::uno::Reference<css::ui::XSidebar>& rxSidebar)
+    : MasterPagesSelector(pParent, rDocument, rBase, rpContainer, rxSidebar, "modules/simpress/ui/masterpagepanelall.ui", "allvalueset"),
+      mpSortedMasterPages(new SortedMasterPageDescriptorList())
+{
+    MasterPagesSelector::Fill();
+}
+
+AllMasterPagesSelector::~AllMasterPagesSelector()
+{
+}
+
+void AllMasterPagesSelector::Fill (ItemList& rItemList)
+{
+    if (mpSortedMasterPages->empty())
+        UpdateMasterPageList();
+    UpdatePageSet(rItemList);
+}
+
+void AllMasterPagesSelector::NotifyContainerChangeEvent (
+    const MasterPageContainerChangeEvent& rEvent)
+{
+    switch (rEvent.meEventType)
+    {
+        case MasterPageContainerChangeEvent::EventType::CHILD_ADDED:
+            AddItem(rEvent.maChildToken);
+            MasterPagesSelector::Fill();
+            break;
+
+        case MasterPageContainerChangeEvent::EventType::INDEX_CHANGED:
+            mpSortedMasterPages->clear();
+            MasterPagesSelector::Fill();
+            break;
+
+        default:
+            MasterPagesSelector::NotifyContainerChangeEvent(rEvent);
+            break;
+    }
+}
+
+void AllMasterPagesSelector::UpdateMasterPageList()
+{
+    mpSortedMasterPages->clear();
+    int nTokenCount = mpContainer->GetTokenCount();
+    for (int i=0; i<nTokenCount; i++)
+        AddItem(mpContainer->GetTokenForIndex(i));
+}
+
+void AllMasterPagesSelector::AddItem (MasterPageContainer::Token aToken)
+{
+    switch (mpContainer->GetOriginForToken(aToken))
+    {
+        case MasterPageContainer::DEFAULT:
+        case MasterPageContainer::TEMPLATE:
+            // Templates are added only when coming from the
+            // MasterPageContainerFiller so that they have an id which
+            // defines their place in the list.  Templates (pre) loaded from
+            // RecentlyUsedMasterPages are ignored (they will be loaded
+            // later by the MasterPageContainerFiller.)
+            if (mpContainer->GetTemplateIndexForToken(aToken) >= 0)
+                mpSortedMasterPages->insert(mpContainer->GetDescriptorForToken(aToken));
+            break;
+
+        default:
+            break;
+    }
+}
+
+void AllMasterPagesSelector::UpdatePageSet (ItemList& rItemList)
+{
+    for (const auto& rxDescriptor : *mpSortedMasterPages)
+        rItemList.push_back(rxDescriptor->maToken);
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/AllMasterPagesSelector.hxx b/sd/source/ui/sidebar/AllMasterPagesSelector.hxx
new file mode 100644
index 000000000..982a2ec52
--- /dev/null
+++ b/sd/source/ui/sidebar/AllMasterPagesSelector.hxx
@@ -0,0 +1,80 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include "MasterPagesSelector.hxx"
+
+#include <memory>
+
+namespace sd::sidebar {
+
+/** Show a list of all available master pages so that the user can assign
+    them to the document.
+*/
+class AllMasterPagesSelector
+    : public MasterPagesSelector
+{
+    friend class VclPtrInstance<AllMasterPagesSelector>;
+public:
+    static std::unique_ptr<PanelLayout> Create (
+        weld::Widget* pParent,
+        ViewShellBase& rViewShellBase,
+        const css::uno::Reference<css::ui::XSidebar>& rxSidebar);
+
+    AllMasterPagesSelector (
+        weld::Widget* pParent,
+        SdDrawDocument& rDocument,
+        ViewShellBase& rBase,
+        const std::shared_ptr<MasterPageContainer>& rpContainer,
+        const css::uno::Reference<css::ui::XSidebar>& rxSidebar);
+    virtual ~AllMasterPagesSelector() override;
+
+
+    /** Scan the set of templates for the ones whose first master pages are
+        shown by this control and store them in the MasterPageContainer.
+    */
+    virtual void Fill (ItemList& rItemList) override;
+
+protected:
+    virtual void NotifyContainerChangeEvent (const MasterPageContainerChangeEvent& rEvent) override;
+
+private:
+    /** The list of master pages displayed by this class.
+    */
+    class SortedMasterPageDescriptorList;
+    ::std::unique_ptr<SortedMasterPageDescriptorList> mpSortedMasterPages;
+
+    void AddItem (MasterPageContainer::Token aToken);
+
+    /** Add all items in the internal master page list into the given list.
+    */
+    void UpdatePageSet (ItemList& rItemList);
+
+    /** Update the internal list of master pages that are to show in the
+        control.
+    */
+    void UpdateMasterPageList();
+
+    using MasterPagesSelector::Fill;
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/CurrentMasterPagesSelector.cxx b/sd/source/ui/sidebar/CurrentMasterPagesSelector.cxx
new file mode 100644
index 000000000..269099edd
--- /dev/null
+++ b/sd/source/ui/sidebar/CurrentMasterPagesSelector.cxx
@@ -0,0 +1,263 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "CurrentMasterPagesSelector.hxx"
+#include "PreviewValueSet.hxx"
+#include <ViewShellBase.hxx>
+#include <DrawViewShell.hxx>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include "MasterPageContainer.hxx"
+#include "MasterPageContainerProviders.hxx"
+#include "MasterPageDescriptor.hxx"
+#include <EventMultiplexer.hxx>
+#include <DrawDocShell.hxx>
+#include <osl/diagnose.h>
+
+#include <helpids.h>
+
+#include <set>
+
+using namespace ::com::sun::star;
+
+namespace sd::sidebar {
+
+std::unique_ptr<PanelLayout> CurrentMasterPagesSelector::Create (
+    weld::Widget* pParent,
+    ViewShellBase& rViewShellBase,
+    const css::uno::Reference<css::ui::XSidebar>& rxSidebar)
+{
+    SdDrawDocument* pDocument = rViewShellBase.GetDocument();
+    if (pDocument == nullptr)
+        return nullptr;
+
+    auto pContainer = std::make_shared<MasterPageContainer>();
+
+    auto xSelector(std::make_unique<CurrentMasterPagesSelector>(
+            pParent,
+            *pDocument,
+            rViewShellBase,
+            pContainer,
+            rxSidebar));
+    xSelector->LateInit();
+    xSelector->SetHelpId( HID_SD_TASK_PANE_PREVIEW_CURRENT );
+
+    return xSelector;
+}
+
+CurrentMasterPagesSelector::CurrentMasterPagesSelector (
+    weld::Widget* pParent,
+    SdDrawDocument& rDocument,
+    ViewShellBase& rBase,
+    const std::shared_ptr<MasterPageContainer>& rpContainer,
+    const css::uno::Reference<css::ui::XSidebar>& rxSidebar)
+    : MasterPagesSelector (pParent, rDocument, rBase, rpContainer, rxSidebar, "modules/simpress/ui/masterpagepanel.ui", "usedvalueset")
+{
+    Link<sd::tools::EventMultiplexerEvent&,void> aLink (LINK(this,CurrentMasterPagesSelector,EventMultiplexerListener));
+    rBase.GetEventMultiplexer()->AddEventListener(aLink);
+}
+
+CurrentMasterPagesSelector::~CurrentMasterPagesSelector()
+{
+    if (mrDocument.GetDocSh() != nullptr)
+    {
+        EndListening(*mrDocument.GetDocSh());
+    }
+    else
+    {
+        OSL_ASSERT(mrDocument.GetDocSh() != nullptr);
+    }
+
+    Link<sd::tools::EventMultiplexerEvent&,void> aLink (LINK(this,CurrentMasterPagesSelector,EventMultiplexerListener));
+    mrBase.GetEventMultiplexer()->RemoveEventListener(aLink);
+}
+
+void CurrentMasterPagesSelector::LateInit()
+{
+    MasterPagesSelector::LateInit();
+    MasterPagesSelector::Fill();
+    if (mrDocument.GetDocSh() != nullptr)
+    {
+        StartListening(*mrDocument.GetDocSh());
+    }
+    else
+    {
+        OSL_ASSERT(mrDocument.GetDocSh() != nullptr);
+    }
+}
+
+void CurrentMasterPagesSelector::Fill (ItemList& rItemList)
+{
+    sal_uInt16 nPageCount = mrDocument.GetMasterSdPageCount(PageKind::Standard);
+    // Remember the names of the master pages that have been inserted to
+    // avoid double insertion.
+    ::std::set<OUString> aMasterPageNames;
+    for (sal_uInt16 nIndex=0; nIndex<nPageCount; nIndex++)
+    {
+        SdPage* pMasterPage = mrDocument.GetMasterSdPage (nIndex, PageKind::Standard);
+        if (pMasterPage == nullptr)
+            continue;
+
+        // Use the name of the master page to avoid duplicate entries.
+        OUString sName (pMasterPage->GetName());
+        if (!aMasterPageNames.insert(sName).second)
+            continue;
+
+        // Look up the master page in the container and, when it is not yet
+        // in it, insert it.
+        MasterPageContainer::Token aToken = mpContainer->GetTokenForPageObject(pMasterPage);
+        if (aToken == MasterPageContainer::NIL_TOKEN)
+        {
+            SharedMasterPageDescriptor pDescriptor = std::make_shared<MasterPageDescriptor>(
+                MasterPageContainer::MASTERPAGE,
+                nIndex,
+                OUString(),
+                pMasterPage->GetName(),
+                OUString(),
+                pMasterPage->IsPrecious(),
+                std::make_shared<ExistingPageProvider>(pMasterPage),
+                std::make_shared<PagePreviewProvider>());
+            aToken = mpContainer->PutMasterPage(pDescriptor);
+        }
+
+        rItemList.push_back(aToken);
+    }
+}
+
+OUString CurrentMasterPagesSelector::GetContextMenuUIFile() const
+{
+    return "modules/simpress/ui/currentmastermenu.ui";
+}
+
+void CurrentMasterPagesSelector::UpdateSelection()
+{
+    // Iterate over all pages and for the selected ones put the name of
+    // their master page into a set.
+    sal_uInt16 nPageCount = mrDocument.GetSdPageCount(PageKind::Standard);
+    ::std::set<OUString> aNames;
+    sal_uInt16 nIndex;
+    bool bLoop (true);
+    for (nIndex=0; nIndex<nPageCount && bLoop; nIndex++)
+    {
+        SdPage* pPage = mrDocument.GetSdPage (nIndex, PageKind::Standard);
+        if (pPage != nullptr && pPage->IsSelected())
+        {
+            if ( ! pPage->TRG_HasMasterPage())
+            {
+                // One of the pages has no master page.  This is an
+                // indicator for that this method is called in the middle of
+                // a document change and that the model is not in a valid
+                // state.  Therefore we stop update the selection and wait
+                // for another call to UpdateSelection when the model is
+                // valid again.
+                bLoop = false;
+            }
+            else
+            {
+                SdrPage& rMasterPage (pPage->TRG_GetMasterPage());
+                assert(dynamic_cast<SdPage*>(&rMasterPage));
+                aNames.insert(static_cast<SdPage&>(rMasterPage).GetName());
+            }
+        }
+    }
+
+    // Find the items for the master pages in the set.
+    sal_uInt16 nItemCount (mxPreviewValueSet->GetItemCount());
+    for (nIndex=1; nIndex<=nItemCount && bLoop; nIndex++)
+    {
+        OUString sName (mxPreviewValueSet->GetItemText (nIndex));
+        if (aNames.find(sName) != aNames.end())
+        {
+            mxPreviewValueSet->SelectItem (nIndex);
+        }
+    }
+}
+
+void CurrentMasterPagesSelector::ExecuteCommand(const OString &rIdent)
+{
+    if (rIdent == "delete")
+    {
+        // Check once again that the master page can safely be deleted,
+        // i.e. is not used.
+        SdPage* pMasterPage = GetSelectedMasterPage();
+        if (pMasterPage != nullptr
+            && mrDocument.GetMasterPageUserCount(pMasterPage) == 0)
+        {
+            // Removing the precious flag so that the following call to
+            // RemoveUnnecessaryMasterPages() will remove this master page.
+            pMasterPage->SetPrecious(false);
+            mrDocument.RemoveUnnecessaryMasterPages(pMasterPage);
+        }
+    }
+    else
+        MasterPagesSelector::ExecuteCommand(rIdent);
+}
+
+void CurrentMasterPagesSelector::ProcessPopupMenu(weld::Menu& rMenu)
+{
+    // Disable the delete entry when there is only one master page.
+    if (mrDocument.GetMasterPageUserCount(GetSelectedMasterPage()) > 0)
+        rMenu.set_sensitive("delete", false);
+
+    std::shared_ptr<DrawViewShell> pDrawViewShell (
+        std::dynamic_pointer_cast<DrawViewShell>(mrBase.GetMainViewShell()));
+    if (pDrawViewShell && pDrawViewShell->GetEditMode() == EditMode::MasterPage)
+    {
+        rMenu.set_sensitive("edit", false);
+    }
+
+    MasterPagesSelector::ProcessPopupMenu(rMenu);
+}
+
+IMPL_LINK(CurrentMasterPagesSelector,EventMultiplexerListener,
+    sd::tools::EventMultiplexerEvent&, rEvent, void)
+{
+    switch (rEvent.meEventId)
+    {
+        case EventMultiplexerEventId::CurrentPageChanged:
+        case EventMultiplexerEventId::EditModeNormal:
+        case EventMultiplexerEventId::EditModeMaster:
+        case EventMultiplexerEventId::SlideSortedSelection:
+            UpdateSelection();
+            break;
+
+        case EventMultiplexerEventId::PageOrder:
+            // This is tricky.  If a master page is removed, moved, or
+            // added we have to wait until both the notes master page
+            // and the standard master page have been removed, moved,
+            // or added.  We do this by looking at the number of master
+            // pages which has to be odd in the consistent state (the
+            // handout master page is always present).  If the number is
+            // even we ignore the hint.
+            if (mrBase.GetDocument()->GetMasterPageCount()%2 == 1)
+                MasterPagesSelector::Fill();
+            break;
+
+        case EventMultiplexerEventId::ShapeChanged:
+        case EventMultiplexerEventId::ShapeInserted:
+        case EventMultiplexerEventId::ShapeRemoved:
+            InvalidatePreview(static_cast<const SdPage*>(rEvent.mpUserData));
+            break;
+        default: break;
+    }
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/CurrentMasterPagesSelector.hxx b/sd/source/ui/sidebar/CurrentMasterPagesSelector.hxx
new file mode 100644
index 000000000..cd7c27734
--- /dev/null
+++ b/sd/source/ui/sidebar/CurrentMasterPagesSelector.hxx
@@ -0,0 +1,77 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <svl/lstner.hxx>
+
+#include "MasterPagesSelector.hxx"
+
+namespace sd::tools { class EventMultiplexerEvent; }
+
+namespace sd::sidebar {
+
+/** Show the master pages currently used by a SdDrawDocument.
+*/
+class CurrentMasterPagesSelector
+    : public MasterPagesSelector,
+      public SfxListener
+{
+    friend class VclPtrInstance<CurrentMasterPagesSelector>;
+public:
+    static std::unique_ptr<PanelLayout> Create (
+        weld::Widget* pParent,
+        ViewShellBase& rViewShellBase,
+        const css::uno::Reference<css::ui::XSidebar>& rxSidebar);
+
+    CurrentMasterPagesSelector (
+        weld::Widget* pParent,
+        SdDrawDocument& rDocument,
+        ViewShellBase& rBase,
+        const std::shared_ptr<MasterPageContainer>& rpContainer,
+        const css::uno::Reference<css::ui::XSidebar>& rxSidebar);
+    virtual ~CurrentMasterPagesSelector() override;
+
+    /** Set the selection so that the master page is selected that is
+        used by the currently selected page of the document in the
+        center pane.
+    */
+    void UpdateSelection();
+
+    /** Copy all master pages that are to be shown into the given list.
+    */
+    virtual void Fill (ItemList& rItemList) override;
+
+    using MasterPagesSelector::Fill;
+
+protected:
+    virtual OUString GetContextMenuUIFile() const override;
+
+    virtual void ProcessPopupMenu(weld::Menu& rMenu) override;
+    virtual void ExecuteCommand(const OString &rIdent) override;
+
+private:
+    virtual void LateInit() override;
+
+    DECL_LINK(EventMultiplexerListener,sd::tools::EventMultiplexerEvent&, void);
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/DocumentHelper.cxx b/sd/source/ui/sidebar/DocumentHelper.cxx
new file mode 100644
index 000000000..00c028868
--- /dev/null
+++ b/sd/source/ui/sidebar/DocumentHelper.cxx
@@ -0,0 +1,536 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "DocumentHelper.hxx"
+
+#include <drawdoc.hxx>
+#include <DrawDocShell.hxx>
+#include <sdpage.hxx>
+#include <glob.hxx>
+#include <unmovss.hxx>
+#include <strings.hrc>
+#include <sdresid.hxx>
+#include <undoback.hxx>
+#include <ViewShell.hxx>
+#include <ViewShellBase.hxx>
+#include <com/sun/star/drawing/XDrawPagesSupplier.hpp>
+#include <com/sun/star/drawing/XDrawPages.hpp>
+#include <stlpool.hxx>
+#include <svx/xfillit0.hxx>
+#include <svx/svdundo.hxx>
+#include <tools/diagnose_ex.h>
+#include <xmloff/autolayout.hxx>
+#include <sal/log.hxx>
+
+using namespace ::com::sun::star;
+
+namespace sd::sidebar {
+
+SdPage* DocumentHelper::CopyMasterPageToLocalDocument (
+    SdDrawDocument& rTargetDocument,
+    SdPage* pMasterPage)
+{
+    SdPage* pNewMasterPage = nullptr;
+
+    do
+    {
+        if (pMasterPage == nullptr)
+            break;
+
+        // Check the presence of the source document.
+        SdDrawDocument& rSourceDocument(static_cast< SdDrawDocument& >(pMasterPage->getSdrModelFromSdrPage()));
+
+        // When the given master page already belongs to the target document
+        // then there is nothing more to do.
+        if (&rSourceDocument == &rTargetDocument)
+        {
+            pNewMasterPage = pMasterPage;
+            break;
+        }
+
+        // Test if the master pages of both the slide and its notes page are
+        // present.  This is not the case when we are called during the
+        // creation of the slide master page because then the notes master
+        // page is not there.
+        sal_uInt16 nSourceMasterPageCount = rSourceDocument.GetMasterPageCount();
+        if (nSourceMasterPageCount%2 == 0)
+            // There should be 1 handout page + n slide masters + n notes
+            // masters = 2*n+1.  An even value indicates that a new slide
+            // master but not yet the notes master has been inserted.
+            break;
+        sal_uInt16 nIndex = pMasterPage->GetPageNum();
+        if (nSourceMasterPageCount <= nIndex+1)
+            break;
+        // Get the slide master page.
+        if (pMasterPage != static_cast<SdPage*>(
+            rSourceDocument.GetMasterPage(nIndex)))
+            break;
+        // Get the notes master page.
+        SdPage* pNotesMasterPage = static_cast<SdPage*>(
+            rSourceDocument.GetMasterPage(nIndex+1));
+        if (pNotesMasterPage == nullptr)
+            break;
+
+        // Check if a master page with the same name as that of the given
+        // master page already exists.
+        bool bPageExists (false);
+        sal_uInt16 nMasterPageCount(rTargetDocument.GetMasterSdPageCount(PageKind::Standard));
+        for (sal_uInt16 nMaster=0; nMaster<nMasterPageCount; nMaster++)
+        {
+            SdPage* pCandidate = rTargetDocument.GetMasterSdPage (nMaster, PageKind::Standard);
+            if (pCandidate->GetName() == pMasterPage->GetName())
+            {
+                bPageExists = true;
+                pNewMasterPage = pCandidate;
+                break;
+            }
+        }
+        if (bPageExists)
+            break;
+
+        // Create a new slide (and its notes page.)
+        uno::Reference<drawing::XDrawPagesSupplier> xSlideSupplier (
+            rTargetDocument.getUnoModel(), uno::UNO_QUERY);
+        if ( ! xSlideSupplier.is())
+            break;
+        uno::Reference<drawing::XDrawPages> xSlides =
+            xSlideSupplier->getDrawPages();
+        if ( ! xSlides.is())
+            break;
+        xSlides->insertNewByIndex (xSlides->getCount());
+
+        // Set a layout.
+        SdPage* pSlide = rTargetDocument.GetSdPage(
+            rTargetDocument.GetSdPageCount(PageKind::Standard)-1,
+            PageKind::Standard);
+        if (pSlide == nullptr)
+            break;
+        pSlide->SetAutoLayout(AUTOLAYOUT_TITLE, true);
+
+        // Create a copy of the master page and the associated notes
+        // master page and insert them into our document.
+        pNewMasterPage = AddMasterPage(rTargetDocument, pMasterPage);
+        if (pNewMasterPage==nullptr)
+            break;
+        SdPage* pNewNotesMasterPage
+            = AddMasterPage(rTargetDocument, pNotesMasterPage);
+        if (pNewNotesMasterPage==nullptr)
+            break;
+
+        // Make the connection from the new slide to the master page
+        // (and do the same for the notes page.)
+        rTargetDocument.SetMasterPage (
+            rTargetDocument.GetSdPageCount(PageKind::Standard)-1,
+            pNewMasterPage->GetName(),
+            &rTargetDocument,
+            false, // Connect the new master page with the new slide but
+                   // do not modify other (master) pages.
+            true);
+    }
+    while (false);
+
+    // We are not interested in any automatisms for our modified internal
+    // document.
+    rTargetDocument.SetChanged(false);
+
+    return pNewMasterPage;
+}
+
+SdPage* DocumentHelper::GetSlideForMasterPage (SdPage const * pMasterPage)
+{
+    SdPage* pCandidate = nullptr;
+
+    SdDrawDocument* pDocument = nullptr;
+    if (pMasterPage != nullptr)
+        pDocument = dynamic_cast< SdDrawDocument* >(&pMasterPage->getSdrModelFromSdrPage());
+
+    // Iterate over all pages and check if it references the given master
+    // page.
+    if (pDocument!=nullptr && pDocument->GetSdPageCount(PageKind::Standard) > 0)
+    {
+        // In most cases a new slide has just been inserted so start with
+        // the last page.
+        sal_uInt16 nPageIndex (pDocument->GetSdPageCount(PageKind::Standard)-1);
+        bool bFound (false);
+        while ( ! bFound)
+        {
+            pCandidate = pDocument->GetSdPage(
+                nPageIndex,
+                PageKind::Standard);
+            if (pCandidate != nullptr)
+            {
+                if (static_cast<SdPage*>(&pCandidate->TRG_GetMasterPage())
+                    == pMasterPage)
+                {
+                    bFound = true;
+                    break;
+                }
+            }
+
+            if (nPageIndex == 0)
+                break;
+            else
+                nPageIndex --;
+        }
+
+        // If no page was found, that referenced the given master page, reset
+        // the pointer that is returned.
+        if ( ! bFound)
+            pCandidate = nullptr;
+    }
+
+    return pCandidate;
+}
+
+SdPage* DocumentHelper::AddMasterPage (
+    SdDrawDocument& rTargetDocument,
+    SdPage const * pMasterPage)
+{
+    rtl::Reference<SdPage> pClonedMasterPage;
+
+    if (pMasterPage!=nullptr)
+    {
+        try
+        {
+            // Duplicate the master page.
+            pClonedMasterPage = static_cast<SdPage*>(pMasterPage->CloneSdrPage(rTargetDocument).get());
+
+            // Copy the necessary styles.
+            SdDrawDocument& rSourceDocument(static_cast< SdDrawDocument& >(pMasterPage->getSdrModelFromSdrPage()));
+            ProvideStyles(rSourceDocument, rTargetDocument, pClonedMasterPage.get());
+
+            // Copy the precious flag.
+            pClonedMasterPage->SetPrecious(pMasterPage->IsPrecious());
+
+            // Now that the styles are available we can insert the cloned
+            // master page.
+            rTargetDocument.InsertMasterPage (pClonedMasterPage.get());
+        }
+        catch(const uno::Exception&)
+        {
+            DBG_UNHANDLED_EXCEPTION("sd");
+            pClonedMasterPage = nullptr;
+        }
+        catch(const ::std::exception& e)
+        {
+            pClonedMasterPage = nullptr;
+            SAL_WARN("sd", "caught general exception " << e.what());
+        }
+        catch(...)
+        {
+            pClonedMasterPage = nullptr;
+            SAL_WARN("sd", "caught general exception");
+        }
+    }
+
+    return pClonedMasterPage.get();
+}
+
+void DocumentHelper::ProvideStyles (
+    SdDrawDocument const & rSourceDocument,
+    SdDrawDocument& rTargetDocument,
+    SdPage const * pPage)
+{
+    // Get the layout name of the given page.
+    OUString sLayoutName (pPage->GetLayoutName());
+    sal_Int32 nIndex = sLayoutName.indexOf(SD_LT_SEPARATOR);
+    if( nIndex != -1 )
+        sLayoutName = sLayoutName.copy(0, nIndex);
+
+    // Copy the style sheet from source to target document.
+    SdStyleSheetPool* pSourceStyleSheetPool =
+        static_cast<SdStyleSheetPool*>(rSourceDocument.GetStyleSheetPool());
+    SdStyleSheetPool* pTargetStyleSheetPool =
+        static_cast<SdStyleSheetPool*>(rTargetDocument.GetStyleSheetPool());
+    StyleSheetCopyResultVector aCreatedStyles;
+    pTargetStyleSheetPool->CopyLayoutSheets (
+        sLayoutName,
+        *pSourceStyleSheetPool,
+        aCreatedStyles);
+
+    // Add an undo action for the copied style sheets.
+    if( !aCreatedStyles.empty() )
+    {
+        SfxUndoManager* pUndoManager = rTargetDocument.GetDocSh()->GetUndoManager();
+        if (pUndoManager != nullptr)
+        {
+            pUndoManager->AddUndoAction (
+               std::make_unique<SdMoveStyleSheetsUndoAction>(
+                   &rTargetDocument,
+                   aCreatedStyles,
+                   true));
+        }
+    }
+}
+
+void DocumentHelper::AssignMasterPageToPageList (
+    SdDrawDocument& rTargetDocument,
+    SdPage* pMasterPage,
+    const std::shared_ptr<std::vector<SdPage*> >& rpPageList)
+{
+    if (pMasterPage == nullptr || !pMasterPage->IsMasterPage())
+        return;
+
+    // Make the layout name by stripping out the layout postfix from the
+    // layout name of the given master page.
+    OUString sFullLayoutName(pMasterPage->GetLayoutName());
+    OUString sBaseLayoutName (sFullLayoutName);
+    sal_Int32 nIndex = sBaseLayoutName.indexOf(SD_LT_SEPARATOR);
+    if( nIndex != -1 )
+        sBaseLayoutName = sBaseLayoutName.copy(0, nIndex);
+
+    if (rpPageList->empty())
+        return;
+
+    // Create a second list that contains only the valid pointers to
+    // pages for which an assignment is necessary.
+    ::std::vector<SdPage*> aCleanedList;
+    for (const auto& rpPage : *rpPageList)
+    {
+        OSL_ASSERT(rpPage!=nullptr && &rpPage->getSdrModelFromSdrPage() == &rTargetDocument);
+        if (rpPage != nullptr && rpPage->GetLayoutName() != sFullLayoutName)
+        {
+            aCleanedList.push_back(rpPage);
+        }
+    }
+    if (aCleanedList.empty() )
+        return;
+
+    ViewShellId  nViewShellId(-1);
+    if (sd::ViewShell* pViewShell = rTargetDocument.GetDocSh()->GetViewShell())
+        nViewShellId = pViewShell->GetViewShellBase().GetViewShellId();
+    SfxUndoManager* pUndoMgr = rTargetDocument.GetDocSh()->GetUndoManager();
+    if( pUndoMgr )
+        pUndoMgr->EnterListAction(SdResId(STR_UNDO_SET_PRESLAYOUT), OUString(), 0, nViewShellId);
+
+    SdPage* pMasterPageInDocument = ProvideMasterPage(rTargetDocument,pMasterPage,rpPageList);
+    if (pMasterPageInDocument == nullptr)
+        return;
+
+    // Assign the master pages to the given list of pages.
+    for (const auto& rpPage : aCleanedList)
+    {
+        AssignMasterPageToPage (
+            pMasterPageInDocument,
+            sBaseLayoutName,
+            rpPage);
+    }
+
+    if( pUndoMgr )
+        pUndoMgr->LeaveListAction();
+}
+
+SdPage* DocumentHelper::AddMasterPage (
+    SdDrawDocument& rTargetDocument,
+    SdPage const * pMasterPage,
+    sal_uInt16 nInsertionIndex)
+{
+    rtl::Reference<SdPage> pClonedMasterPage;
+
+    if (pMasterPage!=nullptr)
+    {
+        // Duplicate the master page.
+        pClonedMasterPage = static_cast<SdPage*>(pMasterPage->CloneSdrPage(rTargetDocument).get());
+
+        // Copy the precious flag.
+        pClonedMasterPage->SetPrecious(pMasterPage->IsPrecious());
+
+        // Copy the necessary styles.
+        SdDrawDocument& rSourceDocument(static_cast< SdDrawDocument& >(pMasterPage->getSdrModelFromSdrPage()));
+        ProvideStyles(rSourceDocument, rTargetDocument, pClonedMasterPage.get());
+
+        // Now that the styles are available we can insert the cloned
+        // master page.
+        rTargetDocument.InsertMasterPage (pClonedMasterPage.get(), nInsertionIndex);
+
+        // Adapt the size of the new master page to that of the pages in
+        // the document.
+        Size aNewSize (rTargetDocument.GetSdPage(0, pMasterPage->GetPageKind())->GetSize());
+        ::tools::Rectangle aBorders (
+            pClonedMasterPage->GetLeftBorder(),
+            pClonedMasterPage->GetUpperBorder(),
+            pClonedMasterPage->GetRightBorder(),
+            pClonedMasterPage->GetLowerBorder());
+        pClonedMasterPage->ScaleObjects(aNewSize, aBorders, true);
+        pClonedMasterPage->SetSize(aNewSize);
+        pClonedMasterPage->CreateTitleAndLayout(true);
+    }
+
+    return pClonedMasterPage.get();
+}
+
+/** In here we have to handle three cases:
+    1. pPage is a normal slide.  We can use SetMasterPage to assign the
+    master pages to it.
+    2. pPage is a master page that is used by at least one slide.  We can
+    assign the master page to these slides.
+    3. pPage is a master page that is currently not used by any slide.
+    We can delete that page and add copies of the given master pages
+    instead.
+
+    For points 2 and 3 where one master page A is assigned to another B we have
+    to keep in mind that the master page that page A has already been
+    inserted into the target document.
+*/
+void DocumentHelper::AssignMasterPageToPage (
+    SdPage const * pMasterPage,
+    std::u16string_view rsBaseLayoutName,
+    SdPage* pPage)
+{
+    // Leave early when the parameters are invalid.
+    if (pPage == nullptr || pMasterPage == nullptr)
+        return;
+
+    SdDrawDocument& rDocument(dynamic_cast< SdDrawDocument& >(pPage->getSdrModelFromSdrPage()));
+
+    if ( ! pPage->IsMasterPage())
+    {
+        // 1. Remove the background object (so that, if it exists, does
+        // not override the new master page) and assign the master page to
+        // the regular slide.
+        rDocument.GetDocSh()->GetUndoManager()->AddUndoAction(
+            std::make_unique<SdBackgroundObjUndoAction>(
+                rDocument, *pPage, pPage->getSdrPageProperties().GetItemSet()),
+                true);
+        pPage->getSdrPageProperties().PutItem(XFillStyleItem(drawing::FillStyle_NONE));
+
+        rDocument.SetMasterPage (
+            (pPage->GetPageNum()-1)/2,
+            rsBaseLayoutName,
+            &rDocument,
+            false,
+            false);
+    }
+    else
+    {
+        // Find first slide that uses the master page.
+        SdPage* pSlide = nullptr;
+        sal_uInt16 nPageCount = rDocument.GetSdPageCount(PageKind::Standard);
+        for (sal_uInt16 nPage=0; nPage<nPageCount&&pSlide==nullptr; nPage++)
+        {
+            SdrPage* pCandidate = rDocument.GetSdPage(nPage,PageKind::Standard);
+            if (pCandidate != nullptr
+                && pCandidate->TRG_HasMasterPage()
+                && &(pCandidate->TRG_GetMasterPage()) == pPage)
+            {
+                pSlide = static_cast<SdPage*>(pCandidate);
+            }
+        }
+
+        if (pSlide != nullptr)
+        {
+            // 2. Assign the given master pages to the first slide that was
+            // found above that uses the master page.
+            rDocument.SetMasterPage (
+                (pSlide->GetPageNum()-1)/2,
+                rsBaseLayoutName,
+                &rDocument,
+                false,
+                false);
+        }
+        else
+        {
+            // 3. Replace the master page A by a copy of the given master
+            // page B.
+            rDocument.RemoveUnnecessaryMasterPages (
+                pPage);
+        }
+    }
+}
+
+SdPage* DocumentHelper::ProvideMasterPage (
+    SdDrawDocument& rTargetDocument,
+    SdPage* pMasterPage,
+    const std::shared_ptr<std::vector<SdPage*> >& rpPageList)
+{
+    // Make sure that both the master page and its notes master exist
+    // in the source document.  If one is missing then return without
+    // making any changes.
+    if (pMasterPage == nullptr)
+    {
+        // The caller should make sure that the master page is valid.
+        OSL_ASSERT(pMasterPage != nullptr);
+        return nullptr;
+    }
+    SdDrawDocument& rSourceDocument(static_cast< SdDrawDocument& >(pMasterPage->getSdrModelFromSdrPage()));
+    SdPage* pNotesMasterPage = static_cast<SdPage*>(
+        rSourceDocument.GetMasterPage(pMasterPage->GetPageNum()+1));
+    if (pNotesMasterPage == nullptr)
+    {
+        // The model is not in a valid state.  Maybe a new master page
+        // is being (not finished yet) created?  Return without making
+        // any changes.
+        return nullptr;
+    }
+
+    SdPage* pMasterPageInDocument = nullptr;
+    // Search for a master page with the same name as the given one in
+    // the target document.
+    const OUString sMasterPageLayoutName (pMasterPage->GetLayoutName());
+    for (sal_uInt16 nIndex=0,nCount=rTargetDocument.GetMasterPageCount(); nIndex<nCount; ++nIndex)
+    {
+        SdPage* pCandidate = static_cast<SdPage*>(rTargetDocument.GetMasterPage(nIndex));
+        if (pCandidate && sMasterPageLayoutName == pCandidate->GetLayoutName())
+        {
+            // The requested master page does already exist in the
+            // target document, return it.
+            return pCandidate;
+        }
+    }
+
+    // The given master page does not already belong to the target
+    // document so we have to create copies and insert them into the
+    // target document.
+
+    // Determine the position where the new master pages are inserted.
+    // By default they are inserted at the end.  When we assign to a
+    // master page then insert after the last of the (selected) pages.
+    sal_uInt16 nInsertionIndex = rTargetDocument.GetMasterPageCount();
+    if (rpPageList->front()->IsMasterPage())
+    {
+        nInsertionIndex = rpPageList->back()->GetPageNum();
+    }
+
+    // Clone the master page.
+    if (&pMasterPage->getSdrModelFromSdrPage() != &rTargetDocument)
+    {
+        pMasterPageInDocument = AddMasterPage (rTargetDocument, pMasterPage, nInsertionIndex);
+        if( rTargetDocument.IsUndoEnabled() )
+                rTargetDocument.AddUndo(
+                    rTargetDocument.GetSdrUndoFactory().CreateUndoNewPage(*pMasterPageInDocument));
+    }
+    else
+        pMasterPageInDocument = pMasterPage;
+
+    // Clone the notes master.
+    if (&pNotesMasterPage->getSdrModelFromSdrPage() != &rTargetDocument)
+    {
+        SdPage* pClonedNotesMasterPage
+            = AddMasterPage (rTargetDocument, pNotesMasterPage, nInsertionIndex+1);
+        if( rTargetDocument.IsUndoEnabled() )
+            rTargetDocument.AddUndo(
+                rTargetDocument.GetSdrUndoFactory().CreateUndoNewPage(*pClonedNotesMasterPage));
+    }
+
+    return pMasterPageInDocument;
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/DocumentHelper.hxx b/sd/source/ui/sidebar/DocumentHelper.hxx
new file mode 100644
index 000000000..61ba5f810
--- /dev/null
+++ b/sd/source/ui/sidebar/DocumentHelper.hxx
@@ -0,0 +1,108 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sal/config.h>
+#include <sal/types.h>
+
+#include <memory>
+#include <string_view>
+#include <vector>
+
+class SdDrawDocument;
+class SdPage;
+
+namespace sd::sidebar {
+
+/** A collection of methods supporting the handling of master pages.
+*/
+class DocumentHelper
+{
+public:
+    /** Return a copy of the given master page in the given document.
+    */
+    static SdPage* CopyMasterPageToLocalDocument (
+        SdDrawDocument& rTargetDocument,
+        SdPage* pMasterPage);
+
+    /** Return and, when not yet present, create a slide that uses the given
+        master page.
+    */
+    static SdPage* GetSlideForMasterPage (SdPage const * pMasterPage);
+
+    /** Copy the styles used by the given page from the source document to
+        the target document.
+    */
+    static void ProvideStyles (
+        SdDrawDocument const & rSourceDocument,
+        SdDrawDocument& rTargetDocument,
+        SdPage const * pPage);
+
+    /** Assign the given master page to the list of pages.
+        @param rTargetDocument
+            The document that is the owner of the pages in rPageList.
+        @param pMasterPage
+            This master page will usually be a member of the list of all
+            available master pages as provided by the MasterPageContainer.
+        @param rPageList
+            The pages to which to assign the master page.  These pages may
+            be slides or master pages themselves.
+    */
+    static void AssignMasterPageToPageList (
+        SdDrawDocument& rTargetDocument,
+        SdPage* pMasterPage,
+        const std::shared_ptr<std::vector<SdPage*> >& rPageList);
+
+private:
+    static SdPage* AddMasterPage (
+        SdDrawDocument& rTargetDocument,
+        SdPage const * pMasterPage);
+    static SdPage* AddMasterPage (
+        SdDrawDocument& rTargetDocument,
+        SdPage const * pMasterPage,
+        sal_uInt16 nInsertionIndex);
+    static SdPage* ProvideMasterPage (
+        SdDrawDocument& rTargetDocument,
+        SdPage* pMasterPage,
+        const std::shared_ptr<std::vector<SdPage*> >& rpPageList);
+
+    /** Assign the given master page to the given page.
+        @param pMasterPage
+            In contrast to AssignMasterPageToPageList() this page is assumed
+            to be in the target document, i.e. the same document that pPage
+            is in.  The caller will usually call AddMasterPage() to create a
+            clone of a master page in another document to create it.
+        @param rsBaseLayoutName
+            The layout name of the given master page.  It is given so that
+            it has not to be created on every call.  It could be generated
+            from the given master page, though.
+        @param pPage
+            The page to which to assign the master page.  It can be a slide
+            or a master page itself.
+    */
+    static void AssignMasterPageToPage (
+        SdPage const * pMasterPage,
+        std::u16string_view rsBaseLayoutName,
+        SdPage* pPage);
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/IDisposable.hxx b/sd/source/ui/sidebar/IDisposable.hxx
new file mode 100644
index 000000000..e2c1afe27
--- /dev/null
+++ b/sd/source/ui/sidebar/IDisposable.hxx
@@ -0,0 +1,31 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#pragma once
+
+namespace sd::sidebar
+{
+class IDisposable
+{
+public:
+    virtual ~IDisposable();
+};
+
+} // end of namespace ::sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/ISidebarReceiver.hxx b/sd/source/ui/sidebar/ISidebarReceiver.hxx
new file mode 100644
index 000000000..bf51cbe12
--- /dev/null
+++ b/sd/source/ui/sidebar/ISidebarReceiver.hxx
@@ -0,0 +1,31 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#pragma once
+
+namespace sd::sidebar
+{
+class ISidebarReceiver
+{
+public:
+    virtual ~ISidebarReceiver();
+};
+
+} // end of namespace ::sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/LayoutMenu.cxx b/sd/source/ui/sidebar/LayoutMenu.cxx
new file mode 100644
index 000000000..23521df0e
--- /dev/null
+++ b/sd/source/ui/sidebar/LayoutMenu.cxx
@@ -0,0 +1,728 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "LayoutMenu.hxx"
+
+#include <app.hrc>
+#include <drawdoc.hxx>
+#include <framework/FrameworkHelper.hxx>
+#include <strings.hrc>
+#include <helpids.h>
+#include <pres.hxx>
+#include <sdmod.hxx>
+
+#include <sdpage.hxx>
+#include <sdresid.hxx>
+#include <unokywds.hxx>
+#include <bitmaps.hlst>
+#include <tools/gen.hxx>
+#include <tools/SlotStateListener.hxx>
+#include <DrawController.hxx>
+#include <DrawDocShell.hxx>
+#include <DrawViewShell.hxx>
+#include <EventMultiplexer.hxx>
+#include <SlideSorterViewShell.hxx>
+#include <ViewShellBase.hxx>
+#include <sfx2/sidebar/Theme.hxx>
+#include <sal/log.hxx>
+
+#include <comphelper/processfactory.hxx>
+#include <sfx2/dispatch.hxx>
+#include <sfx2/request.hxx>
+#include <sfx2/viewfrm.hxx>
+#include <svl/cjkoptions.hxx>
+#include <svl/stritem.hxx>
+#include <svl/intitem.hxx>
+#include <vcl/commandevent.hxx>
+#include <vcl/image.hxx>
+#include <xmloff/autolayout.hxx>
+
+#include <com/sun/star/drawing/framework/XControllerManager.hpp>
+#include <com/sun/star/drawing/framework/XView.hpp>
+#include <com/sun/star/drawing/framework/ResourceId.hpp>
+
+#include <vector>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::text;
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star::drawing::framework;
+using namespace ::sd::slidesorter;
+using ::sd::framework::FrameworkHelper;
+
+namespace sd::sidebar {
+
+namespace {
+
+struct snew_slide_value_info
+{
+    rtl::OUStringConstExpr msBmpResId;
+    TranslateId mpStrResId;
+    WritingMode meWritingMode;
+    AutoLayout maAutoLayout;
+};
+
+}
+
+constexpr OUStringLiteral EMPTY = u"";
+
+const snew_slide_value_info notes[] =
+{
+    {BMP_SLIDEN_01, STR_AUTOLAYOUT_NOTES, WritingMode_LR_TB,
+     AUTOLAYOUT_NOTES},
+    {EMPTY, {}, WritingMode_LR_TB, AUTOLAYOUT_NONE},
+};
+
+const snew_slide_value_info handout[] =
+{
+    {BMP_SLIDEH_01, STR_AUTOLAYOUT_HANDOUT1, WritingMode_LR_TB,
+     AUTOLAYOUT_HANDOUT1},
+    {BMP_SLIDEH_02, STR_AUTOLAYOUT_HANDOUT2, WritingMode_LR_TB,
+     AUTOLAYOUT_HANDOUT2},
+    {BMP_SLIDEH_03, STR_AUTOLAYOUT_HANDOUT3, WritingMode_LR_TB,
+     AUTOLAYOUT_HANDOUT3},
+    {BMP_SLIDEH_04, STR_AUTOLAYOUT_HANDOUT4, WritingMode_LR_TB,
+     AUTOLAYOUT_HANDOUT4},
+    {BMP_SLIDEH_06, STR_AUTOLAYOUT_HANDOUT6, WritingMode_LR_TB,
+     AUTOLAYOUT_HANDOUT6},
+    {BMP_SLIDEH_09, STR_AUTOLAYOUT_HANDOUT9, WritingMode_LR_TB,
+     AUTOLAYOUT_HANDOUT9},
+    {EMPTY, {}, WritingMode_LR_TB, AUTOLAYOUT_NONE},
+};
+
+const snew_slide_value_info standard[] =
+{
+    {BMP_LAYOUT_EMPTY, STR_AUTOLAYOUT_NONE, WritingMode_LR_TB,        AUTOLAYOUT_NONE},
+    {BMP_LAYOUT_HEAD03, STR_AUTOLAYOUT_TITLE, WritingMode_LR_TB,       AUTOLAYOUT_TITLE},
+    {BMP_LAYOUT_HEAD02, STR_AUTOLAYOUT_CONTENT, WritingMode_LR_TB,        AUTOLAYOUT_TITLE_CONTENT},
+    {BMP_LAYOUT_HEAD02A, STR_AUTOLAYOUT_2CONTENT, WritingMode_LR_TB,       AUTOLAYOUT_TITLE_2CONTENT},
+    {BMP_LAYOUT_HEAD01, STR_AUTOLAYOUT_ONLY_TITLE, WritingMode_LR_TB,  AUTOLAYOUT_TITLE_ONLY},
+    {BMP_LAYOUT_TEXTONLY, STR_AUTOLAYOUT_ONLY_TEXT, WritingMode_LR_TB,   AUTOLAYOUT_ONLY_TEXT},
+    {BMP_LAYOUT_HEAD03B, STR_AUTOLAYOUT_2CONTENT_CONTENT, WritingMode_LR_TB,    AUTOLAYOUT_TITLE_2CONTENT_CONTENT},
+    {BMP_LAYOUT_HEAD03C, STR_AUTOLAYOUT_CONTENT_2CONTENT, WritingMode_LR_TB,    AUTOLAYOUT_TITLE_CONTENT_2CONTENT},
+    {BMP_LAYOUT_HEAD03A, STR_AUTOLAYOUT_2CONTENT_OVER_CONTENT,WritingMode_LR_TB, AUTOLAYOUT_TITLE_2CONTENT_OVER_CONTENT},
+    {BMP_LAYOUT_HEAD02B, STR_AUTOLAYOUT_CONTENT_OVER_CONTENT, WritingMode_LR_TB, AUTOLAYOUT_TITLE_CONTENT_OVER_CONTENT},
+    {BMP_LAYOUT_HEAD04, STR_AUTOLAYOUT_4CONTENT, WritingMode_LR_TB,        AUTOLAYOUT_TITLE_4CONTENT},
+    {BMP_LAYOUT_HEAD06, STR_AUTOLAYOUT_6CONTENT, WritingMode_LR_TB,    AUTOLAYOUT_TITLE_6CONTENT},
+
+    // vertical
+    {BMP_LAYOUT_VERTICAL02, STR_AL_VERT_TITLE_TEXT_CHART, WritingMode_TB_RL, AUTOLAYOUT_VTITLE_VCONTENT_OVER_VCONTENT},
+    {BMP_LAYOUT_VERTICAL01, STR_AL_VERT_TITLE_VERT_OUTLINE, WritingMode_TB_RL, AUTOLAYOUT_VTITLE_VCONTENT},
+    {BMP_LAYOUT_HEAD02, STR_AL_TITLE_VERT_OUTLINE, WritingMode_TB_RL, AUTOLAYOUT_TITLE_VCONTENT},
+    {BMP_LAYOUT_HEAD02A, STR_AL_TITLE_VERT_OUTLINE_CLIPART,   WritingMode_TB_RL, AUTOLAYOUT_TITLE_2VTEXT},
+    {EMPTY, {}, WritingMode_LR_TB, AUTOLAYOUT_NONE}
+};
+
+class LayoutValueSet : public ValueSet
+{
+private:
+    LayoutMenu& mrMenu;
+
+    /** Calculate the number of displayed rows.  This depends on the given
+        item size, the given number of columns, and the size of the
+        control.  Note that this is not the number of rows managed by the
+        valueset.  This number may be larger.  In that case a vertical
+        scroll bar is displayed.
+    */
+    int CalculateRowCount(const Size& rItemSize, int nColumnCount);
+
+public:
+    LayoutValueSet(LayoutMenu& rMenu)
+        : ValueSet(nullptr)
+        , mrMenu(rMenu)
+    {
+    }
+
+    virtual void Resize() override;
+
+    virtual bool Command(const CommandEvent& rEvent) override;
+};
+
+LayoutMenu::LayoutMenu (
+    weld::Widget* pParent,
+    ViewShellBase& rViewShellBase,
+    const css::uno::Reference<css::ui::XSidebar>& rxSidebar)
+    : PanelLayout( pParent, "LayoutPanel", "modules/simpress/ui/layoutpanel.ui" ),
+      mrBase(rViewShellBase),
+      mxLayoutValueSet(new LayoutValueSet(*this)),
+      mxLayoutValueSetWin(new weld::CustomWeld(*m_xBuilder, "layoutvalueset", *mxLayoutValueSet)),
+      mbIsMainViewChangePending(false),
+      mxSidebar(rxSidebar),
+      mbIsDisposed(false)
+{
+    implConstruct( *mrBase.GetDocument()->GetDocSh() );
+    SAL_INFO("sd.ui", "created LayoutMenu at " << this);
+
+    mxLayoutValueSet->SetStyle(mxLayoutValueSet->GetStyle() | WB_ITEMBORDER | WB_FLATVALUESET | WB_TABSTOP);
+
+    mxLayoutValueSet->SetColor(sfx2::sidebar::Theme::GetColor(sfx2::sidebar::Theme::Color_PanelBackground));
+}
+
+void LayoutMenu::implConstruct( DrawDocShell& rDocumentShell )
+{
+    OSL_ENSURE( mrBase.GetDocument()->GetDocSh() == &rDocumentShell,
+        "LayoutMenu::implConstruct: hmm?" );
+    // if this fires, then my assumption that the rDocumentShell parameter to our first ctor is superfluous ...
+    (void) rDocumentShell;
+
+    mxLayoutValueSet->SetStyle (
+        ( mxLayoutValueSet->GetStyle()  & ~(WB_ITEMBORDER) )
+        | WB_TABSTOP
+        | WB_MENUSTYLEVALUESET
+        | WB_NO_DIRECTSELECT
+        );
+    mxLayoutValueSet->SetExtraSpacing(2);
+    mxLayoutValueSet->SetSelectHdl (LINK(this, LayoutMenu, ClickHandler));
+    InvalidateContent();
+
+    Link<::sd::tools::EventMultiplexerEvent&,void> aEventListenerLink (LINK(this,LayoutMenu,EventMultiplexerListener));
+    mrBase.GetEventMultiplexer()->AddEventListener(aEventListenerLink);
+
+    mxLayoutValueSet->SetHelpId(HID_SD_TASK_PANE_PREVIEW_LAYOUTS);
+    mxLayoutValueSet->SetAccessibleName(SdResId(STR_TASKPANEL_LAYOUT_MENU_TITLE));
+
+    Link<const OUString&,void> aStateChangeLink (LINK(this,LayoutMenu,StateChangeHandler));
+    mxListener = new ::sd::tools::SlotStateListener(
+        aStateChangeLink,
+        Reference<frame::XDispatchProvider>(mrBase.GetController()->getFrame(), UNO_QUERY),
+        ".uno:VerticalTextState");
+}
+
+LayoutMenu::~LayoutMenu()
+{
+    SAL_INFO("sd.ui", "destroying LayoutMenu at " << this);
+    Dispose();
+    mxLayoutValueSetWin.reset();
+    mxLayoutValueSet.reset();
+}
+
+void LayoutMenu::Dispose()
+{
+    if (mbIsDisposed)
+        return;
+
+    SAL_INFO("sd.ui", "disposing LayoutMenu at " << this);
+
+    mbIsDisposed = true;
+
+    Reference<lang::XComponent> xComponent (mxListener, UNO_QUERY);
+    if (xComponent.is())
+        xComponent->dispose();
+
+    Clear();
+    Link<tools::EventMultiplexerEvent&,void> aLink (LINK(this,LayoutMenu,EventMultiplexerListener));
+    mrBase.GetEventMultiplexer()->RemoveEventListener (aLink);
+}
+
+AutoLayout LayoutMenu::GetSelectedAutoLayout() const
+{
+    AutoLayout aResult = AUTOLAYOUT_NONE;
+
+    if (!mxLayoutValueSet->IsNoSelection() && mxLayoutValueSet->GetSelectedItemId()!=0)
+    {
+        AutoLayout* pLayout = static_cast<AutoLayout*>(mxLayoutValueSet->GetItemData(mxLayoutValueSet->GetSelectedItemId()));
+        if (pLayout != nullptr)
+            aResult = *pLayout;
+    }
+
+    return aResult;
+}
+
+ui::LayoutSize LayoutMenu::GetHeightForWidth (const sal_Int32 nWidth)
+{
+    sal_Int32 nPreferredHeight = 200;
+    if (mxLayoutValueSet->GetItemCount()>0)
+    {
+        Image aImage = mxLayoutValueSet->GetItemImage(mxLayoutValueSet->GetItemId(0));
+        Size aItemSize = mxLayoutValueSet->CalcItemSizePixel(aImage.GetSizePixel());
+        if (nWidth>0 && aItemSize.Width()>0)
+        {
+            aItemSize.AdjustWidth(8 );
+            aItemSize.AdjustHeight(8 );
+            int nColumnCount = nWidth / aItemSize.Width();
+            if (nColumnCount <= 0)
+                nColumnCount = 1;
+            else if (nColumnCount > 4)
+                nColumnCount = 4;
+            int nRowCount = (mxLayoutValueSet->GetItemCount() + nColumnCount-1) / nColumnCount;
+            nPreferredHeight = nRowCount * aItemSize.Height();
+        }
+    }
+    return ui::LayoutSize(nPreferredHeight,nPreferredHeight,nPreferredHeight);
+}
+
+void LayoutValueSet::Resize()
+{
+    Size aWindowSize = GetOutputSizePixel();
+    if (IsVisible() && aWindowSize.Width() > 0)
+    {
+        // Calculate the number of rows and columns.
+        if (GetItemCount() > 0)
+        {
+            Image aImage = GetItemImage(GetItemId(0));
+            Size aItemSize = CalcItemSizePixel (
+                aImage.GetSizePixel());
+            aItemSize.AdjustWidth(8 );
+            aItemSize.AdjustHeight(8 );
+            int nColumnCount = aWindowSize.Width() / aItemSize.Width();
+            if (nColumnCount < 1)
+                nColumnCount = 1;
+            else if (nColumnCount > 4)
+                nColumnCount = 4;
+
+            int nRowCount = CalculateRowCount (aItemSize, nColumnCount);
+
+            SetColCount(nColumnCount);
+            SetLineCount(nRowCount);
+        }
+    }
+
+    ValueSet::Resize();
+}
+
+bool LayoutValueSet::Command(const CommandEvent& rEvent)
+{
+    if (rEvent.GetCommand() != CommandEventId::ContextMenu)
+        return false;
+
+    // As a preparation for the context menu the item under the mouse is
+    // selected.
+    if (rEvent.IsMouseEvent())
+    {
+        sal_uInt16 nIndex = GetItemId(rEvent.GetMousePosPixel());
+        if (nIndex > 0)
+            SelectItem(nIndex);
+    }
+
+    mrMenu.ShowContextMenu(rEvent.IsMouseEvent() ? &rEvent.GetMousePosPixel() : nullptr);
+    return true;
+}
+
+void LayoutMenu::InsertPageWithLayout (AutoLayout aLayout)
+{
+    ViewShell* pViewShell = mrBase.GetMainViewShell().get();
+    if (pViewShell == nullptr)
+        return;
+
+    SfxViewFrame* pViewFrame = mrBase.GetViewFrame();
+    if (pViewFrame == nullptr)
+        return;
+
+    SfxDispatcher* pDispatcher = pViewFrame->GetDispatcher();
+    if (pDispatcher == nullptr)
+        return;
+
+    // Call SID_INSERTPAGE with the right arguments.  This is because
+    // the popup menu can not call this slot with arguments directly.
+    SfxRequest aRequest (CreateRequest(SID_INSERTPAGE, aLayout));
+    if (aRequest.GetArgs() != nullptr)
+    {
+        pDispatcher->Execute(
+            SID_INSERTPAGE,
+            SfxCallMode::ASYNCHRON | SfxCallMode::RECORD,
+            *aRequest.GetArgs());
+    }
+    UpdateSelection();
+}
+
+void LayoutMenu::InvalidateContent()
+{
+    // Throw away the current set and fill the menu anew according to the
+    // current settings (this includes the support for vertical writing.)
+    Fill();
+
+    if (mxSidebar.is())
+        mxSidebar->requestLayout();
+
+    // set selection inside the control during Impress start up
+    UpdateSelection();
+}
+
+int LayoutValueSet::CalculateRowCount (const Size&, int nColumnCount)
+{
+    int nRowCount = 0;
+
+    if (GetItemCount() > 0 && nColumnCount > 0)
+    {
+        nRowCount = (GetItemCount() + nColumnCount - 1) / nColumnCount;
+        if (nRowCount < 1)
+            nRowCount = 1;
+    }
+
+    return nRowCount;
+}
+
+IMPL_LINK_NOARG(LayoutMenu, ClickHandler, ValueSet*, void)
+{
+    AssignLayoutToSelectedSlides( GetSelectedAutoLayout() );
+}
+
+/** The specified layout is assigned to the current page of the view shell
+    in the center pane.
+*/
+void LayoutMenu::AssignLayoutToSelectedSlides (AutoLayout aLayout)
+{
+    using namespace ::sd::slidesorter;
+    using namespace ::sd::slidesorter::controller;
+
+    do
+    {
+        // The view shell in the center pane has to be present.
+        ViewShell* pMainViewShell = mrBase.GetMainViewShell().get();
+        if (pMainViewShell == nullptr)
+            break;
+
+        // Determine if the current view is in an invalid master page mode.
+        // The handout view is always in master page mode and therefore not
+        // invalid.
+        bool bMasterPageMode (false);
+        switch (pMainViewShell->GetShellType())
+        {
+            case ViewShell::ST_NOTES:
+            case ViewShell::ST_IMPRESS:
+            {
+                DrawViewShell* pDrawViewShell = static_cast<DrawViewShell*>(pMainViewShell);
+                if (pDrawViewShell->GetEditMode() == EditMode::MasterPage)
+                    bMasterPageMode = true;
+                break;
+            }
+            default:
+                break;
+        }
+        if (bMasterPageMode)
+            break;
+
+        // Get a list of all selected slides and call the SID_MODIFYPAGE
+        // slot for all of them.
+        ::sd::slidesorter::SharedPageSelection pPageSelection;
+
+        // Get a list of selected pages.
+        // First we try to obtain this list from a slide sorter.  This is
+        // possible only some of the view shells in the center pane.  When
+        // no valid slide sorter is available then ask the main view shell
+        // for its current page.
+        SlideSorterViewShell* pSlideSorter = nullptr;
+        switch (pMainViewShell->GetShellType())
+        {
+            case ViewShell::ST_IMPRESS:
+            case ViewShell::ST_NOTES:
+            case ViewShell::ST_SLIDE_SORTER:
+                pSlideSorter = SlideSorterViewShell::GetSlideSorter(mrBase);
+                break;
+            default:
+                break;
+        }
+        if (pSlideSorter != nullptr)
+        {
+            // There is a slide sorter visible so get the list of selected pages from it.
+            pPageSelection = pSlideSorter->GetPageSelection();
+        }
+
+        if( (pSlideSorter == nullptr) || !pPageSelection || pPageSelection->empty() )
+        {
+            // No valid slide sorter available.  Ask the main view shell for
+            // its current page.
+            pPageSelection = std::make_shared<::sd::slidesorter::SlideSorterViewShell::PageSelection>();
+            pPageSelection->push_back(pMainViewShell->GetActualPage());
+        }
+
+        if (pPageSelection->empty())
+            break;
+
+        for (const auto& rpPage : *pPageSelection)
+        {
+            if (rpPage == nullptr)
+                continue;
+
+            // Call the SID_ASSIGN_LAYOUT slot with all the necessary parameters.
+            SfxRequest aRequest (mrBase.GetViewFrame(), SID_ASSIGN_LAYOUT);
+            aRequest.AppendItem(SfxUInt32Item (ID_VAL_WHATPAGE, (rpPage->GetPageNum()-1)/2));
+            aRequest.AppendItem(SfxUInt32Item (ID_VAL_WHATLAYOUT, aLayout));
+            pMainViewShell->ExecuteSlot (aRequest, false);
+        }
+    }
+    while(false);
+}
+
+SfxRequest LayoutMenu::CreateRequest (
+    sal_uInt16 nSlotId,
+    AutoLayout aLayout)
+{
+    SfxRequest aRequest (mrBase.GetViewFrame(), nSlotId);
+
+    do
+    {
+        SdrLayerAdmin& rLayerAdmin (mrBase.GetDocument()->GetLayerAdmin());
+        SdrLayerID aBackground (rLayerAdmin.GetLayerID(sUNO_LayerName_background));
+        SdrLayerID aBackgroundObject (rLayerAdmin.GetLayerID(sUNO_LayerName_background_objects));
+        ViewShell* pViewShell = mrBase.GetMainViewShell().get();
+        if (pViewShell == nullptr)
+            break;
+        SdPage* pPage = pViewShell->GetActualPage();
+        if (pPage == nullptr)
+            break;
+
+        SdrLayerIDSet aVisibleLayers (pPage->TRG_GetMasterPageVisibleLayers());
+
+        aRequest.AppendItem(
+            SfxStringItem (ID_VAL_PAGENAME, OUString()));//pPage->GetName()));
+        aRequest.AppendItem(SfxUInt32Item (ID_VAL_WHATLAYOUT, aLayout));
+        aRequest.AppendItem(
+            SfxBoolItem(ID_VAL_ISPAGEBACK, aVisibleLayers.IsSet(aBackground)));
+        aRequest.AppendItem(
+            SfxBoolItem(
+                ID_VAL_ISPAGEOBJ,
+                aVisibleLayers.IsSet(aBackgroundObject)));
+    }
+    while (false);
+
+    return aRequest;
+}
+
+void LayoutMenu::Fill()
+{
+    bool bVertical = SvtCJKOptions::IsVerticalTextEnabled();
+    SdDrawDocument* pDocument = mrBase.GetDocument();
+    bool bRightToLeft = (pDocument!=nullptr
+        && pDocument->GetDefaultWritingMode() == WritingMode_RL_TB);
+
+    // Get URL of the view in the center pane.
+    OUString sCenterPaneViewName;
+    try
+    {
+        Reference<XControllerManager> xControllerManager (
+            Reference<XWeak>(&mrBase.GetDrawController()), UNO_QUERY_THROW);
+        Reference<XResourceId> xPaneId (ResourceId::create(
+            ::comphelper::getProcessComponentContext(),
+            FrameworkHelper::msCenterPaneURL));
+        Reference<XView> xView (FrameworkHelper::Instance(mrBase)->GetView(xPaneId));
+        if (xView.is())
+            sCenterPaneViewName = xView->getResourceId()->getResourceURL();
+    }
+    catch (RuntimeException&)
+    {}
+
+    const snew_slide_value_info* pInfo = nullptr;
+    if (sCenterPaneViewName == framework::FrameworkHelper::msNotesViewURL)
+    {
+        pInfo = notes;
+    }
+    else if (sCenterPaneViewName == framework::FrameworkHelper::msHandoutViewURL)
+    {
+        pInfo = handout;
+    }
+    else if (sCenterPaneViewName == framework::FrameworkHelper::msImpressViewURL
+        || sCenterPaneViewName == framework::FrameworkHelper::msSlideSorterURL)
+    {
+        pInfo = standard;
+    }
+    else
+    {
+        pInfo = nullptr;
+    }
+
+    Clear();
+    for (sal_uInt16 i=1; pInfo!=nullptr && pInfo->mpStrResId; i++, pInfo++)
+    {
+        if ((WritingMode_TB_RL != pInfo->meWritingMode) || bVertical)
+        {
+            Image aImg("private:graphicrepository/" + static_cast<const OUString &>(pInfo->msBmpResId));
+
+            if (bRightToLeft && (WritingMode_TB_RL != pInfo->meWritingMode))
+            { // FIXME: avoid interpolating RTL layouts.
+                BitmapEx aRTL = aImg.GetBitmapEx();
+                aRTL.Mirror(BmpMirrorFlags::Horizontal);
+                aImg = Image(aRTL);
+            }
+
+            mxLayoutValueSet->InsertItem(i, aImg, SdResId(pInfo->mpStrResId));
+            mxLayoutValueSet->SetItemData (i, new AutoLayout(pInfo->maAutoLayout));
+        }
+    }
+}
+
+void LayoutMenu::Clear()
+{
+    for (size_t nId=1; nId<=mxLayoutValueSet->GetItemCount(); nId++)
+        delete static_cast<AutoLayout*>(mxLayoutValueSet->GetItemData(nId));
+    mxLayoutValueSet->Clear();
+}
+
+void LayoutMenu::ShowContextMenu(const Point* pPos)
+{
+    if (SD_MOD()->GetWaterCan())
+        return;
+
+    // Determine the position where to show the menu.
+    Point aMenuPosition;
+    if (pPos)
+    {
+        auto nItemId = mxLayoutValueSet->GetItemId(*pPos);
+        if (nItemId <= 0)
+            return;
+        mxLayoutValueSet->SelectItem(nItemId);
+        aMenuPosition = *pPos;
+    }
+    else
+    {
+        if (mxLayoutValueSet->GetSelectedItemId() == sal_uInt16(-1))
+            return;
+        ::tools::Rectangle aBBox(mxLayoutValueSet->GetItemRect(mxLayoutValueSet->GetSelectedItemId()));
+        aMenuPosition = aBBox.Center();
+    }
+
+    // Setup the menu.
+    ::tools::Rectangle aRect(aMenuPosition, Size(1, 1));
+    weld::Widget* pPopupParent = mxLayoutValueSet->GetDrawingArea();
+    std::unique_ptr<weld::Builder> xBuilder(Application::CreateBuilder(pPopupParent, "modules/simpress/ui/layoutmenu.ui"));
+    std::unique_ptr<weld::Menu> xMenu(xBuilder->weld_menu("menu"));
+
+    // Disable the SID_INSERTPAGE_LAYOUT_MENU item when
+    // the document is read-only.
+    const SfxPoolItem* pItem = nullptr;
+    const SfxItemState aState (
+        mrBase.GetViewFrame()->GetDispatcher()->QueryState(SID_INSERTPAGE, pItem));
+    if (aState == SfxItemState::DISABLED)
+        xMenu->set_sensitive("insert", false);
+
+    // Show the menu.
+    OnMenuItemSelected(xMenu->popup_at_rect(pPopupParent, aRect));
+}
+
+IMPL_LINK_NOARG(LayoutMenu, StateChangeHandler, const OUString&, void)
+{
+    InvalidateContent();
+}
+
+void LayoutMenu::OnMenuItemSelected(std::string_view ident)
+{
+    if (ident.empty())
+        return;
+
+    if (ident == "apply")
+    {
+        AssignLayoutToSelectedSlides(GetSelectedAutoLayout());
+    }
+    else if (ident == "insert")
+    {
+        // Add arguments to this slot and forward it to the main view
+        // shell.
+        InsertPageWithLayout(GetSelectedAutoLayout());
+    }
+}
+
+// Selects an appropriate layout of the slide inside control.
+//
+// Method may be called several times with the same item-id to be selected -
+// only once the actually state of the control will be changed.
+//
+void LayoutMenu::UpdateSelection()
+{
+    bool bItemSelected = false;
+
+    do
+    {
+        // Get current page of main view.
+        ViewShell* pViewShell = mrBase.GetMainViewShell().get();
+        if (pViewShell == nullptr)
+            break;
+
+        SdPage* pCurrentPage = pViewShell->getCurrentPage();
+        if (pCurrentPage == nullptr)
+            break;
+
+        // Get layout of current page.
+        AutoLayout aLayout (pCurrentPage->GetAutoLayout());
+        if (aLayout<AUTOLAYOUT_START || aLayout>AUTOLAYOUT_END)
+            break;
+
+        // Find the entry of the menu for to the layout.
+        const sal_uInt16 nItemCount = mxLayoutValueSet->GetItemCount();
+        for (sal_uInt16 nId=1; nId<=nItemCount; nId++)
+        {
+            if (*static_cast<AutoLayout*>(mxLayoutValueSet->GetItemData(nId)) == aLayout)
+            {
+                // do not set selection twice to the same item
+                if (mxLayoutValueSet->GetSelectedItemId() != nId)
+                {
+                    mxLayoutValueSet->SetNoSelection();
+                    mxLayoutValueSet->SelectItem(nId);
+                }
+
+                bItemSelected = true; // no need to call SetNoSelection()
+                break;
+            }
+        }
+    }
+    while (false);
+
+    if (!bItemSelected)
+        mxLayoutValueSet->SetNoSelection();
+}
+
+IMPL_LINK(LayoutMenu, EventMultiplexerListener, ::sd::tools::EventMultiplexerEvent&, rEvent, void)
+{
+    switch (rEvent.meEventId)
+    {
+        // tdf#89890 During changes of the Layout of the slide when focus is not set inside main area
+        // we do not receive notification EventMultiplexerEventId::CurrentPageChanged, but we receive the following 3 notification types.
+        // => let's make UpdateSelection() also when some shape is changed (during Layout changes)
+        case EventMultiplexerEventId::ShapeChanged:
+        case EventMultiplexerEventId::ShapeInserted:
+        case EventMultiplexerEventId::ShapeRemoved:
+            UpdateSelection();
+            break;
+
+        case EventMultiplexerEventId::CurrentPageChanged:
+        case EventMultiplexerEventId::SlideSortedSelection:
+            UpdateSelection();
+            break;
+
+        case EventMultiplexerEventId::MainViewAdded:
+            mbIsMainViewChangePending = true;
+            break;
+
+        case EventMultiplexerEventId::MainViewRemoved:
+            mxLayoutValueSet->Invalidate(); // redraw without focus
+            break;
+
+        case EventMultiplexerEventId::ConfigurationUpdated:
+            if (mbIsMainViewChangePending)
+            {
+                mbIsMainViewChangePending = false;
+                InvalidateContent();
+            }
+            break;
+
+        default:
+            break;
+    }
+}
+
+void LayoutMenu::DataChanged(const DataChangedEvent& rEvent)
+{
+    PanelLayout::DataChanged(rEvent);
+    Fill();
+    mxLayoutValueSet->StyleUpdated();
+    mxLayoutValueSet->SetColor(sfx2::sidebar::Theme::GetColor(sfx2::sidebar::Theme::Color_PanelBackground));
+}
+
+} // end of namespace ::sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/LayoutMenu.hxx b/sd/source/ui/sidebar/LayoutMenu.hxx
new file mode 100644
index 000000000..4cc916858
--- /dev/null
+++ b/sd/source/ui/sidebar/LayoutMenu.hxx
@@ -0,0 +1,157 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sfx2/sidebar/ILayoutableWindow.hxx>
+#include <sfx2/sidebar/PanelLayout.hxx>
+
+#include <svtools/valueset.hxx>
+#include <sfx2/request.hxx>
+#include <xmloff/autolayout.hxx>
+
+namespace com::sun::star::frame
+{
+class XStatusListener;
+}
+namespace com::sun::star::ui
+{
+class XSidebar;
+}
+
+namespace sd
+{
+class DrawDocShell;
+class ViewShellBase;
+}
+
+namespace sd::tools
+{
+class EventMultiplexerEvent;
+}
+
+namespace sd::sidebar
+{
+class LayoutValueSet;
+
+class LayoutMenu : public PanelLayout, public sfx2::sidebar::ILayoutableWindow
+{
+public:
+    /** Create a new layout menu.  Depending on the given flag it
+        displays its own scroll bar or lets a surrounding window
+        handle that.
+        @param i_pParent
+            the parent node in the control tree
+        @param i_rPanelViewShell
+            the view shell of the task pane.
+    */
+    LayoutMenu(weld::Widget* pParent, ViewShellBase& rViewShellBase,
+               const css::uno::Reference<css::ui::XSidebar>& rxSidebar);
+    virtual ~LayoutMenu() override;
+
+    void Dispose();
+
+    /** Return a numerical value representing the currently selected
+        layout.
+    */
+    AutoLayout GetSelectedAutoLayout() const;
+
+    // From ILayoutableWindow
+    virtual css::ui::LayoutSize GetHeightForWidth(const sal_Int32 nWidth) override;
+
+    /** Call this method when the set of displayed layouts is not up-to-date
+        anymore.  It will re-assemble this set according to the current
+        settings.
+    */
+    void InvalidateContent();
+
+    /** The context menu is requested over this ShowContextMenu() method.
+    */
+    void ShowContextMenu(const Point* pPos);
+
+    /** Call Fill() when switching to or from high contrast mode so that the
+        correct set of icons is displayed.
+    */
+    virtual void DataChanged(const DataChangedEvent& rEvent) override;
+
+private:
+    ViewShellBase& mrBase;
+
+    std::unique_ptr<LayoutValueSet> mxLayoutValueSet;
+    std::unique_ptr<weld::CustomWeld> mxLayoutValueSetWin;
+
+    /** If we are asked for the preferred window size, then use this
+        many columns for the calculation.
+    */
+    css::uno::Reference<css::frame::XStatusListener> mxListener;
+    bool mbIsMainViewChangePending;
+    css::uno::Reference<css::ui::XSidebar> mxSidebar;
+    bool mbIsDisposed;
+
+    /** Fill the value set with the layouts that are applicable to the
+        current main view shell.
+    */
+    void Fill();
+
+    /** Remove all items from the value set.
+    */
+    void Clear();
+
+    /** Assign the given layout to all selected slides of a slide sorter.
+        If no slide sorter is active then this call is ignored.  The slide
+        sorter in the center pane is preferred if the choice exists.
+    */
+    void AssignLayoutToSelectedSlides(AutoLayout aLayout);
+
+    /** Insert a new page with the given layout.  The page is inserted via
+        the main view shell, i.e. its SID_INSERTPAGE slot is called. If it
+        does not support this slot then inserting a new page does not take
+        place.  The new page is inserted after the currently active one (the
+        one returned by ViewShell::GetActualPage().)
+    */
+    void InsertPageWithLayout(AutoLayout aLayout);
+
+    /** Create a request structure that can be used with the SID_INSERTPAGE
+        and SID_MODIFYPAGE slots.  The parameters are set so that the given
+        layout is assigned to the current page of the main view shell.
+        @param nSlotId
+            Supported slots are SID_INSERTPAGE and SID_MODIFYPAGE.
+        @param aLayout
+            Layout of the page to insert or to assign.
+    */
+    SfxRequest CreateRequest(sal_uInt16 nSlotId, AutoLayout aLayout);
+
+    /** Select the layout that is used by the current page.
+    */
+    void UpdateSelection();
+
+    // internal ctor
+    void implConstruct(DrawDocShell& rDocumentShell);
+
+    /** When clicked then set the current page of the view in the center pane.
+    */
+    DECL_LINK(ClickHandler, ValueSet*, void);
+    DECL_LINK(StateChangeHandler, const OUString&, void);
+    DECL_LINK(EventMultiplexerListener, ::sd::tools::EventMultiplexerEvent&, void);
+    void OnMenuItemSelected(std::string_view ident);
+};
+
+} // end of namespace ::sd::toolpanel
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageContainer.cxx b/sd/source/ui/sidebar/MasterPageContainer.cxx
new file mode 100644
index 000000000..20d852807
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageContainer.cxx
@@ -0,0 +1,958 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "MasterPageContainer.hxx"
+
+#include "MasterPageContainerProviders.hxx"
+#include "MasterPageDescriptor.hxx"
+#include "MasterPageContainerFiller.hxx"
+#include "MasterPageContainerQueue.hxx"
+#include <PreviewRenderer.hxx>
+#include <tools/SdGlobalResourceContainer.hxx>
+#include <strings.hrc>
+#include <algorithm>
+#include <memory>
+
+#include <unomodel.hxx>
+#include <com/sun/star/lang/XMultiServiceFactory.hpp>
+#include <com/sun/star/uno/Reference.hxx>
+#include <com/sun/star/uno/Any.hxx>
+#include <com/sun/star/util/XCloseable.hpp>
+#include <com/sun/star/util/CloseVetoException.hpp>
+#include <comphelper/processfactory.hxx>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include <sdresid.hxx>
+#include <tools/TimerBasedTaskExecution.hxx>
+#include <o3tl/safeint.hxx>
+#include <osl/mutex.hxx>
+#include <osl/getglobalmutex.hxx>
+#include <xmloff/autolayout.hxx>
+#include <tools/debug.hxx>
+#include <osl/diagnose.h>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+
+namespace {
+
+typedef ::std::vector<sd::sidebar::SharedMasterPageDescriptor> MasterPageContainerType;
+
+} // end of anonymous namespace
+
+namespace sd::sidebar {
+
+/** Inner implementation class of the MasterPageContainer.
+*/
+class MasterPageContainer::Implementation
+    : public SdGlobalResource,
+      public MasterPageContainerFiller::ContainerAdapter,
+      public MasterPageContainerQueue::ContainerAdapter
+{
+public:
+    mutable ::osl::Mutex maMutex;
+
+    static std::weak_ptr<Implementation> mpInstance;
+    MasterPageContainerType maContainer;
+
+    static std::shared_ptr<Implementation> Instance();
+
+    void LateInit();
+    void AddChangeListener (const Link<MasterPageContainerChangeEvent&,void>& rLink);
+    void RemoveChangeListener (const Link<MasterPageContainerChangeEvent&,void>& rLink);
+    void UpdatePreviewSizePixel();
+    const Size& GetPreviewSizePixel (PreviewSize eSize) const;
+
+    bool HasToken (Token aToken) const;
+    SharedMasterPageDescriptor GetDescriptor (MasterPageContainer::Token aToken) const;
+    virtual Token PutMasterPage (const SharedMasterPageDescriptor& rDescriptor) override;
+    void InvalidatePreview (Token aToken);
+    Image GetPreviewForToken (
+        Token aToken,
+        PreviewSize ePreviewSize);
+    PreviewState GetPreviewState (Token aToken) const;
+    bool RequestPreview (Token aToken);
+
+    Reference<frame::XModel> GetModel();
+    SdDrawDocument* GetDocument();
+
+    void FireContainerChange (
+        MasterPageContainerChangeEvent::EventType eType,
+        Token aToken);
+
+    virtual bool UpdateDescriptor (
+        const SharedMasterPageDescriptor& rpDescriptor,
+        bool bForcePageObject,
+        bool bForcePreview,
+        bool bSendEvents) override;
+
+    void ReleaseDescriptor (Token aToken);
+
+    /** Called by the MasterPageContainerFiller to notify that all master
+        pages from template documents have been added.
+    */
+    virtual void FillingDone() override;
+
+private:
+    Implementation();
+    virtual ~Implementation() override;
+
+    class Deleter { public:
+        void operator() (Implementation* pObject) { delete pObject; }
+    };
+    friend class Deleter;
+
+    enum class InitializationState { NotInitialized, Initializing, Initialized };
+    InitializationState meInitializationState;
+
+    std::unique_ptr<MasterPageContainerQueue> mpRequestQueue;
+    css::uno::Reference<css::frame::XModel> mxModel;
+    SdDrawDocument* mpDocument;
+    PreviewRenderer maPreviewRenderer;
+    /** Remember whether the first page object has already been used to
+        determine the correct size ratio.
+    */
+    bool mbFirstPageObjectSeen;
+
+    // The widths for the previews contain two pixels for the border that is
+    // painted around the preview.
+    static const int SMALL_PREVIEW_WIDTH = 72 + 2;
+    static const int LARGE_PREVIEW_WIDTH = 2*72 + 2;
+
+    /** This substitution of page preview shows "Preparing preview" and is
+        shown as long as the actual previews are not being present.
+    */
+    Image maLargePreviewBeingCreated;
+    Image maSmallPreviewBeingCreated;
+
+    /** This substitution of page preview is shown when a preview can not be
+        created and thus is not available.
+    */
+    Image maLargePreviewNotAvailable;
+    Image maSmallPreviewNotAvailable;
+
+    ::std::vector<Link<MasterPageContainerChangeEvent&,void>> maChangeListeners;
+
+    // We have to remember the tasks for initialization and filling in case
+    // a MasterPageContainer object is destroyed before these tasks have
+    // been completed.
+    std::weak_ptr<sd::tools::TimerBasedTaskExecution> mpFillerTask;
+
+    Size maSmallPreviewSizePixel;
+    Size maLargePreviewSizePixel;
+
+    Image GetPreviewSubstitution(TranslateId pId, PreviewSize ePreviewSize);
+
+    void CleanContainer();
+};
+
+//===== MasterPageContainer ===================================================
+
+std::weak_ptr<MasterPageContainer::Implementation>
+    MasterPageContainer::Implementation::mpInstance;
+
+std::shared_ptr<MasterPageContainer::Implementation>
+    MasterPageContainer::Implementation::Instance()
+{
+    std::shared_ptr<MasterPageContainer::Implementation> pInstance;
+
+    if (Implementation::mpInstance.expired())
+    {
+        ::osl::GetGlobalMutex aMutexFunctor;
+        ::osl::MutexGuard aGuard (aMutexFunctor());
+        if (Implementation::mpInstance.expired())
+        {
+            OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
+            pInstance = std::shared_ptr<MasterPageContainer::Implementation>(
+                new MasterPageContainer::Implementation(),
+                MasterPageContainer::Implementation::Deleter());
+            SdGlobalResourceContainer::Instance().AddResource(pInstance);
+            Implementation::mpInstance = pInstance;
+        }
+        else
+            pInstance = std::shared_ptr<MasterPageContainer::Implementation>(
+                Implementation::mpInstance);
+    }
+    else
+    {
+        OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
+        pInstance = std::shared_ptr<MasterPageContainer::Implementation>(
+            Implementation::mpInstance);
+    }
+
+    DBG_ASSERT(pInstance != nullptr,
+               "MasterPageContainer::Implementation::Instance(): instance is nullptr");
+    return pInstance;
+}
+
+MasterPageContainer::MasterPageContainer()
+    : mpImpl(Implementation::Instance()),
+      mePreviewSize(SMALL)
+{
+    mpImpl->LateInit();
+}
+
+MasterPageContainer::~MasterPageContainer()
+{
+}
+
+void MasterPageContainer::AddChangeListener (const Link<MasterPageContainerChangeEvent&,void>& rLink)
+{
+    mpImpl->AddChangeListener(rLink);
+}
+
+void MasterPageContainer::RemoveChangeListener (const Link<MasterPageContainerChangeEvent&,void>& rLink)
+{
+    mpImpl->RemoveChangeListener(rLink);
+}
+
+void MasterPageContainer::SetPreviewSize (PreviewSize eSize)
+{
+    mePreviewSize = eSize;
+    mpImpl->FireContainerChange(
+        MasterPageContainerChangeEvent::EventType::SIZE_CHANGED,
+        NIL_TOKEN);
+}
+
+Size const & MasterPageContainer::GetPreviewSizePixel() const
+{
+    return mpImpl->GetPreviewSizePixel(mePreviewSize);
+}
+
+MasterPageContainer::Token MasterPageContainer::PutMasterPage (
+    const std::shared_ptr<MasterPageDescriptor>& rDescriptor)
+{
+    return mpImpl->PutMasterPage(rDescriptor);
+}
+
+void MasterPageContainer::AcquireToken (Token aToken)
+{
+    SharedMasterPageDescriptor pDescriptor = mpImpl->GetDescriptor(aToken);
+    if (pDescriptor)
+    {
+        ++pDescriptor->mnUseCount;
+    }
+}
+
+void MasterPageContainer::ReleaseToken (Token aToken)
+{
+    SharedMasterPageDescriptor pDescriptor = mpImpl->GetDescriptor(aToken);
+    if (!pDescriptor)
+        return;
+
+    OSL_ASSERT(pDescriptor->mnUseCount>0);
+    --pDescriptor->mnUseCount;
+    if (pDescriptor->mnUseCount > 0)
+        return;
+
+    switch (pDescriptor->meOrigin)
+    {
+        case DEFAULT:
+        case TEMPLATE:
+        default:
+            break;
+
+        case MASTERPAGE:
+            mpImpl->ReleaseDescriptor(aToken);
+            break;
+    }
+}
+
+int MasterPageContainer::GetTokenCount() const
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    return mpImpl->maContainer.size();
+}
+
+bool MasterPageContainer::HasToken (Token aToken) const
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    return mpImpl->HasToken(aToken);
+}
+
+MasterPageContainer::Token MasterPageContainer::GetTokenForIndex (int nIndex)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    Token aResult (NIL_TOKEN);
+    if (HasToken(nIndex))
+        aResult = mpImpl->maContainer[nIndex]->maToken;
+    return aResult;
+}
+
+MasterPageContainer::Token MasterPageContainer::GetTokenForURL (
+    const OUString& sURL)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    Token aResult (NIL_TOKEN);
+    if (!sURL.isEmpty())
+    {
+        MasterPageContainerType::iterator iEntry (
+            ::std::find_if (
+                mpImpl->maContainer.begin(),
+                mpImpl->maContainer.end(),
+                MasterPageDescriptor::URLComparator(sURL)));
+        if (iEntry != mpImpl->maContainer.end())
+            aResult = (*iEntry)->maToken;
+    }
+    return aResult;
+}
+
+MasterPageContainer::Token MasterPageContainer::GetTokenForStyleName (const OUString& sStyleName)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    Token aResult (NIL_TOKEN);
+    if (!sStyleName.isEmpty())
+    {
+        MasterPageContainerType::iterator iEntry (
+            ::std::find_if (
+                mpImpl->maContainer.begin(),
+                mpImpl->maContainer.end(),
+                MasterPageDescriptor::StyleNameComparator(sStyleName)));
+        if (iEntry != mpImpl->maContainer.end())
+            aResult = (*iEntry)->maToken;
+    }
+    return aResult;
+}
+
+MasterPageContainer::Token MasterPageContainer::GetTokenForPageObject (
+    const SdPage* pPage)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    Token aResult (NIL_TOKEN);
+    if (pPage != nullptr)
+    {
+        MasterPageContainerType::iterator iEntry (
+            ::std::find_if (
+                mpImpl->maContainer.begin(),
+                mpImpl->maContainer.end(),
+                MasterPageDescriptor::PageObjectComparator(pPage)));
+        if (iEntry != mpImpl->maContainer.end())
+            aResult = (*iEntry)->maToken;
+    }
+    return aResult;
+}
+
+OUString MasterPageContainer::GetURLForToken (
+    MasterPageContainer::Token aToken)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    SharedMasterPageDescriptor pDescriptor = mpImpl->GetDescriptor(aToken);
+    if (pDescriptor)
+        return pDescriptor->msURL;
+    else
+        return OUString();
+}
+
+OUString MasterPageContainer::GetPageNameForToken (
+    MasterPageContainer::Token aToken)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    SharedMasterPageDescriptor pDescriptor = mpImpl->GetDescriptor(aToken);
+    if (pDescriptor)
+        return pDescriptor->msPageName;
+    else
+        return OUString();
+}
+
+OUString MasterPageContainer::GetStyleNameForToken (
+    MasterPageContainer::Token aToken)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    SharedMasterPageDescriptor pDescriptor = mpImpl->GetDescriptor(aToken);
+    if (pDescriptor)
+        return pDescriptor->msStyleName;
+    else
+        return OUString();
+}
+
+SdPage* MasterPageContainer::GetPageObjectForToken (
+    MasterPageContainer::Token aToken,
+    bool bLoad)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    SdPage* pPageObject = nullptr;
+    SharedMasterPageDescriptor pDescriptor = mpImpl->GetDescriptor(aToken);
+    if (pDescriptor)
+    {
+        pPageObject = pDescriptor->mpMasterPage;
+        if (pPageObject == nullptr)
+        {
+            // The page object is not (yet) present.  Call
+            // UpdateDescriptor() to trigger the PageObjectProvider() to
+            // provide it.
+            if (bLoad)
+                mpImpl->GetModel();
+            if (mpImpl->UpdateDescriptor(pDescriptor,bLoad,false, true))
+                pPageObject = pDescriptor->mpMasterPage;
+        }
+    }
+    return pPageObject;
+}
+
+MasterPageContainer::Origin MasterPageContainer::GetOriginForToken (Token aToken)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    SharedMasterPageDescriptor pDescriptor = mpImpl->GetDescriptor(aToken);
+    if (pDescriptor)
+        return pDescriptor->meOrigin;
+    else
+        return UNKNOWN;
+}
+
+sal_Int32 MasterPageContainer::GetTemplateIndexForToken (Token aToken)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    SharedMasterPageDescriptor pDescriptor = mpImpl->GetDescriptor(aToken);
+    if (pDescriptor)
+        return pDescriptor->mnTemplateIndex;
+    else
+        return -1;
+}
+
+std::shared_ptr<MasterPageDescriptor> MasterPageContainer::GetDescriptorForToken (
+    MasterPageContainer::Token aToken)
+{
+    const ::osl::MutexGuard aGuard (mpImpl->maMutex);
+
+    return mpImpl->GetDescriptor(aToken);
+}
+
+void MasterPageContainer::InvalidatePreview (MasterPageContainer::Token aToken)
+{
+    mpImpl->InvalidatePreview(aToken);
+}
+
+Image MasterPageContainer::GetPreviewForToken (MasterPageContainer::Token aToken)
+{
+    return mpImpl->GetPreviewForToken(aToken,mePreviewSize);
+}
+
+MasterPageContainer::PreviewState MasterPageContainer::GetPreviewState (Token aToken)
+{
+    return mpImpl->GetPreviewState(aToken);
+}
+
+bool MasterPageContainer::RequestPreview (Token aToken)
+{
+    return mpImpl->RequestPreview(aToken);
+}
+
+//==== Implementation ================================================
+
+MasterPageContainer::Implementation::Implementation()
+    : meInitializationState(InitializationState::NotInitialized),
+      mpDocument(nullptr),
+      mbFirstPageObjectSeen(false)
+{
+    UpdatePreviewSizePixel();
+}
+
+MasterPageContainer::Implementation::~Implementation()
+{
+    // When the initializer or filler tasks are still running then we have
+    // to stop them now in order to prevent them from calling us back.
+    tools::TimerBasedTaskExecution::ReleaseTask(mpFillerTask);
+
+    mpRequestQueue.reset();
+
+    uno::Reference<util::XCloseable> xCloseable (mxModel, uno::UNO_QUERY);
+    if (xCloseable.is())
+    {
+        try
+        {
+            xCloseable->close(true);
+        }
+        catch (const css::util::CloseVetoException&)
+        {
+        }
+    }
+    mxModel = nullptr;
+}
+
+void MasterPageContainer::Implementation::LateInit()
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    if (meInitializationState != InitializationState::NotInitialized)
+        return;
+
+    meInitializationState = InitializationState::Initializing;
+
+    OSL_ASSERT(Instance().get()==this);
+    mpRequestQueue.reset(MasterPageContainerQueue::Create(
+        std::shared_ptr<MasterPageContainerQueue::ContainerAdapter>(Instance())));
+
+    mpFillerTask = ::sd::tools::TimerBasedTaskExecution::Create(
+        std::make_shared<MasterPageContainerFiller>(*this),
+        5,
+        50);
+
+    meInitializationState = InitializationState::Initialized;
+}
+
+void MasterPageContainer::Implementation::AddChangeListener (const Link<MasterPageContainerChangeEvent&,void>& rLink)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    ::std::vector<Link<MasterPageContainerChangeEvent&,void>>::iterator iListener (
+        ::std::find(maChangeListeners.begin(),maChangeListeners.end(),rLink));
+    if (iListener == maChangeListeners.end())
+        maChangeListeners.push_back(rLink);
+
+}
+
+void MasterPageContainer::Implementation::RemoveChangeListener (const Link<MasterPageContainerChangeEvent&,void>& rLink)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    ::std::vector<Link<MasterPageContainerChangeEvent&,void>>::iterator iListener (
+        ::std::find(maChangeListeners.begin(),maChangeListeners.end(),rLink));
+    if (iListener != maChangeListeners.end())
+        maChangeListeners.erase(iListener);
+}
+
+void MasterPageContainer::Implementation::UpdatePreviewSizePixel()
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    // The default aspect ratio is 4:3
+    int nWidth (4);
+    int nHeight (3);
+
+    // Search for the first entry with an existing master page.
+    auto iDescriptor = std::find_if(maContainer.begin(), maContainer.end(),
+        [](const SharedMasterPageDescriptor& rxDescriptor) {
+            return rxDescriptor != nullptr && rxDescriptor->mpMasterPage != nullptr;
+        });
+    if (iDescriptor != maContainer.end())
+    {
+        Size aPageSize ((*iDescriptor)->mpMasterPage->GetSize());
+        OSL_ASSERT(!aPageSize.IsEmpty());
+        if (aPageSize.Width() > 0)
+            nWidth = aPageSize.Width();
+        if (aPageSize.Height() > 0)
+            nHeight = aPageSize.Height();
+        mbFirstPageObjectSeen = true;
+    }
+
+    maSmallPreviewSizePixel.setWidth( SMALL_PREVIEW_WIDTH );
+    maLargePreviewSizePixel.setWidth( LARGE_PREVIEW_WIDTH );
+
+    int nNewSmallHeight ((maSmallPreviewSizePixel.Width()-2) * nHeight / nWidth + 2);
+    int nNewLargeHeight ((maLargePreviewSizePixel.Width()-2) * nHeight / nWidth + 2);
+
+    if (nNewSmallHeight!=maSmallPreviewSizePixel.Height()
+        || nNewLargeHeight!=maLargePreviewSizePixel.Height())
+    {
+        maSmallPreviewSizePixel.setHeight( nNewSmallHeight );
+        maLargePreviewSizePixel.setHeight( nNewLargeHeight );
+        FireContainerChange(
+            MasterPageContainerChangeEvent::EventType::SIZE_CHANGED,
+            NIL_TOKEN);
+    }
+}
+
+const Size& MasterPageContainer::Implementation::GetPreviewSizePixel (PreviewSize eSize) const
+{
+    if (eSize == SMALL)
+        return maSmallPreviewSizePixel;
+    else
+        return maLargePreviewSizePixel;
+}
+
+MasterPageContainer::Token MasterPageContainer::Implementation::PutMasterPage (
+    const SharedMasterPageDescriptor& rpDescriptor)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    Token aResult (NIL_TOKEN);
+
+    // Get page object and preview when that is inexpensive.
+    UpdateDescriptor(rpDescriptor,false,false, false);
+
+    // Look up the new MasterPageDescriptor and either insert it or update
+    // an already existing one.
+    MasterPageContainerType::iterator aEntry (
+        ::std::find_if (
+            maContainer.begin(),
+            maContainer.end(),
+            MasterPageDescriptor::AllComparator(rpDescriptor)));
+    if (aEntry == maContainer.end())
+    {
+        // Insert a new MasterPageDescriptor.
+        bool bIgnore(rpDescriptor->mpPageObjectProvider == nullptr
+                     && rpDescriptor->msURL.isEmpty());
+
+        if ( ! bIgnore)
+        {
+            CleanContainer();
+
+            aResult = maContainer.size();
+            rpDescriptor->SetToken(aResult);
+
+            // Templates are precious, i.e. we lock them so that they will
+            // not be destroyed when (temporarily) no one references them.
+            // They will only be deleted when the container is destroyed.
+            switch (rpDescriptor->meOrigin)
+            {
+                case TEMPLATE:
+                case DEFAULT:
+                    ++rpDescriptor->mnUseCount;
+                    break;
+
+                default:
+                    break;
+            }
+
+            maContainer.push_back(rpDescriptor);
+            aEntry = maContainer.end()-1;
+
+            FireContainerChange(MasterPageContainerChangeEvent::EventType::CHILD_ADDED,aResult);
+        }
+    }
+    else
+    {
+        // Update an existing MasterPageDescriptor.
+        aResult = (*aEntry)->maToken;
+        std::unique_ptr<std::vector<MasterPageContainerChangeEvent::EventType> > pEventTypes(
+            (*aEntry)->Update(*rpDescriptor));
+        if (pEventTypes != nullptr && !pEventTypes->empty())
+        {
+            // One or more aspects of the descriptor have changed.  Send
+            // appropriate events to the listeners.
+            UpdateDescriptor(*aEntry,false,false, true);
+
+            for (const auto& rEventType : *pEventTypes)
+            {
+                FireContainerChange(rEventType, (*aEntry)->maToken);
+            }
+        }
+    }
+
+    return aResult;
+}
+
+bool MasterPageContainer::Implementation::HasToken (Token aToken) const
+{
+    return aToken>=0
+        && o3tl::make_unsigned(aToken)<maContainer.size()
+        && maContainer[aToken];
+}
+
+SharedMasterPageDescriptor MasterPageContainer::Implementation::GetDescriptor (Token aToken) const
+{
+    if (aToken>=0 && o3tl::make_unsigned(aToken)<maContainer.size())
+        return maContainer[aToken];
+    else
+        return SharedMasterPageDescriptor();
+}
+
+void MasterPageContainer::Implementation::InvalidatePreview (Token aToken)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    SharedMasterPageDescriptor pDescriptor (GetDescriptor(aToken));
+    if (pDescriptor)
+    {
+        pDescriptor->maSmallPreview = Image();
+        pDescriptor->maLargePreview = Image();
+        RequestPreview(aToken);
+    }
+}
+
+Image MasterPageContainer::Implementation::GetPreviewForToken (
+    MasterPageContainer::Token aToken,
+    PreviewSize ePreviewSize)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    Image aPreview;
+    PreviewState ePreviewState (GetPreviewState(aToken));
+
+    SharedMasterPageDescriptor pDescriptor = GetDescriptor(aToken);
+
+    // When the preview is missing but inexpensively creatable then do that
+    // now.
+    if (pDescriptor)
+    {
+        if (ePreviewState == PS_CREATABLE)
+            if (UpdateDescriptor(pDescriptor, false,false, true))
+                if (pDescriptor->maLargePreview.GetSizePixel().Width() != 0)
+                    ePreviewState = PS_AVAILABLE;
+
+        switch (ePreviewState)
+        {
+            case PS_AVAILABLE:
+                aPreview = pDescriptor->GetPreview(ePreviewSize);
+                break;
+
+            case PS_PREPARING:
+                aPreview = GetPreviewSubstitution(
+                    STR_TASKPANEL_PREPARING_PREVIEW_SUBSTITUTION,
+                    ePreviewSize);
+                break;
+
+            case PS_CREATABLE:
+                aPreview = GetPreviewSubstitution(
+                    STR_TASKPANEL_PREPARING_PREVIEW_SUBSTITUTION,
+                    ePreviewSize);
+                break;
+
+            case PS_NOT_AVAILABLE:
+                aPreview = GetPreviewSubstitution(
+                    STR_TASKPANEL_NOT_AVAILABLE_SUBSTITUTION,
+                    ePreviewSize);
+                if (ePreviewSize == SMALL)
+                    pDescriptor->maSmallPreview = aPreview;
+                else
+                    pDescriptor->maLargePreview = aPreview;
+                break;
+        }
+    }
+
+    return aPreview;
+}
+
+MasterPageContainer::PreviewState MasterPageContainer::Implementation::GetPreviewState (
+    Token aToken) const
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    PreviewState eState (PS_NOT_AVAILABLE);
+
+    SharedMasterPageDescriptor pDescriptor = GetDescriptor(aToken);
+    if (pDescriptor)
+    {
+        if (pDescriptor->maLargePreview.GetSizePixel().Width() != 0)
+            eState = PS_AVAILABLE;
+        else if (pDescriptor->mpPreviewProvider != nullptr)
+        {
+            // The preview does not exist but can be created.  When that is
+            // not expensive then do it at once.
+            if (mpRequestQueue->HasRequest(aToken))
+                eState = PS_PREPARING;
+            else
+                eState = PS_CREATABLE;
+        }
+        else
+            eState = PS_NOT_AVAILABLE;
+    }
+
+    return eState;
+}
+
+bool MasterPageContainer::Implementation::RequestPreview (Token aToken)
+{
+    SharedMasterPageDescriptor pDescriptor = GetDescriptor(aToken);
+    if (pDescriptor)
+        return mpRequestQueue->RequestPreview(pDescriptor);
+    else
+        return false;
+}
+
+Reference<frame::XModel> MasterPageContainer::Implementation::GetModel()
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    if ( ! mxModel.is())
+    {
+        // Create a new model.
+        mxModel.set(
+            ::comphelper::getProcessServiceFactory()->createInstance(
+                "com.sun.star.presentation.PresentationDocument"),
+            uno::UNO_QUERY);
+
+        // Initialize the model.
+        uno::Reference<frame::XLoadable> xLoadable (mxModel,uno::UNO_QUERY);
+        if (xLoadable.is())
+            xLoadable->initNew();
+
+        // Use its tunnel to get a pointer to its core implementation.
+        uno::Reference<lang::XUnoTunnel> xUnoTunnel (mxModel, uno::UNO_QUERY);
+        if (auto pSdXImpressDocument = comphelper::getFromUnoTunnel<SdXImpressDocument>(xUnoTunnel))
+        {
+            mpDocument = pSdXImpressDocument->GetDoc();
+        }
+
+        // Create a default page.
+        uno::Reference<drawing::XDrawPagesSupplier> xSlideSupplier (mxModel, uno::UNO_QUERY);
+        if (xSlideSupplier.is())
+        {
+            uno::Reference<drawing::XDrawPages> xSlides =
+                xSlideSupplier->getDrawPages();
+            if (xSlides.is())
+            {
+                uno::Reference<drawing::XDrawPage> xNewPage (xSlides->insertNewByIndex(0));
+                uno::Reference<beans::XPropertySet> xProperties(xNewPage, uno::UNO_QUERY);
+                if (xProperties.is())
+                    xProperties->setPropertyValue(
+                        "Layout",
+                        Any(sal_Int16(AUTOLAYOUT_TITLE)));
+            }
+        }
+    }
+    return mxModel;
+}
+
+SdDrawDocument* MasterPageContainer::Implementation::GetDocument()
+{
+    GetModel();
+    return mpDocument;
+}
+
+Image MasterPageContainer::Implementation::GetPreviewSubstitution (
+    TranslateId pId,
+    PreviewSize ePreviewSize)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    Image aPreview;
+
+    if (pId == STR_TASKPANEL_PREPARING_PREVIEW_SUBSTITUTION)
+    {
+        Image& rPreview (ePreviewSize==SMALL
+            ? maSmallPreviewBeingCreated
+            : maLargePreviewBeingCreated);
+        if (rPreview.GetSizePixel().Width() == 0)
+        {
+            rPreview = maPreviewRenderer.RenderSubstitution(
+                ePreviewSize==SMALL ? maSmallPreviewSizePixel : maLargePreviewSizePixel,
+                SdResId(STR_TASKPANEL_PREPARING_PREVIEW_SUBSTITUTION));
+        }
+        aPreview = rPreview;
+    }
+    else if (pId == STR_TASKPANEL_NOT_AVAILABLE_SUBSTITUTION)
+    {
+        Image& rPreview (ePreviewSize==SMALL
+            ? maSmallPreviewNotAvailable
+            : maLargePreviewNotAvailable);
+        if (rPreview.GetSizePixel().Width() == 0)
+        {
+            rPreview = maPreviewRenderer.RenderSubstitution(
+                ePreviewSize==SMALL ? maSmallPreviewSizePixel : maLargePreviewSizePixel,
+                SdResId(STR_TASKPANEL_NOT_AVAILABLE_SUBSTITUTION));
+        }
+        aPreview = rPreview;
+    }
+
+    return aPreview;
+}
+
+void MasterPageContainer::Implementation::CleanContainer()
+{
+    // Remove the empty elements at the end of the container.  The empty
+    // elements in the middle can not be removed because that would
+    // invalidate the references still held by others.
+    int nIndex (maContainer.size()-1);
+    while (nIndex>=0 && !maContainer[nIndex])
+        --nIndex;
+    maContainer.resize(++nIndex);
+}
+
+void MasterPageContainer::Implementation::FireContainerChange (
+    MasterPageContainerChangeEvent::EventType eType,
+    Token aToken)
+{
+    ::std::vector<Link<MasterPageContainerChangeEvent&,void>> aCopy(maChangeListeners);
+    MasterPageContainerChangeEvent aEvent;
+    aEvent.meEventType = eType;
+    aEvent.maChildToken = aToken;
+    for (const auto& rListener : aCopy)
+        rListener.Call(aEvent);
+}
+
+bool MasterPageContainer::Implementation::UpdateDescriptor (
+    const SharedMasterPageDescriptor& rpDescriptor,
+    bool bForcePageObject,
+    bool bForcePreview,
+    bool bSendEvents)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    // We have to create the page object when the preview provider needs it
+    // and the caller needs the preview.
+    bForcePageObject |= (bForcePreview
+        && rpDescriptor->mpPreviewProvider->NeedsPageObject()
+        && rpDescriptor->mpMasterPage==nullptr);
+
+    // Define a cost threshold so that an update or page object or preview
+    // that is at least this cost are made at once. Updates with higher cost
+    // are scheduled for later.
+    sal_Int32 nCostThreshold (mpRequestQueue->IsEmpty() ? 5 : 0);
+
+    // Update the page object (which may be used for the preview update).
+    if (bForcePageObject)
+        GetDocument();
+    int nPageObjectModified (rpDescriptor->UpdatePageObject(
+        (bForcePageObject ? -1 : nCostThreshold),
+        mpDocument));
+    if (nPageObjectModified == 1 && bSendEvents)
+        FireContainerChange(
+            MasterPageContainerChangeEvent::EventType::DATA_CHANGED,
+            rpDescriptor->maToken);
+    if (nPageObjectModified == -1 && bSendEvents)
+        FireContainerChange(
+            MasterPageContainerChangeEvent::EventType::CHILD_REMOVED,
+            rpDescriptor->maToken);
+    if (nPageObjectModified && ! mbFirstPageObjectSeen)
+        UpdatePreviewSizePixel();
+
+    // Update the preview.
+    bool bPreviewModified (rpDescriptor->UpdatePreview(
+        (bForcePreview ? -1 : nCostThreshold),
+        maSmallPreviewSizePixel,
+        maLargePreviewSizePixel,
+        maPreviewRenderer));
+
+    if (bPreviewModified && bSendEvents)
+        FireContainerChange(
+            MasterPageContainerChangeEvent::EventType::PREVIEW_CHANGED,
+            rpDescriptor->maToken);
+
+    return nPageObjectModified || bPreviewModified;
+}
+
+void MasterPageContainer::Implementation::ReleaseDescriptor (Token aToken)
+{
+    if (aToken>=0 && o3tl::make_unsigned(aToken)<maContainer.size())
+    {
+        maContainer[aToken].reset();
+    }
+}
+
+void MasterPageContainer::Implementation::FillingDone()
+{
+    mpRequestQueue->ProcessAllRequests();
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageContainer.hxx b/sd/source/ui/sidebar/MasterPageContainer.hxx
new file mode 100644
index 000000000..9de4eb6bc
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageContainer.hxx
@@ -0,0 +1,199 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <vcl/image.hxx>
+
+#include <memory>
+
+class SdPage;
+
+namespace sd::sidebar
+{
+class MasterPageDescriptor;
+class MasterPageContainerChangeEvent;
+
+/** This container manages the master pages used by the MasterPagesSelector
+    controls.  It uses internally a singleton implementation object.
+    Therefore, all MasterPageContainer object operator on the same set of
+    master pages.  Each MasterPageContainer, however, has its own
+    PreviewSize value and thus can independently switch between large and
+    small previews.
+
+    The container maintains its own document to store master page objects.
+
+    For each master page container stores its URL, preview bitmap, page
+    name, and, if available, the page object.
+
+    Entries are accessed via a Token, which is mostly a numerical index but
+    whose values do not necessarily have to be consecutive.
+*/
+class MasterPageContainer final
+{
+public:
+    typedef int Token;
+    static const Token NIL_TOKEN = -1;
+
+    MasterPageContainer();
+    ~MasterPageContainer();
+
+    void AddChangeListener(const Link<MasterPageContainerChangeEvent&, void>& rLink);
+    void RemoveChangeListener(const Link<MasterPageContainerChangeEvent&, void>& rLink);
+
+    enum PreviewSize
+    {
+        SMALL,
+        LARGE
+    };
+    /** There are two different preview sizes, a small one and a large one.
+        Which one is used by the called container can be changed with this
+        method.
+        When the preview size is changed then all change listeners are
+        notified of this.
+    */
+    void SetPreviewSize(PreviewSize eSize);
+
+    /** Returns the preview size.
+    */
+    PreviewSize GetPreviewSize() const { return mePreviewSize; }
+
+    /** Return the preview size in pixels.
+    */
+    Size const& GetPreviewSizePixel() const;
+
+    enum PreviewState
+    {
+        PS_AVAILABLE,
+        PS_CREATABLE,
+        PS_PREPARING,
+        PS_NOT_AVAILABLE
+    };
+    PreviewState GetPreviewState(Token aToken);
+
+    /** This method is typically called for entries in the container for
+        which GetPreviewState() returns OS_CREATABLE.  The creation of the
+        preview is then scheduled to be executed asynchronously at a later
+        point in time.  When the preview is available the change listeners
+        will be notified.
+    */
+    bool RequestPreview(Token aToken);
+
+    /** Each entry of the container is either the first page of a template
+        document or is a master page of an Impress document.
+    */
+    enum Origin
+    {
+        MASTERPAGE, // Master page of a document.
+        TEMPLATE, // First page of a template file.
+        DEFAULT, // Empty master page with default style.
+        UNKNOWN
+    };
+
+    /** Put the master page identified and described by the given parameters
+        into the container.  When there already is a master page with the
+        given URL, page name, or object pointer (when that is not NULL) then
+        the existing entry is replaced/updated by the given one.  Otherwise
+        a new entry is inserted.
+    */
+    Token PutMasterPage(const std::shared_ptr<MasterPageDescriptor>& rDescriptor);
+    void AcquireToken(Token aToken);
+    void ReleaseToken(Token aToken);
+
+    /** This and the GetTokenForIndex() methods can be used to iterate over
+        all members of the container.
+    */
+    int GetTokenCount() const;
+
+    /** Determine whether the container has a member for the given token.
+    */
+    bool HasToken(Token aToken) const;
+
+    /** Return a token for an index in the range
+        0 <= index < GetTokenCount().
+    */
+    Token GetTokenForIndex(int nIndex);
+
+    Token GetTokenForURL(const OUString& sURL);
+    Token GetTokenForStyleName(const OUString& sStyleName);
+    Token GetTokenForPageObject(const SdPage* pPage);
+
+    OUString GetURLForToken(Token aToken);
+    OUString GetPageNameForToken(Token aToken);
+    OUString GetStyleNameForToken(Token aToken);
+    SdPage* GetPageObjectForToken(Token aToken, bool bLoad);
+    Origin GetOriginForToken(Token aToken);
+    sal_Int32 GetTemplateIndexForToken(Token aToken);
+    std::shared_ptr<MasterPageDescriptor> GetDescriptorForToken(Token aToken);
+
+    void InvalidatePreview(Token aToken);
+
+    /** Return a preview for the specified token.  When the preview is not
+        present then the PreviewProvider associated with the token is
+        executed only when that is not expensive.  It is the responsibility
+        of the caller to call RequestPreview() to do the same
+        (asynchronously) for expensive PreviewProviders.
+        Call GetPreviewState() to find out if that is necessary.
+        @param aToken
+            This token specifies for which master page to return the preview.
+            Tokens are returned for example by the GetTokenFor...() methods.
+        @return
+            The returned image is the requested preview or a substitution.
+    */
+    Image GetPreviewForToken(Token aToken);
+
+private:
+    class Implementation;
+    std::shared_ptr<Implementation> mpImpl;
+    PreviewSize mePreviewSize;
+};
+
+/** For some changes to the set of master pages in a MasterPageContainer or
+    to the data stored for each master page one or more events are sent to
+    registered listeners.
+    Each event has an event type and a token that tells the listener where
+    the change took place.
+*/
+class MasterPageContainerChangeEvent
+{
+public:
+    enum class EventType
+    {
+        // A master page was added to the container.
+        CHILD_ADDED,
+        // A master page was removed from the container.
+        CHILD_REMOVED,
+        // The preview of a master page has changed.
+        PREVIEW_CHANGED,
+        // The size of a preview has changed.
+        SIZE_CHANGED,
+        // Some of the data stored for a master page has changed.
+        DATA_CHANGED,
+        // The TemplateIndex of a master page has changed.
+        INDEX_CHANGED,
+    } meEventType;
+
+    // Token of the container entry whose data changed or which was added or
+    // removed.
+    MasterPageContainer::Token maChildToken;
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageContainerFiller.cxx b/sd/source/ui/sidebar/MasterPageContainerFiller.cxx
new file mode 100644
index 000000000..3568d9c71
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageContainerFiller.cxx
@@ -0,0 +1,168 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "MasterPageContainerFiller.hxx"
+
+#include "MasterPageDescriptor.hxx"
+#include "MasterPageContainerProviders.hxx"
+#include <TemplateScanner.hxx>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+
+namespace sd::sidebar {
+
+MasterPageContainerFiller::MasterPageContainerFiller (ContainerAdapter& rpAdapter)
+    : mrContainerAdapter(rpAdapter),
+      meState(INITIALIZE_TEMPLATE_SCANNER),
+      mpLastAddedEntry(nullptr),
+      mnIndex(1)
+{
+    // Add one entry for the default master page.  We use temporarily the
+    // DefaultPagePreviewProvider to prevent the rendering (and the
+    // expensive creation) of the default page.  It is replaced later on by
+    // another.
+    SharedMasterPageDescriptor pDescriptor = std::make_shared<MasterPageDescriptor>(
+        MasterPageContainer::DEFAULT,
+        0,
+        OUString(),
+        OUString(),
+        OUString(),
+        false,
+        std::make_shared<DefaultPageObjectProvider>(),
+        std::make_shared<PagePreviewProvider>());
+    mrContainerAdapter.PutMasterPage(pDescriptor);
+}
+
+MasterPageContainerFiller::~MasterPageContainerFiller()
+{
+}
+
+void MasterPageContainerFiller::RunNextStep()
+{
+    switch (meState)
+    {
+        case INITIALIZE_TEMPLATE_SCANNER:
+            mpScannerTask.reset(new TemplateScanner());
+            meState = SCAN_TEMPLATE;
+            break;
+
+        case SCAN_TEMPLATE:
+            meState = ScanTemplate();
+            break;
+
+        case ADD_TEMPLATE:
+            meState = AddTemplate();
+            break;
+
+        case DONE:
+        case ERROR:
+        default:
+            break;
+    }
+
+    // When the state has just been set to DONE or ERROR then tell the
+    // container that no more templates will be coming and stop the
+    // scanning.
+    switch (meState)
+    {
+        case DONE:
+        case ERROR:
+            if (mpScannerTask != nullptr)
+            {
+                mrContainerAdapter.FillingDone();
+                mpScannerTask.reset();
+            }
+            break;
+        default:
+            break;
+    }
+}
+
+bool MasterPageContainerFiller::HasNextStep()
+{
+    switch (meState)
+    {
+        case DONE:
+        case ERROR:
+            return false;
+
+        default:
+            return true;
+    }
+}
+
+MasterPageContainerFiller::State MasterPageContainerFiller::ScanTemplate()
+{
+    State eState (ERROR);
+
+    if (mpScannerTask != nullptr)
+    {
+        if (mpScannerTask->HasNextStep())
+        {
+            mpScannerTask->RunNextStep();
+            if (mpScannerTask->GetLastAddedEntry() != mpLastAddedEntry)
+            {
+                mpLastAddedEntry = mpScannerTask->GetLastAddedEntry();
+                if (mpLastAddedEntry != nullptr)
+                    eState = ADD_TEMPLATE;
+                else
+                    eState = SCAN_TEMPLATE;
+            }
+            else
+                eState = SCAN_TEMPLATE;
+        }
+        else
+            eState = DONE;
+    }
+
+    return eState;
+}
+
+MasterPageContainerFiller::State MasterPageContainerFiller::AddTemplate()
+{
+    if (mpLastAddedEntry != nullptr)
+    {
+        SharedMasterPageDescriptor pDescriptor = std::make_shared<MasterPageDescriptor>(
+            MasterPageContainer::TEMPLATE,
+            mnIndex,
+            mpLastAddedEntry->msPath,
+            mpLastAddedEntry->msTitle,
+            OUString(),
+            false,
+            std::make_shared<TemplatePageObjectProvider>(mpLastAddedEntry->msPath),
+            std::make_shared<TemplatePreviewProvider>(mpLastAddedEntry->msPath));
+        // For user supplied templates we use a different preview provider:
+        // The preview in the document shows not only shapes on the master
+        // page but also shapes on the foreground.  This is misleading and
+        // therefore these previews are discarded and created directly from
+        // the page objects.
+        if (pDescriptor->GetURLClassification() == MasterPageDescriptor::URLCLASS_USER)
+            pDescriptor->mpPreviewProvider = std::make_shared<PagePreviewProvider>();
+
+        mrContainerAdapter.PutMasterPage(pDescriptor);
+        ++mnIndex;
+    }
+
+    return SCAN_TEMPLATE;
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageContainerFiller.hxx b/sd/source/ui/sidebar/MasterPageContainerFiller.hxx
new file mode 100644
index 000000000..b08452ab6
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageContainerFiller.hxx
@@ -0,0 +1,92 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <memory>
+#include "MasterPageContainer.hxx"
+#include "MasterPageDescriptor.hxx"
+#include <tools/AsynchronousTask.hxx>
+
+namespace sd
+{
+class TemplateScanner;
+class TemplateEntry;
+}
+
+namespace sd::sidebar
+{
+/** Fill a MasterPageContainer with information about the available master
+    pages.  These are provided by one default page and from the existing
+    Impress templates.  This is done asynchronously.
+*/
+class MasterPageContainerFiller : public ::sd::tools::AsynchronousTask
+{
+public:
+    class ContainerAdapter
+    {
+    public:
+        virtual MasterPageContainer::Token
+        PutMasterPage(const SharedMasterPageDescriptor& rpDescriptor)
+            = 0;
+        /** This method is called when all Impress templates have been added
+            to the container via the PutMasterPage() method.
+        */
+        virtual void FillingDone() = 0;
+
+    protected:
+        ~ContainerAdapter() {}
+    };
+
+    explicit MasterPageContainerFiller(ContainerAdapter& rContainerAdapter);
+    virtual ~MasterPageContainerFiller();
+
+    /** Run the next step of the task.  After HasNextStep() returns false
+        this method should ignore further calls.
+    */
+    virtual void RunNextStep() override;
+
+    /** Return <TRUE/> when there is at least one more step to execute.
+        When the task has been executed completely then <FALSE/> is
+        returned.
+    */
+    virtual bool HasNextStep() override;
+
+private:
+    ContainerAdapter& mrContainerAdapter;
+    // Remember what the next step has to do.
+    enum State
+    {
+        INITIALIZE_TEMPLATE_SCANNER,
+        SCAN_TEMPLATE,
+        ADD_TEMPLATE,
+        ERROR,
+        DONE
+    } meState;
+    ::std::unique_ptr<TemplateScanner> mpScannerTask;
+    const TemplateEntry* mpLastAddedEntry;
+    int mnIndex;
+
+    State ScanTemplate();
+    State AddTemplate();
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageContainerProviders.cxx b/sd/source/ui/sidebar/MasterPageContainerProviders.cxx
new file mode 100644
index 000000000..785536daa
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageContainerProviders.cxx
@@ -0,0 +1,205 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "MasterPageContainerProviders.hxx"
+
+#include <DrawDocShell.hxx>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include <PreviewRenderer.hxx>
+#include <svl/eitem.hxx>
+#include <sfx2/app.hxx>
+#include <sfx2/sfxsids.hrc>
+#include <sfx2/thumbnailview.hxx>
+#include <vcl/image.hxx>
+#include <tools/diagnose_ex.h>
+#include <sal/log.hxx>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+
+namespace sd::sidebar {
+
+//===== PagePreviewProvider ===================================================
+
+PagePreviewProvider::PagePreviewProvider()
+{
+}
+
+Image PagePreviewProvider::operator () (
+    int nWidth,
+    SdPage* pPage,
+    ::sd::PreviewRenderer& rRenderer)
+{
+    Image aPreview;
+
+    if (pPage != nullptr)
+    {
+        // Use the given renderer to create a preview of the given page
+        // object.
+        aPreview = rRenderer.RenderPage(
+            pPage,
+            nWidth);
+    }
+
+    return aPreview;
+}
+
+int PagePreviewProvider::GetCostIndex()
+{
+    return 5;
+}
+
+bool PagePreviewProvider::NeedsPageObject()
+{
+    return true;
+}
+
+//===== TemplatePreviewProvider ===============================================
+
+TemplatePreviewProvider::TemplatePreviewProvider (const OUString& rsURL)
+    : msURL(rsURL)
+{
+}
+
+Image TemplatePreviewProvider::operator() (
+    int,
+    SdPage*,
+    ::sd::PreviewRenderer&)
+{
+    return Image(ThumbnailView::readThumbnail(msURL));
+}
+
+int TemplatePreviewProvider::GetCostIndex()
+{
+    return 10;
+}
+
+bool TemplatePreviewProvider::NeedsPageObject()
+{
+    return false;
+}
+
+//===== TemplatePageObjectProvider =============================================
+
+TemplatePageObjectProvider::TemplatePageObjectProvider (const OUString& rsURL)
+    : msURL(rsURL)
+{
+}
+
+SdPage* TemplatePageObjectProvider::operator() (SdDrawDocument*)
+{
+    SdPage* pPage = nullptr;
+
+    mxDocumentShell = nullptr;
+    try
+    {
+        // Load the template document and return its first page.
+        ::sd::DrawDocShell* pDocumentShell = LoadDocument (msURL);
+        if (pDocumentShell != nullptr)
+        {
+            SdDrawDocument* pDocument = pDocumentShell->GetDoc();
+            if (pDocument != nullptr)
+            {
+                pPage = pDocument->GetMasterSdPage(0, PageKind::Standard);
+                // In order to make the newly loaded master page deletable
+                // when copied into documents it is marked as no "precious".
+                // When it is modified then it is marked as "precious".
+                if (pPage != nullptr)
+                    pPage->SetPrecious(false);
+            }
+        }
+    }
+    catch (const uno::RuntimeException&)
+    {
+        DBG_UNHANDLED_EXCEPTION("sd");
+        pPage = nullptr;
+    }
+
+    return pPage;
+}
+
+::sd::DrawDocShell* TemplatePageObjectProvider::LoadDocument (const OUString& sFileName)
+{
+    SfxApplication* pSfxApp = SfxGetpApp();
+    std::unique_ptr<SfxItemSet> pSet(new SfxAllItemSet (pSfxApp->GetPool()));
+    pSet->Put (SfxBoolItem (SID_TEMPLATE, true));
+    pSet->Put (SfxBoolItem (SID_PREVIEW, true));
+    if (pSfxApp->LoadTemplate (mxDocumentShell, sFileName, std::move(pSet)))
+    {
+        mxDocumentShell = nullptr;
+    }
+    SfxObjectShell* pShell = mxDocumentShell;
+    return dynamic_cast< ::sd::DrawDocShell *>( pShell );
+}
+
+int TemplatePageObjectProvider::GetCostIndex()
+{
+    return 20;
+}
+
+//===== DefaultPageObjectProvider ==============================================
+
+DefaultPageObjectProvider::DefaultPageObjectProvider()
+{
+}
+
+SdPage* DefaultPageObjectProvider::operator () (SdDrawDocument* pContainerDocument)
+{
+    SdPage* pLocalMasterPage = nullptr;
+    if (pContainerDocument != nullptr)
+    {
+        SdPage* pLocalSlide = pContainerDocument->GetSdPage(0, PageKind::Standard);
+        if (pLocalSlide!=nullptr && pLocalSlide->TRG_HasMasterPage())
+            pLocalMasterPage = dynamic_cast<SdPage*>(&pLocalSlide->TRG_GetMasterPage());
+    }
+
+    if (pLocalMasterPage == nullptr)
+    {
+        SAL_WARN( "sd", "can not create master page for slide");
+    }
+
+    return pLocalMasterPage;
+}
+
+int DefaultPageObjectProvider::GetCostIndex()
+{
+    return 15;
+}
+
+//===== ExistingPageProvider ==================================================
+
+ExistingPageProvider::ExistingPageProvider (SdPage* pPage)
+    : mpPage(pPage)
+{
+}
+
+SdPage* ExistingPageProvider::operator() (SdDrawDocument*)
+{
+    return mpPage;
+}
+
+int ExistingPageProvider::GetCostIndex()
+{
+    return 0;
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageContainerProviders.hxx b/sd/source/ui/sidebar/MasterPageContainerProviders.hxx
new file mode 100644
index 000000000..b76076e15
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageContainerProviders.hxx
@@ -0,0 +1,175 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <rtl/ustring.hxx>
+#include <sfx2/objsh.hxx>
+
+class Image;
+class SdDrawDocument;
+class SdPage;
+namespace sd
+{
+class PreviewRenderer;
+}
+namespace sd
+{
+class DrawDocShell;
+}
+
+namespace sd::sidebar
+{
+/** Interface for a provider of page objects.  It is used by the
+    MasterPageDescriptor to create master page objects on demand.
+*/
+class PageObjectProvider
+{
+public:
+    /** Return a master page either by returning an already existing one, by
+        creating a new page, or by loading a document.
+        @param pDocument
+            The document of the MasterPageContainer.  It may be used to
+            create new pages.
+    */
+    virtual SdPage* operator()(SdDrawDocument* pDocument) = 0;
+
+    /** An abstract value for the expected cost of providing a master page
+        object.
+        @return
+            A value of 0 represents for the lowest cost, i.e. an almost
+            immediate return.  Positive values stand for higher costs.
+            Negative values are not supported.
+    */
+    virtual int GetCostIndex() = 0;
+
+protected:
+    ~PageObjectProvider() {}
+};
+
+class PreviewProvider
+{
+public:
+    /** Create a preview image in the specified width.
+        @param nWidth
+            Requested width of the preview.  The calling method can cope
+            with other sizes as well but the resulting image quality is
+            better when the returned image has the requested size.
+        @param pPage
+            Page object for which a preview is requested.  This may be NULL
+            when the page object is expensive to get and the PreviewProvider
+            does not need this object (NeedsPageObject() returns false.)
+        @param rRenderer
+            This PreviewRenderer may be used by the PreviewProvider to
+            create a preview image.
+    */
+    virtual Image operator()(int nWidth, SdPage* pPage, ::sd::PreviewRenderer& rRenderer) = 0;
+
+    /** Return a value that indicates how expensive the creation of a
+        preview image is.  The higher the returned value the more expensive
+        is the preview creation.  Return 0 when the preview is already
+        present and can be returned immediately.
+    */
+    virtual int GetCostIndex() = 0;
+
+    /** Return whether the page object passed is necessary to create a
+        preview.
+    */
+    virtual bool NeedsPageObject() = 0;
+
+protected:
+    ~PreviewProvider() {}
+};
+
+/** Provide previews of existing page objects by rendering them.
+*/
+class PagePreviewProvider : public PreviewProvider
+{
+public:
+    PagePreviewProvider();
+    virtual ~PagePreviewProvider() {}
+    virtual Image operator()(int nWidth, SdPage* pPage, ::sd::PreviewRenderer& rRenderer) override;
+    virtual int GetCostIndex() override;
+    virtual bool NeedsPageObject() override;
+
+private:
+};
+
+/** Provide master page objects for template documents for which only the
+    URL is given.
+*/
+class TemplatePageObjectProvider : public PageObjectProvider
+{
+public:
+    explicit TemplatePageObjectProvider(const OUString& rsURL);
+    virtual ~TemplatePageObjectProvider(){};
+    virtual SdPage* operator()(SdDrawDocument* pDocument) override;
+    virtual int GetCostIndex() override;
+
+private:
+    OUString msURL;
+    SfxObjectShellLock mxDocumentShell;
+    ::sd::DrawDocShell* LoadDocument(const OUString& sFileName);
+};
+
+/** Provide previews for template documents by loading the thumbnails from
+    the documents.
+*/
+class TemplatePreviewProvider : public PreviewProvider
+{
+public:
+    explicit TemplatePreviewProvider(const OUString& rsURL);
+    virtual ~TemplatePreviewProvider(){};
+    virtual Image operator()(int nWidth, SdPage* pPage, ::sd::PreviewRenderer& rRenderer) override;
+    virtual int GetCostIndex() override;
+    virtual bool NeedsPageObject() override;
+
+private:
+    OUString msURL;
+};
+
+/** Create an empty default master page.
+*/
+class DefaultPageObjectProvider : public PageObjectProvider
+{
+public:
+    DefaultPageObjectProvider();
+    virtual ~DefaultPageObjectProvider() {}
+    virtual SdPage* operator()(SdDrawDocument* pDocument) override;
+    virtual int GetCostIndex() override;
+};
+
+/** This implementation of the PageObjectProvider simply returns an already
+    existing master page object.
+*/
+class ExistingPageProvider : public PageObjectProvider
+{
+public:
+    explicit ExistingPageProvider(SdPage* pPage);
+    virtual ~ExistingPageProvider() {}
+    virtual SdPage* operator()(SdDrawDocument* pDocument) override;
+    virtual int GetCostIndex() override;
+
+private:
+    SdPage* mpPage;
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageContainerQueue.cxx b/sd/source/ui/sidebar/MasterPageContainerQueue.cxx
new file mode 100644
index 000000000..229f3d972
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageContainerQueue.cxx
@@ -0,0 +1,263 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "MasterPageContainerQueue.hxx"
+#include "MasterPageContainerProviders.hxx"
+
+#include <tools/IdleDetection.hxx>
+
+#include <set>
+
+namespace sd::sidebar {
+
+const sal_Int32 MasterPageContainerQueue::snDelayedCreationTimeout (15);
+const sal_Int32 MasterPageContainerQueue::snDelayedCreationTimeoutWhenNotIdle (100);
+const sal_Int32 MasterPageContainerQueue::snMasterPagePriorityBoost (5);
+const sal_Int32 MasterPageContainerQueue::snWaitForMoreRequestsPriorityThreshold (-10);
+sal_uInt32 MasterPageContainerQueue::snWaitForMoreRequestsCount(15);
+
+//===== MasterPageContainerQueue::PreviewCreationRequest ======================
+
+class MasterPageContainerQueue::PreviewCreationRequest
+{
+public:
+    PreviewCreationRequest (const SharedMasterPageDescriptor& rpDescriptor, int nPriority)
+        : mpDescriptor(rpDescriptor),
+          mnPriority(nPriority)
+    {}
+    SharedMasterPageDescriptor mpDescriptor;
+    int mnPriority;
+    class Compare
+    {
+    public:
+        bool operator() (const PreviewCreationRequest& r1,const PreviewCreationRequest& r2) const
+        {
+            if (r1.mnPriority != r2.mnPriority)
+            {
+                // Prefer requests with higher priority.
+                return r1.mnPriority > r2.mnPriority;
+            }
+            else
+            {
+                // Prefer tokens that have been earlier created (those with lower
+                // value).
+                return r1.mpDescriptor->maToken < r2.mpDescriptor->maToken;
+            }
+        }
+    };
+    class CompareToken
+    {
+    public:
+        MasterPageContainer::Token maToken;
+        explicit CompareToken(MasterPageContainer::Token aToken) : maToken(aToken) {}
+        bool operator() (const PreviewCreationRequest& rRequest) const
+            { return maToken==rRequest.mpDescriptor->maToken; }
+    };
+};
+
+//===== MasterPageContainerQueue::RequestQueue ================================
+
+class MasterPageContainerQueue::RequestQueue
+    : public ::std::set<PreviewCreationRequest,PreviewCreationRequest::Compare>
+{
+public:
+    RequestQueue() {}
+};
+
+//===== MasterPageContainerQueue ==============================================
+
+MasterPageContainerQueue* MasterPageContainerQueue::Create (
+    const std::weak_ptr<ContainerAdapter>& rpContainer)
+{
+    MasterPageContainerQueue* pQueue = new MasterPageContainerQueue(rpContainer);
+    pQueue->LateInit();
+    return pQueue;
+}
+
+MasterPageContainerQueue::MasterPageContainerQueue (
+    const std::weak_ptr<ContainerAdapter>& rpContainer)
+    : mpWeakContainer(rpContainer),
+      mpRequestQueue(new RequestQueue()),
+      maDelayedPreviewCreationTimer("sd MasterPageContainerQueue maDelayedPreviewCreationTimer"),
+      mnRequestsServedCount(0)
+{
+}
+
+MasterPageContainerQueue::~MasterPageContainerQueue()
+{
+    maDelayedPreviewCreationTimer.Stop();
+    while ( ! mpRequestQueue->empty())
+        mpRequestQueue->erase(mpRequestQueue->begin());
+}
+
+void MasterPageContainerQueue::LateInit()
+{
+    // Set up the timer for the delayed creation of preview bitmaps.
+    maDelayedPreviewCreationTimer.SetTimeout (snDelayedCreationTimeout);
+    maDelayedPreviewCreationTimer.SetInvokeHandler(
+        LINK(this,MasterPageContainerQueue,DelayedPreviewCreation) );
+}
+
+bool MasterPageContainerQueue::RequestPreview (const SharedMasterPageDescriptor& rpDescriptor)
+{
+    bool bSuccess (false);
+    if (rpDescriptor
+        && rpDescriptor->maLargePreview.GetSizePixel().Width() == 0)
+    {
+        sal_Int32 nPriority (CalculatePriority(rpDescriptor));
+
+        // Add a new or replace an existing request.
+        RequestQueue::iterator iRequest (::std::find_if(
+            mpRequestQueue->begin(),
+            mpRequestQueue->end(),
+            PreviewCreationRequest::CompareToken(rpDescriptor->maToken)));
+        // When a request for the same token exists then the lowest of the
+        // two priorities is used.
+        if (iRequest != mpRequestQueue->end())
+            if (iRequest->mnPriority < nPriority)
+            {
+                mpRequestQueue->erase(iRequest);
+                iRequest = mpRequestQueue->end();
+            }
+
+        // Add a new request when none exists (or has just been erased).
+        if (iRequest == mpRequestQueue->end())
+        {
+            mpRequestQueue->insert(PreviewCreationRequest(rpDescriptor,nPriority));
+            maDelayedPreviewCreationTimer.Start();
+            bSuccess = true;
+        }
+    }
+    return bSuccess;
+}
+
+sal_Int32 MasterPageContainerQueue::CalculatePriority (
+    const SharedMasterPageDescriptor& rpDescriptor)
+{
+    sal_Int32 nPriority;
+
+    // The cost is used as a starting value.
+    int nCost (0);
+    if (rpDescriptor->mpPreviewProvider != nullptr)
+    {
+        nCost = rpDescriptor->mpPreviewProvider->GetCostIndex();
+        if (rpDescriptor->mpPreviewProvider->NeedsPageObject())
+            if (rpDescriptor->mpPageObjectProvider != nullptr)
+                nCost += rpDescriptor->mpPageObjectProvider->GetCostIndex();
+    }
+
+    // Its negative value is used so that requests with a low cost are
+    // preferred over those with high costs.
+    nPriority = -nCost;
+
+    // Add a term that introduces an order based on the appearance in the
+    // AllMasterPagesSelector.
+    nPriority -= rpDescriptor->maToken / 3;
+
+    // Process requests for the CurrentMasterPagesSelector first.
+    if (rpDescriptor->meOrigin == MasterPageContainer::MASTERPAGE)
+        nPriority += snMasterPagePriorityBoost;
+
+    return nPriority;
+}
+
+IMPL_LINK(MasterPageContainerQueue, DelayedPreviewCreation, Timer*, pTimer, void)
+{
+    bool bIsShowingFullScreenShow (false);
+    bool bWaitForMoreRequests (false);
+
+    do
+    {
+        if (mpRequestQueue->empty())
+            break;
+
+        // First check whether the system is idle.
+        tools::IdleState nIdleState (tools::IdleDetection::GetIdleState(nullptr));
+        if (nIdleState != tools::IdleState::Idle)
+        {
+            if (nIdleState & tools::IdleState::FullScreenShowActive)
+                bIsShowingFullScreenShow = true;
+            break;
+        }
+
+        PreviewCreationRequest aRequest (*mpRequestQueue->begin());
+
+        // Check if the request should really be processed right now.
+        // Reasons to not do it are when its cost is high and not many other
+        // requests have been inserted into the queue that would otherwise
+        // be processed first.
+        if (aRequest.mnPriority < snWaitForMoreRequestsPriorityThreshold
+            && (mnRequestsServedCount+mpRequestQueue->size() < snWaitForMoreRequestsCount))
+        {
+            // Wait for more requests before this one is processed.  Note
+            // that the queue processing is not started anew when this
+            // method is left.  That is done when the next request is
+            // inserted.
+            bWaitForMoreRequests = true;
+            break;
+        }
+
+        mpRequestQueue->erase(mpRequestQueue->begin());
+
+        if (aRequest.mpDescriptor)
+        {
+            mnRequestsServedCount += 1;
+            if ( ! mpWeakContainer.expired())
+            {
+                std::shared_ptr<ContainerAdapter> pContainer (mpWeakContainer);
+                if (pContainer != nullptr)
+                    pContainer->UpdateDescriptor(aRequest.mpDescriptor,false,true,true);
+            }
+        }
+    }
+    while (false);
+
+    if (!mpRequestQueue->empty() && ! bWaitForMoreRequests)
+    {
+        int nTimeout (snDelayedCreationTimeout);
+        if (bIsShowingFullScreenShow)
+            nTimeout = snDelayedCreationTimeoutWhenNotIdle;
+        maDelayedPreviewCreationTimer.SetTimeout(nTimeout);
+        pTimer->Start();
+    }
+}
+
+bool MasterPageContainerQueue::HasRequest (MasterPageContainer::Token aToken) const
+{
+    return std::any_of(
+        mpRequestQueue->begin(),
+        mpRequestQueue->end(),
+        PreviewCreationRequest::CompareToken(aToken));
+}
+
+bool MasterPageContainerQueue::IsEmpty() const
+{
+    return mpRequestQueue->empty();
+}
+
+void MasterPageContainerQueue::ProcessAllRequests()
+{
+    snWaitForMoreRequestsCount = 0;
+    if (!mpRequestQueue->empty())
+        maDelayedPreviewCreationTimer.Start();
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageContainerQueue.hxx b/sd/source/ui/sidebar/MasterPageContainerQueue.hxx
new file mode 100644
index 000000000..6b9b0adca
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageContainerQueue.hxx
@@ -0,0 +1,131 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include "MasterPageContainer.hxx"
+#include "MasterPageDescriptor.hxx"
+
+#include <vcl/timer.hxx>
+
+#include <memory>
+
+namespace sd::sidebar {
+
+/** The queue stores and processes all requests from a MasterPageContainer
+    for the creation of previews.
+    The order of request processing and its timing is controlled by a
+    heuristic that uses values given with each request and which is
+    controlled by various parameters that are described below.
+*/
+class MasterPageContainerQueue final
+{
+public:
+    class ContainerAdapter {
+    public:
+        virtual bool UpdateDescriptor (
+            const SharedMasterPageDescriptor& rpDescriptor,
+            bool bForcePageObject,
+            bool bForcePreview,
+            bool bSendEvents) = 0;
+
+    protected:
+        ~ContainerAdapter() {}
+    };
+
+    static MasterPageContainerQueue* Create (
+        const std::weak_ptr<ContainerAdapter>& rpContainer);
+    ~MasterPageContainerQueue();
+
+    /** This method is typically called for entries in the container for
+        which GetPreviewState() returns OS_CREATABLE.  The creation of the
+        preview is then scheduled to be executed asynchronously at a later
+        point in time.  When the preview is available the change listeners
+        will be notified.
+    */
+    bool RequestPreview (const SharedMasterPageDescriptor& rDescriptor);
+
+    /** Return <TRUE/> when there is a request currently in the queue for
+        the given token.
+    */
+    bool HasRequest (MasterPageContainer::Token aToken) const;
+
+    /** Return <TRUE/> when there is at least one request in the queue.
+    */
+    bool IsEmpty() const;
+
+    /** After this call the queue does not wait anymore for requests with
+        higher priority when only a small number of requests with lower
+        priority are present.  This method should be called when all
+        templates are inserted into the MasterPageContainer.
+    */
+    void ProcessAllRequests();
+
+private:
+    std::weak_ptr<ContainerAdapter> mpWeakContainer;
+    class PreviewCreationRequest;
+    class RequestQueue;
+    std::unique_ptr<RequestQueue> mpRequestQueue;
+    Timer maDelayedPreviewCreationTimer;
+    sal_uInt32 mnRequestsServedCount;
+
+    // There are a couple of values that define various aspects of the
+    // heuristic that defines the order and timing in which requests for
+    // preview creation are processed.
+
+    /** The time to wait (in milliseconds) between the creation of previews.
+    */
+    static const sal_Int32 snDelayedCreationTimeout;
+
+    /** The time to wait when the system is not idle.
+    */
+    static const sal_Int32 snDelayedCreationTimeoutWhenNotIdle;
+
+    /** Requests for previews of master pages in a document have their
+        priority increased by this value.
+    */
+    static const sal_Int32 snMasterPagePriorityBoost;
+
+    /** When only requests which a priority lower than this threshold exist
+        and not many requests have been made yet then wait with processing
+        them until more requests are present.
+    */
+    static const sal_Int32 snWaitForMoreRequestsPriorityThreshold;
+
+    /** When only requests which a priority lower than a threshold exist
+        and not more requests than this number have been made or already
+        processed then wait with processing them until more requests are
+        present.
+    */
+    static sal_uInt32 snWaitForMoreRequestsCount;
+
+    explicit MasterPageContainerQueue (const std::weak_ptr<ContainerAdapter>& rpContainer);
+    void LateInit();
+
+    /** Calculate the priority that defines the order in which requests
+        are processed.
+    */
+    static sal_Int32 CalculatePriority (const SharedMasterPageDescriptor& rDescriptor);
+
+    DECL_LINK(DelayedPreviewCreation, Timer *, void);
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageDescriptor.cxx b/sd/source/ui/sidebar/MasterPageDescriptor.cxx
new file mode 100644
index 000000000..2c0c23eb7
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageDescriptor.cxx
@@ -0,0 +1,341 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <memory>
+#include "MasterPageDescriptor.hxx"
+#include "MasterPageContainerProviders.hxx"
+
+#include "DocumentHelper.hxx"
+#include <PreviewRenderer.hxx>
+#include <sdpage.hxx>
+#include <tools/urlobj.hxx>
+#include <sal/log.hxx>
+
+namespace sd::sidebar {
+
+//===== MasterPageDescriptor ==================================================
+
+MasterPageDescriptor::MasterPageDescriptor (
+    MasterPageContainer::Origin eOrigin,
+    const sal_Int32 nTemplateIndex,
+    std::u16string_view rsURL,
+    const OUString& rsPageName,
+    const OUString& rsStyleName,
+    const bool bIsPrecious,
+    const std::shared_ptr<PageObjectProvider>& rpPageObjectProvider,
+    const std::shared_ptr<PreviewProvider>& rpPreviewProvider)
+    : maToken(MasterPageContainer::NIL_TOKEN),
+      meOrigin(eOrigin),
+      msURL(INetURLObject(rsURL).GetMainURL(INetURLObject::DecodeMechanism::Unambiguous)),
+      msPageName(rsPageName),
+      msStyleName(rsStyleName),
+      mbIsPrecious(bIsPrecious),
+      mpMasterPage(nullptr),
+      mpSlide(nullptr),
+      mpPreviewProvider(rpPreviewProvider),
+      mpPageObjectProvider(rpPageObjectProvider),
+      mnTemplateIndex(nTemplateIndex),
+      meURLClassification(URLCLASS_UNDETERMINED),
+      mnUseCount(0)
+{
+}
+
+void MasterPageDescriptor::SetToken (MasterPageContainer::Token aToken)
+{
+    maToken = aToken;
+}
+
+const Image& MasterPageDescriptor::GetPreview (MasterPageContainer::PreviewSize eSize) const
+{
+    if (eSize == MasterPageContainer::SMALL)
+        return maSmallPreview;
+    else
+        return maLargePreview;
+}
+
+::std::unique_ptr<std::vector<MasterPageContainerChangeEvent::EventType> >
+    MasterPageDescriptor::Update (
+        const MasterPageDescriptor& rDescriptor)
+{
+    bool bDataChanged (false);
+    bool bIndexChanged (false);
+    bool bPreviewChanged (false);
+
+    if (meOrigin==MasterPageContainer::UNKNOWN
+        && rDescriptor.meOrigin!=MasterPageContainer::UNKNOWN)
+    {
+        meOrigin = rDescriptor.meOrigin;
+        bIndexChanged = true;
+    }
+
+    if (msURL.isEmpty() && !rDescriptor.msURL.isEmpty())
+    {
+        msURL = rDescriptor.msURL;
+        bDataChanged = true;
+    }
+
+    if (msPageName.isEmpty() && !rDescriptor.msPageName.isEmpty())
+    {
+        msPageName = rDescriptor.msPageName;
+        bDataChanged = true;
+    }
+
+    if (msStyleName.isEmpty() && !rDescriptor.msStyleName.isEmpty())
+    {
+        msStyleName = rDescriptor.msStyleName;
+        bDataChanged = true;
+    }
+
+    if (mpPageObjectProvider == nullptr && rDescriptor.mpPageObjectProvider != nullptr)
+    {
+        mpPageObjectProvider = rDescriptor.mpPageObjectProvider;
+        bDataChanged = true;
+    }
+
+    if (mpPreviewProvider == nullptr && rDescriptor.mpPreviewProvider != nullptr)
+    {
+        mpPreviewProvider = rDescriptor.mpPreviewProvider;
+        bPreviewChanged = true;
+    }
+
+    if (mnTemplateIndex<0 && rDescriptor.mnTemplateIndex>=0)
+    {
+         mnTemplateIndex = rDescriptor.mnTemplateIndex;
+         bIndexChanged = true;
+    }
+
+     // Prepare the list of event types that will be returned.
+    ::std::unique_ptr<std::vector<MasterPageContainerChangeEvent::EventType> > pResult;
+    if (bDataChanged || bIndexChanged || bPreviewChanged)
+    {
+         pResult.reset(new std::vector<MasterPageContainerChangeEvent::EventType>);
+         if (bDataChanged)
+             pResult->push_back(MasterPageContainerChangeEvent::EventType::DATA_CHANGED);
+         if (bIndexChanged)
+             pResult->push_back(MasterPageContainerChangeEvent::EventType::INDEX_CHANGED);
+         if (bPreviewChanged)
+             pResult->push_back(MasterPageContainerChangeEvent::EventType::PREVIEW_CHANGED);
+    }
+
+    return pResult;
+}
+
+int MasterPageDescriptor::UpdatePageObject (
+    sal_Int32 nCostThreshold,
+    SdDrawDocument* pDocument)
+{
+    int nModified = 0;
+
+    // Update the page object when that is not yet known.
+    if (mpMasterPage == nullptr && mpPageObjectProvider != nullptr
+        && (nCostThreshold < 0 || mpPageObjectProvider->GetCostIndex() <= nCostThreshold))
+    {
+        // Note that pDocument may be NULL.
+
+        SdPage* pPage = (*mpPageObjectProvider)(pDocument);
+        if (meOrigin == MasterPageContainer::MASTERPAGE)
+        {
+            mpMasterPage = pPage;
+            if (mpMasterPage != nullptr)
+                mpMasterPage->SetPrecious(mbIsPrecious);
+        }
+        else
+        {
+            // Master pages from templates are copied into the local document.
+            if (pDocument != nullptr)
+                mpMasterPage = DocumentHelper::CopyMasterPageToLocalDocument(*pDocument,pPage);
+            mpSlide = DocumentHelper::GetSlideForMasterPage(mpMasterPage);
+        }
+
+        if (mpMasterPage != nullptr)
+        {
+            // Update page name and style name.
+            if (msPageName.isEmpty())
+                msPageName = mpMasterPage->GetName();
+            msStyleName = mpMasterPage->GetName();
+
+            // Delete an existing substitution. The next request for a preview
+            // will create the real one.
+            maSmallPreview = Image();
+            maLargePreview = Image();
+            mpPreviewProvider = std::make_shared<PagePreviewProvider>();
+        }
+        else
+        {
+            SAL_WARN( "sd", "UpdatePageObject: master page is NULL");
+            return -1;
+        }
+
+        nModified = 1;
+    }
+
+    return nModified;
+}
+
+bool MasterPageDescriptor::UpdatePreview (
+    sal_Int32 nCostThreshold,
+    const Size& rSmallSize,
+    const Size& rLargeSize,
+    ::sd::PreviewRenderer& rRenderer)
+{
+    bool bModified (false);
+
+    // Update the preview when that is not yet known.
+    if (maLargePreview.GetSizePixel().Width() == 0 && mpPreviewProvider != nullptr
+        && (nCostThreshold < 0 || mpPreviewProvider->GetCostIndex() <= nCostThreshold))
+    {
+        SdPage* pPage = mpSlide;
+        if (pPage == nullptr)
+        {
+            pPage = mpMasterPage;
+        }
+        //TODO: Notify LOOL of preview updates.
+        maLargePreview = (*mpPreviewProvider)(
+            rLargeSize.Width(),
+            pPage,
+            rRenderer);
+        if (maLargePreview.GetSizePixel().Width() > 0)
+        {
+            // Create the small preview by scaling the large one down.
+            maSmallPreview = rRenderer.ScaleBitmap(
+                maLargePreview.GetBitmapEx(),
+                rSmallSize.Width());
+            // The large preview may not have the desired width.  Scale it
+            // accordingly.
+            if (maLargePreview.GetSizePixel().Width() != rLargeSize.Width())
+                maLargePreview = rRenderer.ScaleBitmap(
+                    maLargePreview.GetBitmapEx(),
+                    rLargeSize.Width());
+            bModified = true;
+        }
+    }
+
+    return bModified;
+}
+
+MasterPageDescriptor::URLClassification MasterPageDescriptor::GetURLClassification()
+{
+    if (meURLClassification == URLCLASS_UNDETERMINED)
+    {
+        if (msURL.isEmpty())
+            meURLClassification = URLCLASS_UNKNOWN;
+        else if (msURL.indexOf("presnt")>=0)
+        {
+            meURLClassification = URLCLASS_PRESENTATION;
+        }
+        else if (msURL.indexOf("layout")>=0)
+        {
+            meURLClassification = URLCLASS_LAYOUT;
+        }
+        else if (msURL.indexOf("educate")>=0)
+        {
+            meURLClassification = URLCLASS_OTHER;
+        }
+        else
+        {
+            meURLClassification = URLCLASS_USER;
+        }
+    }
+
+    return meURLClassification;
+}
+
+//===== URLComparator =========================================================
+
+MasterPageDescriptor::URLComparator::URLComparator (const OUString& sURL)
+    : msURL(sURL)
+{
+}
+
+bool MasterPageDescriptor::URLComparator::operator() (
+    const SharedMasterPageDescriptor& rDescriptor)
+{
+    if (!rDescriptor)
+        return false;
+    else
+        return rDescriptor->msURL == msURL;
+}
+
+// ===== StyleNameComparator ==================================================
+
+MasterPageDescriptor::StyleNameComparator::StyleNameComparator (const OUString& sStyleName)
+    : msStyleName(sStyleName)
+{
+}
+
+bool MasterPageDescriptor::StyleNameComparator::operator() (
+    const SharedMasterPageDescriptor& rDescriptor)
+{
+    if (!rDescriptor)
+        return false;
+    else
+        return rDescriptor->msStyleName == msStyleName;
+}
+
+//===== PageObjectComparator ==================================================
+
+MasterPageDescriptor::PageObjectComparator::PageObjectComparator (const SdPage* pPageObject)
+    : mpMasterPage(pPageObject)
+{
+}
+
+bool MasterPageDescriptor::PageObjectComparator::operator() (
+    const SharedMasterPageDescriptor& rDescriptor)
+{
+    if (!rDescriptor)
+        return false;
+    else
+        return rDescriptor->mpMasterPage==mpMasterPage;
+}
+
+//===== AllComparator =========================================================
+
+MasterPageDescriptor::AllComparator::AllComparator(const SharedMasterPageDescriptor& rDescriptor)
+    : mpDescriptor(rDescriptor)
+{
+}
+
+bool MasterPageDescriptor::AllComparator::operator() (const SharedMasterPageDescriptor&rDescriptor)
+{
+    if (!rDescriptor)
+        return false;
+    else
+    {
+        // Take URL, page name, style name, and page object into account
+        // when comparing two descriptors.  When two descriptors are
+        // identical in any of these values then there are thought of as
+        // equivalent.  Only the Origin has to be the same in both
+        // descriptors.
+        return mpDescriptor->meOrigin == rDescriptor->meOrigin
+               && ((!mpDescriptor->msURL.isEmpty() && mpDescriptor->msURL == rDescriptor->msURL)
+                   || (!mpDescriptor->msPageName.isEmpty()
+                       && mpDescriptor->msPageName == rDescriptor->msPageName)
+                   || (!mpDescriptor->msStyleName.isEmpty()
+                       && mpDescriptor->msStyleName == rDescriptor->msStyleName)
+                   || (mpDescriptor->mpMasterPage != nullptr
+                       && mpDescriptor->mpMasterPage == rDescriptor->mpMasterPage)
+                   || (mpDescriptor->mpPageObjectProvider != nullptr
+                       && rDescriptor->mpPageObjectProvider != nullptr
+                       && mpDescriptor->mpPageObjectProvider == rDescriptor->mpPageObjectProvider));
+    }
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageDescriptor.hxx b/sd/source/ui/sidebar/MasterPageDescriptor.hxx
new file mode 100644
index 000000000..62717e528
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageDescriptor.hxx
@@ -0,0 +1,231 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include "MasterPageContainer.hxx"
+#include <memory>
+
+namespace sd { class PreviewRenderer; }
+class SdDrawDocument;
+
+namespace sd::sidebar {
+
+class PageObjectProvider;
+class PreviewProvider;
+
+class MasterPageDescriptor;
+typedef std::shared_ptr<MasterPageDescriptor> SharedMasterPageDescriptor;
+
+/** A collection of data that is stored for every master page in the
+    MasterpageContainer.
+*/
+class MasterPageDescriptor
+{
+public:
+    MasterPageDescriptor (
+        MasterPageContainer::Origin eOrigin,
+        const sal_Int32 nTemplateIndex,
+        std::u16string_view rURL,
+        const OUString& rPageName,
+        const OUString& rStyleName,
+        const bool bIsPrecious,
+        const std::shared_ptr<PageObjectProvider>& rpPageObjectProvider,
+        const std::shared_ptr<PreviewProvider>& rpPreviewProvider);
+
+    void SetToken (MasterPageContainer::Token aToken);
+
+    /** Update the called MasterPageDescriptor object with values from the
+        given one.  Only those values are updated that have default values
+        in the called object and that have non-default values in the given
+        one.
+        @return
+            Returns a list of event types for which event notifications have
+            to be sent to listeners.  The list may be empty or NULL.
+    */
+    ::std::unique_ptr<std::vector<MasterPageContainerChangeEvent::EventType> >
+        Update (
+            const MasterPageDescriptor& rDescriptor);
+
+    /** This convenience method returns either a small or a large preview,
+        depending on the given size specifier.
+        Note that the previews are not created when they are not present.
+        @return
+            The returned preview may be empty.
+    */
+    const Image& GetPreview (MasterPageContainer::PreviewSize ePreviewSize) const;
+
+    /** Use the PreviewProvider to get access to a preview of the master
+        page.
+
+        Note that this is only done, when either bForce is <TRUE/> or
+        the PreviewProvider::GetCostIndex() returns 0.
+
+        The small preview is created by scaling the large one, not by
+        calling PreviewProvider::operator() a second time.
+
+        It is the responsibility of the caller to call UpdatePageObject()
+        before calling this method  when the PreviewProvider can only work
+        when the master page object is present, i.e. its NeedsPageObject()
+        method returns <TRUE/>.
+
+        @param nCostThreshold
+            When this is zero or positive then the preview is created only
+            when the preview provider has a cost equal to or smaller than
+            this threshold.  A negative value forces the preview to be
+            created, regardless of the cost.
+        @param rSmallSize
+            Size of the small preview.
+        @param rLargeSize
+            Size of the large preview.
+        @param rRenderer
+            A PreviewRenderer object that may be used to create a preview.
+        @return
+            When the previews are successfully provided then <TRUE/> is
+            returned.
+    */
+    bool UpdatePreview (
+        sal_Int32 nCostThreshold,
+        const Size& rSmallSize,
+        const Size& rLargeSize,
+        ::sd::PreviewRenderer& rRenderer);
+
+    /** Use the PageObjectProvider to get access to the master page object.
+
+        Note that this is only done, when either bForce is <TRUE/> or the
+        PreviewProvider::GetCostIndex() returns 0.
+
+        @param nCostThreshold
+            When this is zero or positive then the page object is created
+            only when the page object provider has a cost equal to or
+            smaller than this threshold.  A negative value forces the
+            page object be created, regardless of the cost.
+        @param pDocument
+            This document of the MasterPageContainer may be used to create
+            a page object with or store one in.
+        @return
+            When the master page object is successfully provided then
+            1 is returned, on no change then a 0 is provided,
+            on a masterpage-error a -1 is provided.
+    */
+    int UpdatePageObject (
+        sal_Int32 nCostThreshold,
+        SdDrawDocument* pDocument);
+
+    enum URLClassification {
+        URLCLASS_USER,
+        URLCLASS_LAYOUT,
+        URLCLASS_PRESENTATION,
+        URLCLASS_OTHER,
+        URLCLASS_UNKNOWN,
+        URLCLASS_UNDETERMINED
+    };
+
+    URLClassification GetURLClassification();
+
+    /** The Token under which the MasterPageContainer gives access to the
+        object.
+    */
+    MasterPageContainer::Token maToken;
+
+    /** A rough specification of the origin of the master page.
+    */
+    MasterPageContainer::Origin meOrigin;
+
+    /** The URL is not empty for master pages loaded from a template
+        document.
+    */
+    OUString msURL;
+
+    /** Taken from the title of the template file.
+    */
+    OUString msPageName;
+
+    /** Taken from the master page object.
+    */
+    OUString msStyleName;
+
+    const bool mbIsPrecious;
+
+    /** The actual master page.
+    */
+    SdPage* mpMasterPage;
+
+    /** A slide that uses the master page.
+    */
+    SdPage* mpSlide;
+
+    /** A small (the default size) preview of the master page.  May be
+        empty.  When this smaller preview is not empty then the larger one
+        is not empty, too.
+    */
+    Image maSmallPreview;
+
+    /** A large preview of the master page.  May be empty.  When this larger
+        preview is not empty then the smaller one is not empty, too.
+    */
+    Image maLargePreview;
+
+    /** The preview provider. May be empty.  May be replaced during the
+        lifetime of a MasterPageDescriptor object.
+    */
+    std::shared_ptr<PreviewProvider> mpPreviewProvider;
+
+    /** The master page provider.  May be empty.  May be replaced during
+        the lifetime of a MasterPageDescriptor object.
+    */
+    std::shared_ptr<PageObjectProvider> mpPageObjectProvider;
+
+    /** This index represents the order in which templates are provided via
+        the TemplateScanner.  It defines the order in which the entries in
+        the AllMasterPagesSelector are displayed.  The default value is -1.
+    */
+    sal_Int32 mnTemplateIndex;
+
+    URLClassification meURLClassification;
+
+    sal_Int32 mnUseCount;
+
+    class URLComparator { public:
+        OUString msURL;
+        explicit URLComparator (const OUString& sURL);
+        bool operator() (const SharedMasterPageDescriptor& rDescriptor);
+    };
+    class StyleNameComparator { public:
+        OUString msStyleName;
+        explicit StyleNameComparator (const OUString& sStyleName);
+        bool operator() (const SharedMasterPageDescriptor& rDescriptor);
+    };
+    class PageObjectComparator { public:
+        const SdPage* mpMasterPage;
+        explicit PageObjectComparator (const SdPage* pPageObject);
+        bool operator() (const SharedMasterPageDescriptor& rDescriptor);
+    };
+    class AllComparator { public:
+        explicit AllComparator(const SharedMasterPageDescriptor& rDescriptor);
+        bool operator() (const SharedMasterPageDescriptor& rDescriptor);
+    private:
+        SharedMasterPageDescriptor mpDescriptor;
+    };
+
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPageObserver.cxx b/sd/source/ui/sidebar/MasterPageObserver.cxx
new file mode 100644
index 000000000..017a0bcdf
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPageObserver.cxx
@@ -0,0 +1,317 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <MasterPageObserver.hxx>
+
+#include <algorithm>
+#include <iterator>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include <set>
+#include <unordered_map>
+#include <memory>
+#include <vector>
+#include <svl/lstner.hxx>
+#include <osl/doublecheckedlocking.h>
+#include <osl/getglobalmutex.hxx>
+#include <tools/debug.hxx>
+
+namespace sd {
+
+class MasterPageObserver::Implementation
+    : public SfxListener
+{
+public:
+    /** The single instance of this class.  It is created on demand when
+        Instance() is called for the first time.
+    */
+    static MasterPageObserver* mpInstance;
+
+    /** The master page observer will listen to events of this document and
+        detect changes of the use of master pages.
+    */
+    void RegisterDocument (SdDrawDocument& rDocument);
+
+    /** The master page observer will stop to listen to events of this
+        document.
+    */
+    void UnregisterDocument (SdDrawDocument& rDocument);
+
+    /** Add a listener that is informed of master pages that are newly
+        assigned to slides or become unassigned.
+        @param rEventListener
+            The event listener to call for future events.  Call
+            RemoveEventListener() before the listener is destroyed.
+    */
+    void AddEventListener (const Link<MasterPageObserverEvent&,void>& rEventListener);
+
+    /** Remove the given listener from the list of listeners.
+        @param rEventListener
+            After this method returns the given listener is not called back
+            from this object.  Passing a listener that has not
+            been registered before is safe and is silently ignored.
+    */
+    void RemoveEventListener (const Link<MasterPageObserverEvent&,void>& rEventListener);
+
+private:
+    ::std::vector<Link<MasterPageObserverEvent&,void>> maListeners;
+
+    struct DrawDocHash {
+        size_t operator()(SdDrawDocument* argument) const
+        { return reinterpret_cast<sal_uIntPtr>(argument); }
+    };
+    typedef std::unordered_map<SdDrawDocument*,
+                            MasterPageObserver::MasterPageNameSet,
+                            DrawDocHash>
+        MasterPageContainer;
+    MasterPageContainer maUsedMasterPages;
+
+    virtual void Notify(
+        SfxBroadcaster& rBroadcaster,
+        const SfxHint& rHint) override;
+
+    void AnalyzeUsedMasterPages (SdDrawDocument& rDocument);
+
+    void SendEvent (MasterPageObserverEvent& rEvent);
+};
+
+MasterPageObserver* MasterPageObserver::Implementation::mpInstance = nullptr;
+
+//===== MasterPageObserver ====================================================
+
+MasterPageObserver&  MasterPageObserver::Instance()
+{
+    if (Implementation::mpInstance == nullptr)
+    {
+        ::osl::GetGlobalMutex aMutexFunctor;
+        ::osl::MutexGuard aGuard (aMutexFunctor());
+        if (Implementation::mpInstance == nullptr)
+        {
+            MasterPageObserver* pInstance = new MasterPageObserver ();
+            SdGlobalResourceContainer::Instance().AddResource (
+                ::std::unique_ptr<SdGlobalResource>(pInstance));
+            OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
+            Implementation::mpInstance = pInstance;
+        }
+    }
+    else
+    {
+        OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
+    }
+
+    DBG_ASSERT(Implementation::mpInstance!=nullptr,
+        "MasterPageObserver::Instance(): instance is NULL");
+    return *Implementation::mpInstance;
+}
+
+void MasterPageObserver::RegisterDocument (SdDrawDocument& rDocument)
+{
+    mpImpl->RegisterDocument (rDocument);
+}
+
+void MasterPageObserver::UnregisterDocument (SdDrawDocument& rDocument)
+{
+    mpImpl->UnregisterDocument (rDocument);
+}
+
+void MasterPageObserver::AddEventListener (const Link<MasterPageObserverEvent&,void>& rEventListener)
+{
+
+    mpImpl->AddEventListener (rEventListener);
+}
+
+void MasterPageObserver::RemoveEventListener (const Link<MasterPageObserverEvent&,void>& rEventListener)
+{
+    mpImpl->RemoveEventListener (rEventListener);
+}
+
+MasterPageObserver::MasterPageObserver()
+    : mpImpl (new Implementation)
+{}
+
+MasterPageObserver::~MasterPageObserver()
+{}
+
+//===== MasterPageObserver::Implementation ====================================
+
+void MasterPageObserver::Implementation::RegisterDocument (
+    SdDrawDocument& rDocument)
+{
+    // Gather the names of all the master pages in the given document.
+    MasterPageContainer::mapped_type aMasterPageSet;
+    sal_uInt16 nMasterPageCount = rDocument.GetMasterSdPageCount(PageKind::Standard);
+    for (sal_uInt16 nIndex=0; nIndex<nMasterPageCount; nIndex++)
+    {
+        SdPage* pMasterPage = rDocument.GetMasterSdPage (nIndex, PageKind::Standard);
+        if (pMasterPage != nullptr)
+            aMasterPageSet.insert (pMasterPage->GetName());
+    }
+
+    bool bAlreadyExists = maUsedMasterPages.find(&rDocument) != maUsedMasterPages.end();
+    maUsedMasterPages[&rDocument] = aMasterPageSet;
+
+    if (!bAlreadyExists)
+        StartListening (rDocument);
+}
+
+void MasterPageObserver::Implementation::UnregisterDocument (
+    SdDrawDocument& rDocument)
+{
+    EndListening (rDocument);
+
+    MasterPageContainer::iterator aMasterPageDescriptor(maUsedMasterPages.find(&rDocument));
+    if(aMasterPageDescriptor != maUsedMasterPages.end())
+        maUsedMasterPages.erase(aMasterPageDescriptor);
+}
+
+void MasterPageObserver::Implementation::AddEventListener (
+    const Link<MasterPageObserverEvent&,void>& rEventListener)
+{
+    if (::std::find (
+        maListeners.begin(),
+        maListeners.end(),
+        rEventListener) != maListeners.end())
+        return;
+
+    maListeners.push_back (rEventListener);
+
+    // Tell the new listener about all the master pages that are
+    // currently in use.
+    for (const auto& rDocument : maUsedMasterPages)
+    {
+        ::std::set<OUString>::reverse_iterator aNameIterator;
+        for (aNameIterator=rDocument.second.rbegin();
+             aNameIterator!=rDocument.second.rend();
+             ++aNameIterator)
+        {
+          MasterPageObserverEvent aEvent (
+              MasterPageObserverEvent::ET_MASTER_PAGE_EXISTS,
+              *aNameIterator);
+          SendEvent (aEvent);
+        }
+    }
+}
+
+void MasterPageObserver::Implementation::RemoveEventListener (
+    const Link<MasterPageObserverEvent&,void>& rEventListener)
+{
+    maListeners.erase (
+        ::std::find (
+            maListeners.begin(),
+            maListeners.end(),
+            rEventListener));
+}
+
+void MasterPageObserver::Implementation::Notify(
+    SfxBroadcaster& rBroadcaster,
+    const SfxHint& rHint)
+{
+    if (rHint.GetId() != SfxHintId::ThisIsAnSdrHint)
+        return;
+    const SdrHint* pSdrHint = static_cast<const SdrHint*>(&rHint);
+
+    switch (pSdrHint->GetKind())
+    {
+        case SdrHintKind::PageOrderChange:
+            // Process the modified set of pages only when the number of
+            // standard and notes master pages are equal.  This test
+            // filters out events that are sent in between the insertion
+            // of a new standard master page and a new notes master
+            // page.
+            if (auto pDrawDocument = dynamic_cast<SdDrawDocument *>( &rBroadcaster ))
+            {
+                if (pDrawDocument->GetMasterSdPageCount(PageKind::Standard)
+                    == pDrawDocument->GetMasterSdPageCount(PageKind::Notes))
+                {
+                    AnalyzeUsedMasterPages (*pDrawDocument);
+                }
+            }
+            break;
+
+        default:
+            break;
+    }
+}
+
+void MasterPageObserver::Implementation::AnalyzeUsedMasterPages (
+    SdDrawDocument& rDocument)
+{
+    // Create a set of names of the master pages used by the given document.
+    sal_uInt16 nMasterPageCount = rDocument.GetMasterSdPageCount(PageKind::Standard);
+    ::std::set<OUString> aCurrentMasterPages;
+    for (sal_uInt16 nIndex=0; nIndex<nMasterPageCount; nIndex++)
+    {
+        SdPage* pMasterPage = rDocument.GetMasterSdPage (nIndex, PageKind::Standard);
+        if (pMasterPage != nullptr)
+            aCurrentMasterPages.insert (pMasterPage->GetName());
+    }
+
+    std::vector<OUString> aNewMasterPages;
+    std::vector<OUString> aRemovedMasterPages;
+    MasterPageContainer::iterator aOldMasterPagesDescriptor (
+        maUsedMasterPages.find(&rDocument));
+    if (aOldMasterPagesDescriptor == maUsedMasterPages.end())
+        return;
+
+    // Send events about the newly used master pages.
+    ::std::set_difference (
+        aCurrentMasterPages.begin(),
+        aCurrentMasterPages.end(),
+        aOldMasterPagesDescriptor->second.begin(),
+        aOldMasterPagesDescriptor->second.end(),
+        std::back_inserter(aNewMasterPages));
+    for (const auto& aNewMasterPage : aNewMasterPages)
+    {
+        MasterPageObserverEvent aEvent (
+            MasterPageObserverEvent::ET_MASTER_PAGE_ADDED,
+            aNewMasterPage);
+        SendEvent (aEvent);
+    }
+
+    // Send events about master pages that are not used any longer.
+    ::std::set_difference (
+        aOldMasterPagesDescriptor->second.begin(),
+        aOldMasterPagesDescriptor->second.end(),
+        aCurrentMasterPages.begin(),
+        aCurrentMasterPages.end(),
+        std::back_inserter(aRemovedMasterPages));
+    for (const auto& aRemovedMasterPage : aRemovedMasterPages)
+    {
+        MasterPageObserverEvent aEvent (
+            MasterPageObserverEvent::ET_MASTER_PAGE_REMOVED,
+            aRemovedMasterPage);
+        SendEvent (aEvent);
+    }
+
+    // Store the new list of master pages.
+    aOldMasterPagesDescriptor->second = aCurrentMasterPages;
+}
+
+void MasterPageObserver::Implementation::SendEvent (
+    MasterPageObserverEvent& rEvent)
+{
+    for (const auto& aLink : maListeners)
+    {
+        aLink.Call(rEvent);
+    }
+}
+
+} // end of namespace sd
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPagesSelector.cxx b/sd/source/ui/sidebar/MasterPagesSelector.cxx
new file mode 100644
index 000000000..979726910
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPagesSelector.cxx
@@ -0,0 +1,620 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sal/config.h>
+
+#include <utility>
+
+#include "MasterPagesSelector.hxx"
+
+#include "MasterPageContainer.hxx"
+#include "DocumentHelper.hxx"
+#include <pres.hxx>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include <app.hrc>
+
+#include <DrawController.hxx>
+#include <SlideSorterViewShell.hxx>
+#include "PreviewValueSet.hxx"
+#include <ViewShellBase.hxx>
+#include <o3tl/safeint.hxx>
+#include <vcl/image.hxx>
+#include <sfx2/dispatch.hxx>
+#include <sfx2/viewfrm.hxx>
+#include <sfx2/sidebar/Theme.hxx>
+#include <memory>
+
+using namespace ::com::sun::star::text;
+
+namespace sd::sidebar {
+
+    /** menu entry that is executed as default action when the left mouse button is
+        clicked over a master page.
+    */
+constexpr OStringLiteral gsDefaultClickAction = "applyselect";
+
+MasterPagesSelector::MasterPagesSelector (
+    weld::Widget* pParent,
+    SdDrawDocument& rDocument,
+    ViewShellBase& rBase,
+    const std::shared_ptr<MasterPageContainer>& rpContainer,
+    const css::uno::Reference<css::ui::XSidebar>& rxSidebar,
+    const OUString& rUIFileName,
+    const OString& rValueSetName)
+    : PanelLayout( pParent, "MasterPagePanel", rUIFileName ),
+      mpContainer(rpContainer),
+      mxPreviewValueSet(new PreviewValueSet),
+      mxPreviewValueSetWin(new weld::CustomWeld(*m_xBuilder, rValueSetName, *mxPreviewValueSet)),
+      mrDocument(rDocument),
+      mrBase(rBase),
+      mxSidebar(rxSidebar)
+{
+    mxPreviewValueSet->SetSelectHdl (
+        LINK(this, MasterPagesSelector, ClickHandler));
+    mxPreviewValueSet->SetContextMenuHandler (
+        LINK(this, MasterPagesSelector, ContextMenuHandler));
+    mxPreviewValueSet->SetStyle(mxPreviewValueSet->GetStyle() | WB_NO_DIRECTSELECT);
+
+    if (mxPreviewValueSet->GetDrawingArea()->get_ref_device().GetDPIScaleFactor() > 1)
+        mpContainer->SetPreviewSize(MasterPageContainer::LARGE);
+
+    mxPreviewValueSet->SetPreviewSize(mpContainer->GetPreviewSizePixel());
+    mxPreviewValueSet->Show();
+
+    mxPreviewValueSet->SetColor(sfx2::sidebar::Theme::GetColor(sfx2::sidebar::Theme::Color_PanelBackground));
+
+    Link<MasterPageContainerChangeEvent&,void> aChangeListener (LINK(this,MasterPagesSelector,ContainerChangeListener));
+    mpContainer->AddChangeListener(aChangeListener);
+}
+
+MasterPagesSelector::~MasterPagesSelector()
+{
+    Clear();
+    UpdateLocks(ItemList());
+
+    Link<MasterPageContainerChangeEvent&,void> aChangeListener (LINK(this,MasterPagesSelector,ContainerChangeListener));
+    mpContainer->RemoveChangeListener(aChangeListener);
+    mpContainer.reset();
+    mxPreviewValueSetWin.reset();
+    mxPreviewValueSet.reset();
+}
+
+void MasterPagesSelector::LateInit()
+{
+}
+
+sal_Int32 MasterPagesSelector::GetPreferredHeight (sal_Int32 nWidth)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    return mxPreviewValueSet->GetPreferredHeight (nWidth);
+}
+
+void MasterPagesSelector::UpdateLocks (const ItemList& rItemList)
+{
+    ItemList aNewLockList;
+
+    // In here we first lock the master pages in the given list and then
+    // release the locks acquired in a previous call to this method.  When
+    // this were done the other way round the lock count of some master
+    // pages might drop temporarily to 0 and would lead to unnecessary
+    // deletion and re-creation of MasterPageDescriptor objects.
+
+    // Lock the master pages in the given list.
+    for (const auto& rItem : rItemList)
+    {
+        mpContainer->AcquireToken(rItem);
+        aNewLockList.push_back(rItem);
+    }
+
+    // Release the previously locked master pages.
+    for (const auto& rPage : maLockedMasterPages)
+        mpContainer->ReleaseToken(rPage);
+
+    maLockedMasterPages.swap(aNewLockList);
+}
+
+void MasterPagesSelector::Fill()
+{
+    ::std::unique_ptr<ItemList> pItemList (new ItemList);
+
+    Fill(*pItemList);
+
+    UpdateLocks(*pItemList);
+    UpdateItemList(std::move(pItemList));
+}
+
+OUString MasterPagesSelector::GetContextMenuUIFile() const
+{
+    return "modules/simpress/ui/mastermenu.ui";
+}
+
+IMPL_LINK_NOARG(MasterPagesSelector, ClickHandler, ValueSet*, void)
+{
+    // We use the framework to assign the clicked-on master page because we
+    // so use the same mechanism as the context menu does (where we do not
+    // have the option to call the assignment method directly.)
+    ExecuteCommand(gsDefaultClickAction);
+}
+
+IMPL_LINK(MasterPagesSelector, ContextMenuHandler, const Point*, pPos, void)
+{
+    if (pPos)
+    {
+        // Here we only prepare the display of the context menu: on right
+        // click the item under the mouse is selected.
+        mxPreviewValueSet->GrabFocus();
+        mxPreviewValueSet->ReleaseMouse();
+
+        sal_uInt16 nIndex = mxPreviewValueSet->GetItemId(*pPos);
+        if (nIndex > 0)
+            mxPreviewValueSet->SelectItem(nIndex);
+    }
+
+    // Now do the actual display of the context menu
+    ShowContextMenu(pPos);
+}
+
+void MasterPagesSelector::ShowContextMenu(const Point* pPos)
+{
+    // Use the currently selected item and show the popup menu in its
+    // center.
+    const sal_uInt16 nIndex = mxPreviewValueSet->GetSelectedItemId();
+    if (nIndex <= 0)
+        return;
+
+    // The position of the upper left corner of the context menu is
+    // taken either from the mouse position (when the command was sent
+    // as reaction to a right click) or in the center of the selected
+    // item (when the command was sent as reaction to Shift+F10.)
+    Point aPosition;
+    if (!pPos)
+    {
+        ::tools::Rectangle aBBox (mxPreviewValueSet->GetItemRect(nIndex));
+        aPosition = aBBox.Center();
+    }
+    else
+        aPosition = *pPos;
+
+    // Setup the menu.
+    weld::Widget* pParent = mxPreviewValueSet->GetDrawingArea();
+    std::unique_ptr<weld::Builder> xBuilder(Application::CreateBuilder(pParent, GetContextMenuUIFile()));
+    std::unique_ptr<weld::Menu> xMenu(xBuilder->weld_menu("menu"));
+    ProcessPopupMenu(*xMenu);
+    ::tools::Rectangle aRect(aPosition, Size(1,1));
+    // Show the menu.
+    ExecuteCommand(xMenu->popup_at_rect(pParent, aRect));
+}
+
+void MasterPagesSelector::ProcessPopupMenu(weld::Menu& rMenu)
+{
+    // Disable some entries.
+    if (mpContainer->GetPreviewSize() == MasterPageContainer::SMALL)
+        rMenu.set_sensitive("small", false);
+    else
+        rMenu.set_sensitive("large", false);
+}
+
+void MasterPagesSelector::ExecuteCommand(const OString &rIdent)
+{
+    if (rIdent == "applyall")
+    {
+        mrBase.SetBusyState (true);
+        AssignMasterPageToAllSlides (GetSelectedMasterPage());
+        mrBase.SetBusyState (false);
+    }
+    else if (rIdent == "applyselect")
+    {
+        mrBase.SetBusyState (true);
+        AssignMasterPageToSelectedSlides (GetSelectedMasterPage());
+        mrBase.SetBusyState (false);
+    }
+    else if (rIdent == "large")
+    {
+        mrBase.SetBusyState (true);
+        mpContainer->SetPreviewSize(MasterPageContainer::LARGE);
+        mrBase.SetBusyState (false);
+        if (mxSidebar.is())
+            mxSidebar->requestLayout();
+    }
+    else if (rIdent == "small")
+    {
+        mrBase.SetBusyState (true);
+        mpContainer->SetPreviewSize(MasterPageContainer::SMALL);
+        mrBase.SetBusyState (false);
+        if (mxSidebar.is())
+            mxSidebar->requestLayout();
+    }
+    else if (rIdent == "edit")
+    {
+        using namespace ::com::sun::star;
+        uno::Reference<drawing::XDrawPage> xSelectedMaster;
+        SdPage* pMasterPage = GetSelectedMasterPage();
+        assert(pMasterPage); //rhbz#902884
+        if (pMasterPage)
+            xSelectedMaster.set(pMasterPage->getUnoPage(), uno::UNO_QUERY);
+        SfxViewFrame* pViewFrame = mrBase.GetViewFrame();
+        if (pViewFrame != nullptr && xSelectedMaster.is())
+        {
+            SfxDispatcher* pDispatcher = pViewFrame->GetDispatcher();
+            if (pDispatcher != nullptr)
+            {
+                sal_uInt16 nIndex = mxPreviewValueSet->GetSelectedItemId();
+                pDispatcher->Execute(SID_MASTERPAGE, SfxCallMode::SYNCHRON);
+                mxPreviewValueSet->SelectItem (nIndex);
+                mrBase.GetDrawController().setCurrentPage(xSelectedMaster);
+            }
+        }
+    }
+}
+
+IMPL_LINK(MasterPagesSelector, ContainerChangeListener, MasterPageContainerChangeEvent&, rEvent, void)
+{
+    NotifyContainerChangeEvent(rEvent);
+}
+
+SdPage* MasterPagesSelector::GetSelectedMasterPage()
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    SdPage* pMasterPage = nullptr;
+    sal_uInt16 nIndex = mxPreviewValueSet->GetSelectedItemId();
+    UserData* pData = GetUserData(nIndex);
+    if (pData != nullptr)
+    {
+        pMasterPage = mpContainer->GetPageObjectForToken(pData->second, true);
+    }
+    return pMasterPage;
+}
+
+/** Assemble a list of all slides of the document and pass it to
+    AssignMasterPageToPageList().
+*/
+void MasterPagesSelector::AssignMasterPageToAllSlides (SdPage* pMasterPage)
+{
+    if (pMasterPage == nullptr)
+        return;
+
+    sal_uInt16 nPageCount = mrDocument.GetSdPageCount(PageKind::Standard);
+    if (nPageCount == 0)
+        return;
+
+    // Get a list of all pages.  As a little optimization we only
+    // include pages that do not already have the given master page
+    // assigned.
+    OUString sFullLayoutName(pMasterPage->GetLayoutName());
+    ::sd::slidesorter::SharedPageSelection pPageList =
+        std::make_shared<::sd::slidesorter::SlideSorterViewShell::PageSelection>();
+    for (sal_uInt16 nPageIndex=0; nPageIndex<nPageCount; nPageIndex++)
+    {
+        SdPage* pPage = mrDocument.GetSdPage (nPageIndex, PageKind::Standard);
+        if (pPage != nullptr && pPage->GetLayoutName() != sFullLayoutName)
+        {
+            pPageList->push_back (pPage);
+        }
+    }
+
+    AssignMasterPageToPageList(pMasterPage, pPageList);
+}
+
+/** Assemble a list of the currently selected slides (selected in a visible
+    slide sorter) and pass it to AssignMasterPageToPageList().
+*/
+void MasterPagesSelector::AssignMasterPageToSelectedSlides (
+    SdPage* pMasterPage)
+{
+    using namespace ::sd::slidesorter;
+    using namespace ::sd::slidesorter::controller;
+
+    if (pMasterPage == nullptr)
+        return;
+
+    // Find a visible slide sorter.
+    SlideSorterViewShell* pSlideSorter = SlideSorterViewShell::GetSlideSorter(mrBase);
+    if (pSlideSorter == nullptr)
+        return;
+
+    // Get a list of selected pages.
+    SharedPageSelection pPageSelection = pSlideSorter->GetPageSelection();
+    if (pPageSelection->empty())
+        return;
+
+    AssignMasterPageToPageList(pMasterPage, pPageSelection);
+
+    // Restore the previous selection.
+    pSlideSorter->SetPageSelection(pPageSelection);
+}
+
+void MasterPagesSelector::AssignMasterPageToPageList (
+    SdPage* pMasterPage,
+    const std::shared_ptr<std::vector<SdPage*>>& rPageList)
+{
+    DocumentHelper::AssignMasterPageToPageList(mrDocument, pMasterPage, rPageList);
+}
+
+void MasterPagesSelector::NotifyContainerChangeEvent (const MasterPageContainerChangeEvent& rEvent)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    switch (rEvent.meEventType)
+    {
+        case MasterPageContainerChangeEvent::EventType::SIZE_CHANGED:
+            mxPreviewValueSet->SetPreviewSize(mpContainer->GetPreviewSizePixel());
+            UpdateAllPreviews();
+            break;
+
+        case MasterPageContainerChangeEvent::EventType::PREVIEW_CHANGED:
+        {
+            int nIndex (GetIndexForToken(rEvent.maChildToken));
+            if (nIndex >= 0)
+            {
+                mxPreviewValueSet->SetItemImage (
+                    static_cast<sal_uInt16>(nIndex),
+                    mpContainer->GetPreviewForToken(rEvent.maChildToken));
+                mxPreviewValueSet->Invalidate(mxPreviewValueSet->GetItemRect(static_cast<sal_uInt16>(nIndex)));
+            }
+        }
+        break;
+
+        case MasterPageContainerChangeEvent::EventType::DATA_CHANGED:
+        {
+            InvalidateItem(rEvent.maChildToken);
+            Fill();
+        }
+        break;
+
+        case MasterPageContainerChangeEvent::EventType::CHILD_REMOVED:
+        {
+            int nIndex (GetIndexForToken(rEvent.maChildToken));
+            SetItem(nIndex, MasterPageContainer::NIL_TOKEN);
+            break;
+        }
+
+        default:
+            break;
+   }
+}
+
+MasterPagesSelector::UserData* MasterPagesSelector::GetUserData (int nIndex) const
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    if (nIndex>0 && o3tl::make_unsigned(nIndex)<=mxPreviewValueSet->GetItemCount())
+        return static_cast<UserData*>(mxPreviewValueSet->GetItemData(static_cast<sal_uInt16>(nIndex)));
+    else
+        return nullptr;
+}
+
+void MasterPagesSelector::SetUserData (int nIndex, std::unique_ptr<UserData> pData)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    delete GetUserData(nIndex);
+    mxPreviewValueSet->SetItemData(static_cast<sal_uInt16>(nIndex), pData.release());
+}
+
+void MasterPagesSelector::SetItem (
+    sal_uInt16 nIndex,
+    MasterPageContainer::Token aToken)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    RemoveTokenToIndexEntry(nIndex,aToken);
+
+    if (nIndex <= 0)
+        return;
+
+    if (aToken != MasterPageContainer::NIL_TOKEN)
+    {
+        Image aPreview (mpContainer->GetPreviewForToken(aToken));
+        MasterPageContainer::PreviewState eState (mpContainer->GetPreviewState(aToken));
+
+        if (aPreview.GetSizePixel().Width()>0)
+        {
+            if (mxPreviewValueSet->GetItemPos(nIndex) != VALUESET_ITEM_NOTFOUND)
+            {
+                mxPreviewValueSet->SetItemImage(nIndex,aPreview);
+                mxPreviewValueSet->SetItemText(nIndex, mpContainer->GetPageNameForToken(aToken));
+            }
+            else
+            {
+                mxPreviewValueSet->InsertItem (
+                    nIndex,
+                    aPreview,
+                    mpContainer->GetPageNameForToken(aToken),
+                    nIndex);
+            }
+            SetUserData(nIndex, std::make_unique<UserData>(nIndex,aToken));
+
+            AddTokenToIndexEntry(nIndex,aToken);
+        }
+
+        if (eState == MasterPageContainer::PS_CREATABLE)
+            mpContainer->RequestPreview(aToken);
+    }
+    else
+    {
+        mxPreviewValueSet->RemoveItem(nIndex);
+    }
+
+}
+
+void MasterPagesSelector::AddTokenToIndexEntry (
+    sal_uInt16 nIndex,
+    MasterPageContainer::Token aToken)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    maTokenToValueSetIndex[aToken] = nIndex;
+}
+
+void MasterPagesSelector::RemoveTokenToIndexEntry (
+    sal_uInt16 nIndex,
+    MasterPageContainer::Token aNewToken)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    UserData* pData = GetUserData(nIndex);
+    if (pData != nullptr)
+    {
+        // Get the token that the index pointed to previously.
+        MasterPageContainer::Token aOldToken (pData->second);
+
+        if (aNewToken != aOldToken
+            && nIndex == GetIndexForToken(aOldToken))
+        {
+            maTokenToValueSetIndex[aOldToken] = 0;
+        }
+    }
+}
+
+void MasterPagesSelector::InvalidatePreview (const SdPage* pPage)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    for (size_t nIndex=1; nIndex<=mxPreviewValueSet->GetItemCount(); nIndex++)
+    {
+        UserData* pData = GetUserData(nIndex);
+        if (pData != nullptr)
+        {
+            MasterPageContainer::Token aToken (pData->second);
+            if (pPage == mpContainer->GetPageObjectForToken(aToken,false))
+            {
+                mpContainer->InvalidatePreview(aToken);
+                mpContainer->RequestPreview(aToken);
+                break;
+            }
+        }
+    }
+}
+
+void MasterPagesSelector::UpdateAllPreviews()
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    for (size_t nIndex=1; nIndex<=mxPreviewValueSet->GetItemCount(); nIndex++)
+    {
+        UserData* pData = GetUserData(nIndex);
+        if (pData != nullptr)
+        {
+            MasterPageContainer::Token aToken (pData->second);
+            mxPreviewValueSet->SetItemImage(
+                nIndex,
+                mpContainer->GetPreviewForToken(aToken));
+            if (mpContainer->GetPreviewState(aToken) == MasterPageContainer::PS_CREATABLE)
+                mpContainer->RequestPreview(aToken);
+        }
+    }
+    mxPreviewValueSet->Rearrange();
+}
+
+void MasterPagesSelector::ClearPageSet()
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    for (size_t nIndex=1; nIndex<=mxPreviewValueSet->GetItemCount(); nIndex++)
+    {
+        UserData* pData = GetUserData(nIndex);
+        delete pData;
+    }
+    mxPreviewValueSet->Clear();
+}
+
+void MasterPagesSelector::SetHelpId( const OString& aId )
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    mxPreviewValueSet->SetHelpId( aId );
+}
+
+sal_Int32 MasterPagesSelector::GetIndexForToken (MasterPageContainer::Token aToken) const
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    TokenToValueSetIndex::const_iterator iIndex (maTokenToValueSetIndex.find(aToken));
+    if (iIndex != maTokenToValueSetIndex.end())
+        return iIndex->second;
+    else
+        return -1;
+}
+
+void MasterPagesSelector::Clear()
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    ClearPageSet();
+}
+
+void MasterPagesSelector::InvalidateItem (MasterPageContainer::Token aToken)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    auto iItem = std::find(maCurrentItemList.begin(), maCurrentItemList.end(), aToken);
+    if (iItem != maCurrentItemList.end())
+        *iItem = MasterPageContainer::NIL_TOKEN;
+}
+
+void MasterPagesSelector::UpdateItemList (::std::unique_ptr<ItemList> && pNewItemList)
+{
+    const ::osl::MutexGuard aGuard (maMutex);
+
+    ItemList::const_iterator iNewItem (pNewItemList->begin());
+    ItemList::const_iterator iCurrentItem (maCurrentItemList.begin());
+    ItemList::const_iterator iNewEnd (pNewItemList->end());
+    ItemList::const_iterator iCurrentEnd (maCurrentItemList.end());
+    sal_uInt16 nIndex (1);
+
+    // Update existing items.
+    for ( ; iNewItem!=iNewEnd && iCurrentItem!=iCurrentEnd; ++iNewItem, ++iCurrentItem,++nIndex)
+    {
+        if (*iNewItem != *iCurrentItem)
+        {
+            SetItem(nIndex,*iNewItem);
+        }
+    }
+
+    // Append new items.
+    for ( ; iNewItem!=iNewEnd; ++iNewItem,++nIndex)
+    {
+        SetItem(nIndex,*iNewItem);
+    }
+
+    // Remove trailing items.
+    for ( ; iCurrentItem!=iCurrentEnd; ++iCurrentItem,++nIndex)
+    {
+        SetItem(nIndex,MasterPageContainer::NIL_TOKEN);
+    }
+
+    maCurrentItemList.swap(*pNewItemList);
+
+    mxPreviewValueSet->Rearrange();
+    if (mxSidebar.is())
+        mxSidebar->requestLayout();
+}
+
+css::ui::LayoutSize MasterPagesSelector::GetHeightForWidth (const sal_Int32 nWidth)
+{
+    const sal_Int32 nHeight (GetPreferredHeight(nWidth));
+    return css::ui::LayoutSize(nHeight,nHeight,nHeight);
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/MasterPagesSelector.hxx b/sd/source/ui/sidebar/MasterPagesSelector.hxx
new file mode 100644
index 000000000..1b6932789
--- /dev/null
+++ b/sd/source/ui/sidebar/MasterPagesSelector.hxx
@@ -0,0 +1,180 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <map>
+#include <memory>
+#include "MasterPageContainer.hxx"
+#include "PreviewValueSet.hxx"
+#include <sfx2/sidebar/ILayoutableWindow.hxx>
+#include <sfx2/sidebar/PanelLayout.hxx>
+
+#include <osl/mutex.hxx>
+
+namespace com::sun::star::ui { class XSidebar; }
+class MouseEvent;
+class SdDrawDocument;
+class SdPage;
+
+namespace sd {
+class ViewShellBase;
+}
+
+namespace sd::sidebar {
+
+/** Base class of a menu that lets the user select from a list of
+    templates or designs that are loaded from files.
+*/
+class MasterPagesSelector : public PanelLayout
+                          , public sfx2::sidebar::ILayoutableWindow
+{
+public:
+    MasterPagesSelector (
+        weld::Widget* pParent,
+        SdDrawDocument& rDocument,
+        ViewShellBase& rBase,
+        const std::shared_ptr<MasterPageContainer>& rpContainer,
+        const css::uno::Reference<css::ui::XSidebar>& rxSidebar,
+        const OUString& rUIFileName,
+        const OString& rValueSetName);
+    virtual ~MasterPagesSelector() override;
+
+    virtual void LateInit();
+
+    sal_Int32 GetPreferredHeight (sal_Int32 nWidth);
+
+    /** Make the selector empty.  This method clear the value set from any
+        entries. Override this method to add functionality, especially to
+        destroy objects set as data items at the value set.
+    */
+    void ClearPageSet();
+
+    void SetHelpId( const OString& aId );
+
+    /** Mark the preview that belongs to the given index as not up-to-date
+        anymore with respect to page content or preview size.
+        The implementation of this method will either sunchronously or
+        asynchronously call UpdatePreview().
+        @param nIndex
+            Index into the value set control that is used for displaying the
+            previews.
+    */
+    void InvalidatePreview (const SdPage* pPage);
+
+    void UpdateAllPreviews();
+
+    void ShowContextMenu(const Point* pPos);
+
+    // ILayoutableWindow
+    virtual css::ui::LayoutSize GetHeightForWidth (const sal_Int32 nWidth) override;
+
+protected:
+    mutable ::osl::Mutex maMutex;
+    std::shared_ptr<MasterPageContainer> mpContainer;
+
+    std::unique_ptr<PreviewValueSet> mxPreviewValueSet;
+    std::unique_ptr<weld::CustomWeld> mxPreviewValueSetWin;
+
+    SdDrawDocument& mrDocument;
+    ViewShellBase& mrBase;
+
+    SdPage* GetSelectedMasterPage();
+
+    /** Assign the given master page to all slides of the document.
+        @param pMasterPage
+            The master page to assign to all slides.
+    */
+    void AssignMasterPageToAllSlides (SdPage* pMasterPage);
+
+    /** Assign the given master page to all slides that are selected in a
+        slide sorter that is displayed in the lef or center pane.  When both
+        panes display a slide sorter then the one in the center pane is
+        used.
+    */
+    void AssignMasterPageToSelectedSlides (SdPage* pMasterPage);
+
+    virtual void AssignMasterPageToPageList (
+        SdPage* pMasterPage,
+        const std::shared_ptr<std::vector<SdPage*>>& rPageList);
+
+    virtual void NotifyContainerChangeEvent (const MasterPageContainerChangeEvent& rEvent);
+
+    typedef ::std::pair<int, MasterPageContainer::Token> UserData;
+    UserData* GetUserData (int nIndex) const;
+    void SetUserData (int nIndex, std::unique_ptr<UserData> pData);
+
+    sal_Int32 GetIndexForToken (MasterPageContainer::Token aToken) const;
+    typedef ::std::vector<MasterPageContainer::Token> ItemList;
+    void UpdateItemList (::std::unique_ptr<ItemList> && pList);
+    void Clear();
+    /** Invalidate the specified item so that on the next Fill() this item
+        is updated.
+    */
+    void InvalidateItem (MasterPageContainer::Token aToken);
+
+    // For every item in the ValueSet we store its associated token.  This
+    // allows a faster access and easier change tracking.
+    ItemList maCurrentItemList;
+    typedef ::std::map<MasterPageContainer::Token,sal_Int32> TokenToValueSetIndex;
+    TokenToValueSetIndex maTokenToValueSetIndex;
+
+    ItemList maLockedMasterPages;
+    /** Lock master pages in the given list and release locks that were
+        previously acquired.
+    */
+    void UpdateLocks (const ItemList& rItemList);
+
+    void Fill();
+    virtual void Fill (ItemList& rItemList) = 0;
+
+    /** Give derived classes the opportunity to provide their own context
+        menu.  If they do then they probably have to provide their own
+        Execute() and GetState() methods as well.
+    */
+    virtual OUString GetContextMenuUIFile() const;
+
+    virtual void ProcessPopupMenu(weld::Menu& rMenu);
+    virtual void ExecuteCommand(const OString& rIdent);
+
+private:
+    css::uno::Reference<css::ui::XSidebar> mxSidebar;
+
+    /** The offset between ValueSet index and MasterPageContainer::Token
+        last seen.  This value is used heuristically to speed up the lookup
+        of an index for a token.
+    */
+    DECL_LINK(ClickHandler, ValueSet*, void);
+    DECL_LINK(ContextMenuHandler, const Point*, void);
+    DECL_LINK(ContainerChangeListener, MasterPageContainerChangeEvent&, void);
+
+    void SetItem (
+        sal_uInt16 nIndex,
+        MasterPageContainer::Token aToken);
+    void AddTokenToIndexEntry (
+        sal_uInt16 nIndex,
+        MasterPageContainer::Token aToken);
+    void RemoveTokenToIndexEntry (
+        sal_uInt16 nIndex,
+        MasterPageContainer::Token aToken);
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/NavigatorWrapper.cxx b/sd/source/ui/sidebar/NavigatorWrapper.cxx
new file mode 100644
index 000000000..95d4a66ae
--- /dev/null
+++ b/sd/source/ui/sidebar/NavigatorWrapper.cxx
@@ -0,0 +1,49 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "NavigatorWrapper.hxx"
+#include <ViewShellBase.hxx>
+#include <navigatr.hxx>
+
+namespace sd::sidebar {
+
+NavigatorWrapper::NavigatorWrapper (
+    weld::Widget* pParent,
+    sd::ViewShellBase& rViewShellBase,
+    SfxBindings* pBindings)
+    : SdNavigatorWin(pParent, pBindings, nullptr)
+    , mrViewShellBase(rViewShellBase)
+{
+    SetUpdateRequestFunctor(
+            [this] () { return this->UpdateNavigator(); });
+}
+
+css::ui::LayoutSize NavigatorWrapper::GetHeightForWidth (const sal_Int32)
+{
+    return css::ui::LayoutSize(-1,-1,-1);
+}
+
+void NavigatorWrapper::UpdateNavigator()
+{
+    InitTreeLB(mrViewShellBase.GetDocument());
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/NavigatorWrapper.hxx b/sd/source/ui/sidebar/NavigatorWrapper.hxx
new file mode 100644
index 000000000..6632d796f
--- /dev/null
+++ b/sd/source/ui/sidebar/NavigatorWrapper.hxx
@@ -0,0 +1,57 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#pragma once
+
+#include <sfx2/sidebar/ILayoutableWindow.hxx>
+#include <navigatr.hxx>
+
+class SfxBindings;
+namespace sd { class ViewShellBase; }
+
+namespace sd::sidebar {
+
+/** Present the navigator as control that can be displayed inside the
+    sidebar.
+    This wrapper has two main responsibilities:
+    - Watch for document changes and update the navigator when one
+    happens.
+    - Forward size changes from sidebar to navigator.
+*/
+class NavigatorWrapper
+    : public SdNavigatorWin,
+      public sfx2::sidebar::ILayoutableWindow
+{
+public:
+    NavigatorWrapper (
+        weld::Widget* pParent,
+        sd::ViewShellBase& rViewShellBase,
+        SfxBindings* pBindings);
+
+    // From ILayoutableWindow
+    virtual css::ui::LayoutSize GetHeightForWidth (const sal_Int32 nWidth) override;
+
+private:
+    ViewShellBase& mrViewShellBase;
+
+    void UpdateNavigator();
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/PageMarginUtils.hxx b/sd/source/ui/sidebar/PageMarginUtils.hxx
new file mode 100644
index 000000000..9a1f83493
--- /dev/null
+++ b/sd/source/ui/sidebar/PageMarginUtils.hxx
@@ -0,0 +1,159 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#include <cmath>
+#include <tools/long.hxx>
+#define SDPAGE_NO_MARGIN       0
+#define SDPAGE_NARROW_VALUE    635
+#define SDPAGE_MODERATE_LR     955
+#define SDPAGE_NORMAL_VALUE    1000
+#define SDPAGE_WIDE_VALUE1     1270
+#define SDPAGE_WIDE_VALUE2     2540
+#define SDPAGE_WIDE_VALUE3     1590
+#define SDPAGE_UNIT_THRESHOLD  5
+
+namespace sd::sidebar{
+
+bool IsNone( const ::tools::Long nPageLeftMargin, const ::tools::Long nPageRightMargin,
+               const ::tools::Long nPageTopMargin, const ::tools::Long nPageBottomMargin )
+{
+    return( std::abs(nPageLeftMargin - SDPAGE_NO_MARGIN) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageRightMargin - SDPAGE_NO_MARGIN ) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageTopMargin - SDPAGE_NO_MARGIN) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageBottomMargin - SDPAGE_NO_MARGIN) <= SDPAGE_UNIT_THRESHOLD );
+}
+
+void SetNone( ::tools::Long& nPageLeftMargin, ::tools::Long& nPageRightMargin,
+                ::tools::Long& nPageTopMargin, ::tools::Long& nPageBottomMargin )
+{
+    nPageLeftMargin = SDPAGE_NO_MARGIN;
+    nPageRightMargin = SDPAGE_NO_MARGIN;
+    nPageTopMargin = SDPAGE_NO_MARGIN;
+    nPageBottomMargin = SDPAGE_NO_MARGIN;
+}
+
+bool IsNarrow( const ::tools::Long nPageLeftMargin, const ::tools::Long nPageRightMargin,
+               const ::tools::Long nPageTopMargin, const ::tools::Long nPageBottomMargin )
+{
+    return( std::abs(nPageLeftMargin - SDPAGE_NARROW_VALUE) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageRightMargin - SDPAGE_NARROW_VALUE) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageTopMargin - SDPAGE_NARROW_VALUE) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageBottomMargin - SDPAGE_NARROW_VALUE) <= SDPAGE_UNIT_THRESHOLD );
+}
+
+void SetNarrow( ::tools::Long& nPageLeftMargin, ::tools::Long& nPageRightMargin,
+                ::tools::Long& nPageTopMargin, ::tools::Long& nPageBottomMargin )
+{
+    nPageLeftMargin = SDPAGE_NARROW_VALUE;
+    nPageRightMargin = SDPAGE_NARROW_VALUE;
+    nPageTopMargin = SDPAGE_NARROW_VALUE;
+    nPageBottomMargin = SDPAGE_NARROW_VALUE;
+}
+
+bool IsModerate( const ::tools::Long nPageLeftMargin, const ::tools::Long nPageRightMargin,
+               const ::tools::Long nPageTopMargin, const ::tools::Long nPageBottomMargin )
+{
+    return( std::abs(nPageLeftMargin - SDPAGE_MODERATE_LR) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageRightMargin - SDPAGE_MODERATE_LR) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageTopMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageBottomMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD );
+}
+
+void SetModerate( ::tools::Long& nPageLeftMargin, ::tools::Long& nPageRightMargin,
+                ::tools::Long& nPageTopMargin, ::tools::Long& nPageBottomMargin )
+{
+    nPageLeftMargin = SDPAGE_MODERATE_LR;
+    nPageRightMargin = SDPAGE_MODERATE_LR;
+    nPageTopMargin = SDPAGE_WIDE_VALUE1;
+    nPageBottomMargin = SDPAGE_WIDE_VALUE1;
+}
+
+bool IsNormal075( const ::tools::Long nPageLeftMargin, const ::tools::Long nPageRightMargin,
+               const ::tools::Long nPageTopMargin, const ::tools::Long nPageBottomMargin )
+{
+    return( std::abs(nPageLeftMargin - SDPAGE_NORMAL_VALUE) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageRightMargin - SDPAGE_NORMAL_VALUE) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageTopMargin - SDPAGE_NORMAL_VALUE) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageBottomMargin - SDPAGE_NORMAL_VALUE) <= SDPAGE_UNIT_THRESHOLD );
+}
+
+void SetNormal075( ::tools::Long& nPageLeftMargin, ::tools::Long& nPageRightMargin,
+                ::tools::Long& nPageTopMargin, ::tools::Long& nPageBottomMargin )
+{
+    nPageLeftMargin = SDPAGE_NORMAL_VALUE;
+    nPageRightMargin = SDPAGE_NORMAL_VALUE;
+    nPageTopMargin = SDPAGE_NORMAL_VALUE;
+    nPageBottomMargin = SDPAGE_NORMAL_VALUE;
+}
+
+bool IsNormal100( const ::tools::Long nPageLeftMargin, const ::tools::Long nPageRightMargin,
+               const ::tools::Long nPageTopMargin, const ::tools::Long nPageBottomMargin )
+{
+    return( std::abs(nPageLeftMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageRightMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageTopMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageBottomMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD );
+}
+
+void SetNormal100( ::tools::Long& nPageLeftMargin, ::tools::Long& nPageRightMargin,
+                ::tools::Long& nPageTopMargin, ::tools::Long& nPageBottomMargin )
+{
+    nPageLeftMargin = SDPAGE_WIDE_VALUE1;
+    nPageRightMargin = SDPAGE_WIDE_VALUE1;
+    nPageTopMargin = SDPAGE_WIDE_VALUE1;
+    nPageBottomMargin = SDPAGE_WIDE_VALUE1;
+}
+
+bool IsNormal125( const ::tools::Long nPageLeftMargin, const ::tools::Long nPageRightMargin,
+               const ::tools::Long nPageTopMargin, const ::tools::Long nPageBottomMargin )
+{
+    return( std::abs(nPageLeftMargin - SDPAGE_WIDE_VALUE3) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageRightMargin - SDPAGE_WIDE_VALUE3) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageTopMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageBottomMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD );
+}
+
+void SetNormal125( ::tools::Long& nPageLeftMargin, ::tools::Long& nPageRightMargin,
+                ::tools::Long& nPageTopMargin, ::tools::Long& nPageBottomMargin )
+{
+    nPageLeftMargin = SDPAGE_WIDE_VALUE3;
+    nPageRightMargin = SDPAGE_WIDE_VALUE3;
+    nPageTopMargin = SDPAGE_WIDE_VALUE1;
+    nPageBottomMargin = SDPAGE_WIDE_VALUE1;
+}
+
+bool IsWide( const ::tools::Long nPageLeftMargin, const ::tools::Long nPageRightMargin,
+               const ::tools::Long nPageTopMargin, const ::tools::Long nPageBottomMargin )
+{
+    return( std::abs(nPageLeftMargin - SDPAGE_WIDE_VALUE2) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageRightMargin - SDPAGE_WIDE_VALUE2) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageTopMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD &&
+        std::abs(nPageBottomMargin - SDPAGE_WIDE_VALUE1) <= SDPAGE_UNIT_THRESHOLD );
+}
+
+void SetWide( ::tools::Long& nPageLeftMargin, ::tools::Long& nPageRightMargin,
+                ::tools::Long& nPageTopMargin, ::tools::Long& nPageBottomMargin )
+{
+    nPageLeftMargin = SDPAGE_WIDE_VALUE2;
+    nPageRightMargin = SDPAGE_WIDE_VALUE2;
+    nPageTopMargin = SDPAGE_WIDE_VALUE1;
+    nPageBottomMargin = SDPAGE_WIDE_VALUE1;
+}
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/PanelFactory.cxx b/sd/source/ui/sidebar/PanelFactory.cxx
new file mode 100644
index 000000000..c7ca8c25c
--- /dev/null
+++ b/sd/source/ui/sidebar/PanelFactory.cxx
@@ -0,0 +1,141 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "PanelFactory.hxx"
+#include <framework/Pane.hxx>
+#include <ViewShellBase.hxx>
+#include <DrawController.hxx>
+#include "LayoutMenu.hxx"
+#include "CurrentMasterPagesSelector.hxx"
+#include "RecentMasterPagesSelector.hxx"
+#include "AllMasterPagesSelector.hxx"
+#include <CustomAnimationPane.hxx>
+#include "NavigatorWrapper.hxx"
+#include <SlideTransitionPane.hxx>
+#include <TableDesignPane.hxx>
+#include "SlideBackground.hxx"
+
+#include <sfx2/sidebar/SidebarPanelBase.hxx>
+#include <com/sun/star/uno/XComponentContext.hpp>
+#include <comphelper/namedvaluecollection.hxx>
+#include <comphelper/servicehelper.hxx>
+#include <vcl/weldutils.hxx>
+
+using namespace css;
+using namespace css::uno;
+using namespace ::sd::framework;
+
+namespace sd::sidebar {
+
+//----- PanelFactory --------------------------------------------------------
+
+PanelFactory::PanelFactory()
+{
+}
+
+PanelFactory::~PanelFactory()
+{
+}
+
+// XUIElementFactory
+
+Reference<ui::XUIElement> SAL_CALL PanelFactory::createUIElement (
+    const OUString& rsUIElementResourceURL,
+    const css::uno::Sequence<css::beans::PropertyValue>& rArguments)
+{
+    // Process arguments.
+    const ::comphelper::NamedValueCollection aArguments (rArguments);
+    Reference<frame::XFrame> xFrame (aArguments.getOrDefault("Frame", Reference<frame::XFrame>()));
+    Reference<awt::XWindow> xParentWindow (aArguments.getOrDefault("ParentWindow", Reference<awt::XWindow>()));
+    Reference<ui::XSidebar> xSidebar (aArguments.getOrDefault("Sidebar", Reference<ui::XSidebar>()));
+
+    // Throw exceptions when the arguments are not as expected.
+    weld::Widget* pParent(nullptr);
+    if (weld::TransportAsXWindow* pTunnel = dynamic_cast<weld::TransportAsXWindow*>(xParentWindow.get()))
+        pParent = pTunnel->getWidget();
+
+    if (!pParent)
+        throw RuntimeException(
+            "PanelFactory::createUIElement called without ParentWindow");
+    if ( ! xFrame.is())
+        throw RuntimeException(
+            "PanelFactory::createUIElement called without XFrame");
+
+    // Tunnel through the controller to obtain a ViewShellBase.
+    ViewShellBase* pBase = nullptr;
+    auto pController = comphelper::getFromUnoTunnel<sd::DrawController>(xFrame->getController());
+    if (pController != nullptr)
+        pBase = pController->GetViewShellBase();
+    if (pBase == nullptr)
+        throw RuntimeException("can not get ViewShellBase for frame");
+
+    // Get bindings from given arguments.
+    const sal_uInt64 nBindingsValue (aArguments.getOrDefault("SfxBindings", sal_uInt64(0)));
+    SfxBindings* pBindings = reinterpret_cast<SfxBindings*>(nBindingsValue);
+
+    // Create a framework view.
+    std::unique_ptr<PanelLayout> xControl;
+    css::ui::LayoutSize aLayoutSize (-1,-1,-1);
+
+    /** Note that these names have to be identical to (the tail of)
+        the entries in officecfg/registry/data/org/openoffice/Office/Impress.xcu
+        for the TaskPanelFactory.
+    */
+    if (rsUIElementResourceURL.endsWith("/CustomAnimations"))
+        xControl = std::make_unique<CustomAnimationPane>(pParent, *pBase);
+    else if (rsUIElementResourceURL.endsWith("/Layouts"))
+        xControl = std::make_unique<LayoutMenu>(pParent, *pBase, xSidebar);
+    else if (rsUIElementResourceURL.endsWith("/AllMasterPages"))
+        xControl = AllMasterPagesSelector::Create(pParent, *pBase, xSidebar);
+    else if (rsUIElementResourceURL.endsWith("/RecentMasterPages"))
+        xControl = RecentMasterPagesSelector::Create(pParent, *pBase, xSidebar);
+    else if (rsUIElementResourceURL.endsWith("/UsedMasterPages"))
+        xControl = CurrentMasterPagesSelector::Create(pParent, *pBase, xSidebar);
+    else if (rsUIElementResourceURL.endsWith("/SlideTransitions"))
+        xControl = std::make_unique<SlideTransitionPane>(pParent, *pBase);
+    else if (rsUIElementResourceURL.endsWith("/TableDesign"))
+        xControl = std::make_unique<TableDesignPane>(pParent, *pBase);
+    else if (rsUIElementResourceURL.endsWith("/NavigatorPanel"))
+        xControl = std::make_unique<NavigatorWrapper>(pParent, *pBase, pBindings);
+    else if (rsUIElementResourceURL.endsWith("/SlideBackgroundPanel"))
+        xControl = std::make_unique<SlideBackground>(pParent, *pBase, xFrame, pBindings);
+
+    if (!xControl)
+        throw lang::IllegalArgumentException();
+
+    // Create a wrapper around the control that implements the
+    // necessary UNO interfaces.
+    return sfx2::sidebar::SidebarPanelBase::Create(
+        rsUIElementResourceURL,
+        xFrame,
+        std::move(xControl),
+        aLayoutSize);
+}
+
+} // end of namespace sd::sidebar
+
+
+extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface*
+org_openoffice_comp_Draw_framework_PanelFactory_get_implementation(css::uno::XComponentContext* /*context*/,
+                                                                   css::uno::Sequence<css::uno::Any> const &)
+{
+    return cppu::acquire(new sd::sidebar::PanelFactory);
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/PanelFactory.hxx b/sd/source/ui/sidebar/PanelFactory.hxx
new file mode 100644
index 000000000..77fc17dbc
--- /dev/null
+++ b/sd/source/ui/sidebar/PanelFactory.hxx
@@ -0,0 +1,49 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#pragma once
+
+#include <comphelper/compbase.hxx>
+
+#include <com/sun/star/ui/XUIElementFactory.hpp>
+
+namespace sd::sidebar {
+
+typedef comphelper::WeakComponentImplHelper <
+    css::ui::XUIElementFactory
+    > PanelFactoryInterfaceBase;
+
+class PanelFactory final
+    : public PanelFactoryInterfaceBase
+{
+public:
+    explicit PanelFactory ();
+    virtual ~PanelFactory() override;
+    PanelFactory(const PanelFactory&) = delete;
+    PanelFactory& operator=(const PanelFactory&) = delete;
+
+    // XUIElementFactory
+
+    css::uno::Reference<css::ui::XUIElement> SAL_CALL createUIElement (
+        const OUString& rsResourceURL,
+        const css::uno::Sequence<css::beans::PropertyValue>& rArguments) override;
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/PreviewValueSet.cxx b/sd/source/ui/sidebar/PreviewValueSet.cxx
new file mode 100644
index 000000000..f752d60eb
--- /dev/null
+++ b/sd/source/ui/sidebar/PreviewValueSet.cxx
@@ -0,0 +1,127 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "PreviewValueSet.hxx"
+#include <vcl/commandevent.hxx>
+
+namespace sd::sidebar {
+
+const int gnBorderWidth(3);
+const int gnBorderHeight(3);
+
+PreviewValueSet::PreviewValueSet()
+    : ValueSet(nullptr)
+    , maPreviewSize(10,10)
+{
+    SetStyle (
+        GetStyle()
+        & ~(WB_ITEMBORDER)// | WB_MENUSTYLEVALUESET)
+        //        | WB_FLATVALUESET);
+        );
+}
+
+void PreviewValueSet::SetDrawingArea(weld::DrawingArea* pDrawingArea)
+{
+    ValueSet::SetDrawingArea(pDrawingArea);
+
+    SetColCount(2);
+    SetExtraSpacing (2);
+}
+
+PreviewValueSet::~PreviewValueSet()
+{
+}
+
+void PreviewValueSet::SetPreviewSize (const Size& rSize)
+{
+    maPreviewSize = rSize;
+}
+
+void PreviewValueSet::SetContextMenuHandler(const Link<const Point*, void>& rLink)
+{
+    maContextMenuHandler = rLink;
+}
+
+bool PreviewValueSet::Command(const CommandEvent& rEvent)
+{
+    if (rEvent.GetCommand() != CommandEventId::ContextMenu)
+        return ValueSet::Command(rEvent);
+    maContextMenuHandler.Call(rEvent.IsMouseEvent() ? &rEvent.GetMousePosPixel() : nullptr);
+    return true;
+}
+
+void PreviewValueSet::Resize()
+{
+    ValueSet::Resize();
+
+    Size aWindowSize (GetOutputSizePixel());
+    if (!aWindowSize.IsEmpty())
+    {
+        Rearrange();
+    }
+}
+
+void PreviewValueSet::Rearrange()
+{
+    sal_uInt16 nNewColumnCount (CalculateColumnCount (
+        GetOutputSizePixel().Width()));
+    sal_uInt16 nNewRowCount (CalculateRowCount (nNewColumnCount));
+
+    SetFormat();
+    SetColCount(nNewColumnCount);
+    SetLineCount(nNewRowCount);
+}
+
+sal_uInt16 PreviewValueSet::CalculateColumnCount (int nWidth) const
+{
+    int nColumnCount = 0;
+    if (nWidth > 0)
+    {
+        nColumnCount = nWidth / (maPreviewSize.Width() + 2*gnBorderWidth);
+        if (nColumnCount < 1)
+            nColumnCount = 1;
+    }
+    return static_cast<sal_uInt16>(nColumnCount);
+}
+
+sal_uInt16 PreviewValueSet::CalculateRowCount (sal_uInt16 nColumnCount) const
+{
+    int nRowCount = 0;
+    int nItemCount = GetItemCount();
+    if (nColumnCount > 0)
+    {
+        nRowCount = (nItemCount+nColumnCount-1) / nColumnCount;
+        if (nRowCount < 1)
+            nRowCount = 1;
+    }
+
+    return static_cast<sal_uInt16>(nRowCount);
+}
+
+sal_Int32 PreviewValueSet::GetPreferredHeight (sal_Int32 nWidth)
+{
+    int nRowCount (CalculateRowCount(CalculateColumnCount(nWidth)));
+    int nItemHeight (maPreviewSize.Height());
+
+    return nRowCount * (nItemHeight + 2*gnBorderHeight);
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/PreviewValueSet.hxx b/sd/source/ui/sidebar/PreviewValueSet.hxx
new file mode 100644
index 000000000..adab3c78a
--- /dev/null
+++ b/sd/source/ui/sidebar/PreviewValueSet.hxx
@@ -0,0 +1,59 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <svtools/valueset.hxx>
+
+namespace sd::sidebar
+{
+/** Adapt the svtools valueset to the needs of the master page controls.
+*/
+class PreviewValueSet : public ValueSet
+{
+public:
+    explicit PreviewValueSet();
+    virtual void SetDrawingArea(weld::DrawingArea* pDrawingArea) override;
+    virtual ~PreviewValueSet() override;
+
+    void SetContextMenuHandler(const Link<const Point*, void>& rLink);
+
+    virtual void Resize() override;
+    virtual bool Command(const CommandEvent& rEvent) override;
+
+    void SetPreviewSize(const Size& rSize);
+
+    sal_Int32 GetPreferredHeight(sal_Int32 nWidth);
+
+    /** Set the number of rows and columns according to the current number
+        of items.  Call this method when new items have been inserted.
+    */
+    void Rearrange();
+
+private:
+    Link<const Point*, void> maContextMenuHandler;
+    Size maPreviewSize;
+
+    sal_uInt16 CalculateColumnCount(int nWidth) const;
+    sal_uInt16 CalculateRowCount(sal_uInt16 nColumnCount) const;
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/RecentMasterPagesSelector.cxx b/sd/source/ui/sidebar/RecentMasterPagesSelector.cxx
new file mode 100644
index 000000000..6e5a46c73
--- /dev/null
+++ b/sd/source/ui/sidebar/RecentMasterPagesSelector.cxx
@@ -0,0 +1,138 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "RecentMasterPagesSelector.hxx"
+
+#include <ViewShellBase.hxx>
+#include "RecentlyUsedMasterPages.hxx"
+#include <MasterPageObserver.hxx>
+#include <sdpage.hxx>
+#include <drawdoc.hxx>
+#include <helpids.h>
+
+namespace sd::sidebar {
+
+std::unique_ptr<PanelLayout> RecentMasterPagesSelector::Create (
+    weld::Widget* pParent,
+    ViewShellBase& rViewShellBase,
+    const css::uno::Reference<css::ui::XSidebar>& rxSidebar)
+{
+    SdDrawDocument* pDocument = rViewShellBase.GetDocument();
+    if (pDocument == nullptr)
+        return nullptr;
+
+    auto pContainer = std::make_shared<MasterPageContainer>();
+
+    auto xSelector(std::make_unique<RecentMasterPagesSelector>(
+            pParent,
+            *pDocument,
+            rViewShellBase,
+            pContainer,
+            rxSidebar));
+    xSelector->LateInit();
+    xSelector->SetHelpId(HID_SD_TASK_PANE_PREVIEW_RECENT);
+
+    return xSelector;
+}
+
+RecentMasterPagesSelector::RecentMasterPagesSelector (
+    weld::Widget* pParent,
+    SdDrawDocument& rDocument,
+    ViewShellBase& rBase,
+    const std::shared_ptr<MasterPageContainer>& rpContainer,
+    const css::uno::Reference<css::ui::XSidebar>& rxSidebar)
+    : MasterPagesSelector (pParent, rDocument, rBase, rpContainer, rxSidebar, "modules/simpress/ui/masterpagepanelrecent.ui", "recentvalueset")
+{
+}
+
+RecentMasterPagesSelector::~RecentMasterPagesSelector()
+{
+    RecentlyUsedMasterPages::Instance().RemoveEventListener (
+        LINK(this,RecentMasterPagesSelector,MasterPageListListener));
+}
+
+void RecentMasterPagesSelector::LateInit()
+{
+    MasterPagesSelector::LateInit();
+
+    MasterPagesSelector::Fill();
+    RecentlyUsedMasterPages::Instance().AddEventListener (
+        LINK(this,RecentMasterPagesSelector,MasterPageListListener));
+}
+
+IMPL_LINK_NOARG(RecentMasterPagesSelector, MasterPageListListener, LinkParamNone*, void)
+{
+    MasterPagesSelector::Fill();
+}
+
+void RecentMasterPagesSelector::Fill (ItemList& rItemList)
+{
+    // Create a set of names of the master pages used by the document.
+    MasterPageObserver::MasterPageNameSet aCurrentNames;
+    sal_uInt16 nMasterPageCount = mrDocument.GetMasterSdPageCount(PageKind::Standard);
+    for (sal_uInt16 nIndex=0; nIndex<nMasterPageCount; nIndex++)
+    {
+        SdPage* pMasterPage = mrDocument.GetMasterSdPage (nIndex, PageKind::Standard);
+        if (pMasterPage != nullptr)
+            aCurrentNames.insert (pMasterPage->GetName());
+    }
+
+    // Insert the recently used master pages that are currently not used.
+    RecentlyUsedMasterPages& rInstance (RecentlyUsedMasterPages::Instance());
+    int nPageCount = rInstance.GetMasterPageCount();
+    for (int nIndex=0; nIndex<nPageCount; nIndex++)
+    {
+        // Add an entry when a) the page is already known to the
+        // MasterPageContainer, b) the style name is empty, i.e. it has not yet
+        // been loaded (and thus can not be in use) or otherwise c) the
+        // style name is not currently in use.
+        MasterPageContainer::Token aToken (rInstance.GetTokenForIndex(nIndex));
+        if (aToken != MasterPageContainer::NIL_TOKEN)
+        {
+            OUString sStyleName (mpContainer->GetStyleNameForToken(aToken));
+            if (sStyleName.isEmpty()
+                || aCurrentNames.find(sStyleName) == aCurrentNames.end())
+            {
+                rItemList.push_back(aToken);
+            }
+        }
+    }
+}
+
+void RecentMasterPagesSelector::AssignMasterPageToPageList (
+    SdPage* pMasterPage,
+    const std::shared_ptr<std::vector<SdPage*> >& rpPageList)
+{
+    sal_uInt16 nSelectedItemId = mxPreviewValueSet->GetSelectedItemId();
+
+    MasterPagesSelector::AssignMasterPageToPageList(pMasterPage, rpPageList);
+
+    // Restore the selection.
+    if (mxPreviewValueSet->GetItemCount() > 0)
+    {
+        if (mxPreviewValueSet->GetItemCount() >= nSelectedItemId)
+            mxPreviewValueSet->SelectItem(nSelectedItemId);
+        else
+            mxPreviewValueSet->SelectItem(mxPreviewValueSet->GetItemCount());
+    }
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/RecentMasterPagesSelector.hxx b/sd/source/ui/sidebar/RecentMasterPagesSelector.hxx
new file mode 100644
index 000000000..6dbc3a2aa
--- /dev/null
+++ b/sd/source/ui/sidebar/RecentMasterPagesSelector.hxx
@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include "MasterPagesSelector.hxx"
+
+namespace sd::sidebar {
+
+/** Show the recently used master pages (that are not currently used).
+*/
+class RecentMasterPagesSelector final
+    : public MasterPagesSelector
+{
+    friend class VclPtrInstance<RecentMasterPagesSelector>;
+public:
+    static std::unique_ptr<PanelLayout> Create (
+        weld::Widget* pParent,
+        ViewShellBase& rViewShellBase,
+        const css::uno::Reference<css::ui::XSidebar>& rxSidebar);
+
+    RecentMasterPagesSelector (
+        weld::Widget* pParent,
+        SdDrawDocument& rDocument,
+        ViewShellBase& rBase,
+        const std::shared_ptr<MasterPageContainer>& rpContainer,
+        const css::uno::Reference<css::ui::XSidebar>& rxSidebar);
+    virtual ~RecentMasterPagesSelector() override;
+
+private:
+    DECL_LINK(MasterPageListListener, LinkParamNone*, void);
+    virtual void Fill (ItemList& rItemList) override;
+
+    using sd::sidebar::MasterPagesSelector::Fill;
+
+    /** Forward this call to the base class but save and restore the
+        currently selected item.
+        Assign the given master page to the list of pages.
+        @param pMasterPage
+            This master page will usually be a member of the list of all
+            available master pages as provided by the MasterPageContainer.
+        @param rPageList
+            The pages to which to assign the master page.  These pages may
+            be slides or master pages themselves.
+    */
+    virtual void AssignMasterPageToPageList (
+        SdPage* pMasterPage,
+        const std::shared_ptr<std::vector<SdPage*> >& rpPageList) override;
+
+    virtual void LateInit() override;
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/RecentlyUsedMasterPages.cxx b/sd/source/ui/sidebar/RecentlyUsedMasterPages.cxx
new file mode 100644
index 000000000..268658823
--- /dev/null
+++ b/sd/source/ui/sidebar/RecentlyUsedMasterPages.cxx
@@ -0,0 +1,366 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "RecentlyUsedMasterPages.hxx"
+#include "MasterPageContainerProviders.hxx"
+#include <MasterPageObserver.hxx>
+#include "MasterPageDescriptor.hxx"
+#include <tools/ConfigurationAccess.hxx>
+
+#include <algorithm>
+#include <memory>
+#include <vector>
+
+#include <com/sun/star/container/XNameAccess.hpp>
+#include <com/sun/star/container/XNameContainer.hpp>
+#include <com/sun/star/lang/XSingleServiceFactory.hpp>
+#include <osl/doublecheckedlocking.h>
+#include <osl/getglobalmutex.hxx>
+
+using namespace ::std;
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+
+namespace {
+
+OUString GetPathToImpressConfigurationRoot()
+{
+    return "/org.openoffice.Office.Impress/";
+}
+OUString GetPathToSetNode()
+{
+    return "MultiPaneGUI/ToolPanel/RecentlyUsedMasterPages";
+}
+
+} // end of anonymous namespace
+
+namespace sd::sidebar {
+
+RecentlyUsedMasterPages* RecentlyUsedMasterPages::mpInstance = nullptr;
+
+RecentlyUsedMasterPages&  RecentlyUsedMasterPages::Instance()
+{
+    if (mpInstance == nullptr)
+    {
+        ::osl::GetGlobalMutex aMutexFunctor;
+        ::osl::MutexGuard aGuard (aMutexFunctor());
+        if (mpInstance == nullptr)
+        {
+            RecentlyUsedMasterPages* pInstance = new RecentlyUsedMasterPages();
+            pInstance->LateInit();
+            SdGlobalResourceContainer::Instance().AddResource (
+                ::std::unique_ptr<SdGlobalResource>(pInstance));
+            OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
+            mpInstance = pInstance;
+        }
+    }
+    else {
+        OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
+    }
+
+    return *mpInstance;
+}
+
+constexpr size_t gnMaxListSize(8);
+
+RecentlyUsedMasterPages::RecentlyUsedMasterPages()
+    : mpContainer(std::make_shared<MasterPageContainer>())
+{
+}
+
+RecentlyUsedMasterPages::~RecentlyUsedMasterPages()
+{
+    Link<MasterPageContainerChangeEvent&,void> aLink (LINK(this,RecentlyUsedMasterPages,MasterPageContainerChangeListener));
+    mpContainer->RemoveChangeListener(aLink);
+
+    MasterPageObserver::Instance().RemoveEventListener(
+        LINK(this,RecentlyUsedMasterPages,MasterPageChangeListener));
+}
+
+void RecentlyUsedMasterPages::LateInit()
+{
+    Link<MasterPageContainerChangeEvent&,void> aLink (LINK(this,RecentlyUsedMasterPages,MasterPageContainerChangeListener));
+    mpContainer->AddChangeListener(aLink);
+
+    LoadPersistentValues ();
+    MasterPageObserver::Instance().AddEventListener(
+        LINK(this,RecentlyUsedMasterPages,MasterPageChangeListener));
+}
+
+void RecentlyUsedMasterPages::LoadPersistentValues()
+{
+    try
+    {
+        tools::ConfigurationAccess aConfiguration (
+            GetPathToImpressConfigurationRoot(),
+            tools::ConfigurationAccess::READ_ONLY);
+        Reference<container::XNameAccess> xSet (
+            aConfiguration.GetConfigurationNode(GetPathToSetNode()),
+            UNO_QUERY);
+        if ( ! xSet.is())
+            return;
+
+        static const OUStringLiteral sURLMemberName(u"URL");
+        static const OUStringLiteral sNameMemberName(u"Name");
+        OUString sURL;
+        OUString sName;
+
+        // Read the names and URLs of the master pages.
+        const Sequence<OUString> aKeys (xSet->getElementNames());
+        mvMasterPages.clear();
+        mvMasterPages.reserve(aKeys.getLength());
+        for (const auto& rKey : aKeys)
+        {
+            Reference<container::XNameAccess> xSetItem (
+                xSet->getByName(rKey), UNO_QUERY);
+            if (xSetItem.is())
+            {
+                Any aURL (xSetItem->getByName(sURLMemberName));
+                Any aName (xSetItem->getByName(sNameMemberName));
+                aURL >>= sURL;
+                aName >>= sName;
+                SharedMasterPageDescriptor pDescriptor = std::make_shared<MasterPageDescriptor>(
+                    MasterPageContainer::TEMPLATE,
+                    -1,
+                    sURL,
+                    OUString(),
+                    sName,
+                    false,
+                    std::make_shared<TemplatePageObjectProvider>(sURL),
+                    std::make_shared<TemplatePreviewProvider>(sURL));
+                // For user supplied templates we use a different
+                // preview provider: The preview in the document shows
+                // not only shapes on the master page but also shapes on
+                // the foreground.  This is misleading and therefore
+                // these previews are discarded and created directly
+                // from the page objects.
+                if (pDescriptor->GetURLClassification() == MasterPageDescriptor::URLCLASS_USER)
+                    pDescriptor->mpPreviewProvider = std::make_shared<PagePreviewProvider>();
+                MasterPageContainer::Token aToken (mpContainer->PutMasterPage(pDescriptor));
+                mvMasterPages.emplace_back(aToken,sURL,sName);
+            }
+        }
+
+        ResolveList();
+    }
+    catch (Exception&)
+    {
+        // Ignore exception.
+    }
+}
+
+void RecentlyUsedMasterPages::SavePersistentValues()
+{
+    try
+    {
+        tools::ConfigurationAccess aConfiguration (
+            GetPathToImpressConfigurationRoot(),
+            tools::ConfigurationAccess::READ_WRITE);
+        Reference<container::XNameContainer> xSet (
+            aConfiguration.GetConfigurationNode(GetPathToSetNode()),
+            UNO_QUERY);
+        if ( ! xSet.is())
+            return;
+
+        // Clear the set.
+        const Sequence<OUString> aKeys (xSet->getElementNames());
+        for (const auto& rKey : aKeys)
+            xSet->removeByName (rKey);
+
+        // Fill it with the URLs of this object.
+        static const OUStringLiteral sURLMemberName(u"URL");
+        static const OUStringLiteral sNameMemberName(u"Name");
+        Any aValue;
+        Reference<lang::XSingleServiceFactory> xChildFactory (
+            xSet, UNO_QUERY);
+        if ( ! xChildFactory.is())
+            return;
+        sal_Int32 nIndex(0);
+        for (const auto& rDescriptor : mvMasterPages)
+        {
+            // Create new child.
+            OUString sKey = "index_" + OUString::number(nIndex);
+            Reference<container::XNameReplace> xChild(
+                xChildFactory->createInstance(), UNO_QUERY);
+            if (xChild.is())
+            {
+                xSet->insertByName (sKey, Any(xChild));
+
+                aValue <<= rDescriptor.msURL;
+                xChild->replaceByName (sURLMemberName, aValue);
+
+                aValue <<= rDescriptor.msName;
+                xChild->replaceByName (sNameMemberName, aValue);
+            }
+            ++nIndex;
+        }
+
+        // Write the data back to disk.
+        aConfiguration.CommitChanges();
+    }
+    catch (Exception&)
+    {
+        // Ignore exception.
+    }
+}
+
+void RecentlyUsedMasterPages::AddEventListener (const Link<LinkParamNone*,void>& rEventListener)
+{
+    if (::std::find (
+        maListeners.begin(),
+        maListeners.end(),
+        rEventListener) == maListeners.end())
+    {
+        maListeners.push_back (rEventListener);
+    }
+}
+
+void RecentlyUsedMasterPages::RemoveEventListener (const Link<LinkParamNone*,void>& rEventListener)
+{
+    maListeners.erase (
+        ::std::find (
+            maListeners.begin(),
+            maListeners.end(),
+            rEventListener));
+}
+
+int RecentlyUsedMasterPages::GetMasterPageCount() const
+{
+    return mvMasterPages.size();
+}
+
+MasterPageContainer::Token RecentlyUsedMasterPages::GetTokenForIndex (sal_uInt32 nIndex) const
+{
+    if(nIndex<mvMasterPages.size())
+        return mvMasterPages[nIndex].maToken;
+    else
+        return MasterPageContainer::NIL_TOKEN;
+}
+
+void RecentlyUsedMasterPages::SendEvent()
+{
+    for (const auto& aLink : maListeners)
+    {
+        aLink.Call(nullptr);
+    }
+}
+
+IMPL_LINK(RecentlyUsedMasterPages, MasterPageChangeListener,
+    MasterPageObserverEvent&, rEvent, void)
+{
+    switch (rEvent.meType)
+    {
+        case MasterPageObserverEvent::ET_MASTER_PAGE_ADDED:
+        case MasterPageObserverEvent::ET_MASTER_PAGE_EXISTS:
+            AddMasterPage(
+                mpContainer->GetTokenForStyleName(rEvent.mrMasterPageName));
+            break;
+
+        case MasterPageObserverEvent::ET_MASTER_PAGE_REMOVED:
+            // Do not change the list of recently master pages (the deleted
+            // page was recently used) but tell the listeners.  They may want
+            // to update their lists.
+            SendEvent();
+            break;
+    }
+}
+
+IMPL_LINK(RecentlyUsedMasterPages, MasterPageContainerChangeListener,
+    MasterPageContainerChangeEvent&, rEvent, void)
+{
+    switch (rEvent.meEventType)
+    {
+        case MasterPageContainerChangeEvent::EventType::CHILD_ADDED:
+        case MasterPageContainerChangeEvent::EventType::CHILD_REMOVED:
+        case MasterPageContainerChangeEvent::EventType::INDEX_CHANGED:
+            ResolveList();
+            break;
+
+        default:
+            // Ignored.
+            break;
+    }
+}
+
+void RecentlyUsedMasterPages::AddMasterPage (
+    MasterPageContainer::Token aToken)
+{
+    // For the page to be inserted the token has to be valid and the page
+    // has to have a valid URL.  This excludes master pages that do not come
+    // from template files.
+    if (aToken == MasterPageContainer::NIL_TOKEN
+        || mpContainer->GetURLForToken(aToken).isEmpty())
+        return;
+
+    MasterPageList::iterator aIterator (
+        ::std::find_if(mvMasterPages.begin(),mvMasterPages.end(),
+            Descriptor::TokenComparator(aToken)));
+    if (aIterator != mvMasterPages.end())
+    {
+        // When an entry for the given token already exists then remove
+        // it now and insert it later at the head of the list.
+        mvMasterPages.erase (aIterator);
+    }
+
+    mvMasterPages.insert(mvMasterPages.begin(),
+        Descriptor(
+            aToken,
+            mpContainer->GetURLForToken(aToken),
+            mpContainer->GetStyleNameForToken(aToken)));
+
+    // Shorten list to maximal size.
+    while (mvMasterPages.size() > gnMaxListSize)
+    {
+        mvMasterPages.pop_back ();
+    }
+
+    SavePersistentValues ();
+    SendEvent();
+}
+
+void RecentlyUsedMasterPages::ResolveList()
+{
+    bool bNotify (false);
+
+    for (auto& rDescriptor : mvMasterPages)
+    {
+        if (rDescriptor.maToken == MasterPageContainer::NIL_TOKEN)
+        {
+            MasterPageContainer::Token aToken (mpContainer->GetTokenForURL(rDescriptor.msURL));
+            rDescriptor.maToken = aToken;
+            if (aToken != MasterPageContainer::NIL_TOKEN)
+                bNotify = true;
+        }
+        else
+        {
+            if ( ! mpContainer->HasToken(rDescriptor.maToken))
+            {
+                rDescriptor.maToken = MasterPageContainer::NIL_TOKEN;
+                bNotify = true;
+            }
+        }
+    }
+
+    if (bNotify)
+        SendEvent();
+}
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/RecentlyUsedMasterPages.hxx b/sd/source/ui/sidebar/RecentlyUsedMasterPages.hxx
new file mode 100644
index 000000000..e95e66ccb
--- /dev/null
+++ b/sd/source/ui/sidebar/RecentlyUsedMasterPages.hxx
@@ -0,0 +1,125 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <tools/SdGlobalResourceContainer.hxx>
+#include <tools/link.hxx>
+#include <vector>
+
+#include "MasterPageContainer.hxx"
+
+namespace sd {
+class MasterPageObserverEvent;
+}
+
+namespace sd::sidebar {
+
+/** This singleton holds a list of the most recently used master pages.
+*/
+class RecentlyUsedMasterPages
+    : public SdGlobalResource
+{
+public:
+    /** Return the single instance of this class.
+    */
+    static RecentlyUsedMasterPages& Instance();
+
+    void AddEventListener (const Link<LinkParamNone*,void>& rEventListener);
+    void RemoveEventListener (const Link<LinkParamNone*,void>& rEventListener);
+
+    int GetMasterPageCount() const;
+    MasterPageContainer::Token GetTokenForIndex (sal_uInt32 nIndex) const;
+
+private:
+    class Descriptor
+    {
+    public:
+        OUString msURL;
+        OUString msName;
+        ::sd::sidebar::MasterPageContainer::Token maToken;
+        Descriptor (::sd::sidebar::MasterPageContainer::Token aToken,
+                    const OUString& rsURL, const OUString& rsName)
+            : msURL(rsURL),
+              msName(rsName),
+              maToken(aToken)
+        {}
+
+        class TokenComparator
+        {
+        public:
+            explicit TokenComparator(::sd::sidebar::MasterPageContainer::Token aToken)
+                : maToken(aToken) {}
+            bool operator () (const Descriptor& rDescriptor)
+            { return maToken==rDescriptor.maToken; }
+
+        private:
+            ::sd::sidebar::MasterPageContainer::Token maToken;
+        };
+    };
+
+    /** The single instance of this class.  It is created on demand when
+        Instance() is called for the first time.
+    */
+    static RecentlyUsedMasterPages* mpInstance;
+
+    ::std::vector<Link<LinkParamNone*,void>> maListeners;
+
+    typedef ::std::vector<Descriptor> MasterPageList;
+    MasterPageList mvMasterPages;
+    std::shared_ptr<MasterPageContainer> mpContainer;
+
+    RecentlyUsedMasterPages();
+    virtual ~RecentlyUsedMasterPages() override;
+
+    /** Call this method after a new object has been created.
+    */
+    void LateInit();
+
+    RecentlyUsedMasterPages (const RecentlyUsedMasterPages&) = delete;
+
+    RecentlyUsedMasterPages& operator= (const RecentlyUsedMasterPages&) = delete;
+
+    void SendEvent();
+    DECL_LINK(MasterPageChangeListener, MasterPageObserverEvent&, void);
+    DECL_LINK(MasterPageContainerChangeListener, MasterPageContainerChangeEvent&, void);
+
+    /** Add a descriptor for the specified master page to the end of the
+        list of most recently used master pages.  When the page is already a
+        member of that list the associated descriptor is moved to the end of
+        the list to make it the most recently used entry.
+    */
+    void AddMasterPage(MasterPageContainer::Token aToken);
+
+    /** Load the list of recently used master pages from the registry where
+        it was saved to make it persistent.
+    */
+    void LoadPersistentValues();
+
+    /** Save the list of recently used master pages to the registry to make
+        it persistent.
+    */
+    void SavePersistentValues();
+
+    void ResolveList();
+};
+
+} // end of namespace sd::sidebar
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/SlideBackground.cxx b/sd/source/ui/sidebar/SlideBackground.cxx
new file mode 100644
index 000000000..742275bab
--- /dev/null
+++ b/sd/source/ui/sidebar/SlideBackground.cxx
@@ -0,0 +1,1286 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <com/sun/star/ui/XDeck.hpp>
+#include <com/sun/star/ui/XPanel.hpp>
+#include <com/sun/star/frame/XController2.hpp>
+#include <SlideSorter.hxx>
+#include <SlideSorterViewShell.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include "SlideBackground.hxx"
+#include <sdresid.hxx>
+#include <ViewShellBase.hxx>
+#include <FrameView.hxx>
+#include <DrawDocShell.hxx>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include "PageMarginUtils.hxx"
+#include <strings.hrc>
+#include <pageformatpanel.hrc>
+#include <DrawViewShell.hxx>
+#include <svl/intitem.hxx>
+#include <svx/colorbox.hxx>
+#include <svx/dlgutil.hxx>
+#include <svx/drawitem.hxx>
+#include <svx/itemwin.hxx>
+#include <svx/pageitem.hxx>
+#include <app.hrc>
+#include <editeng/paperinf.hxx>
+#include <svx/xflgrit.hxx>
+#include <svx/rulritem.hxx>
+#include <svx/svxids.hrc>
+#include <svx/xfillit0.hxx>
+#include <svx/xflclit.hxx>
+#include <svx/xgrad.hxx>
+#include <svx/xbtmpit.hxx>
+#include <svx/xflhtit.hxx>
+#include <svx/svdpage.hxx>
+#include <sfx2/bindings.hxx>
+#include <sfx2/dispatch.hxx>
+#include <sfx2/sidebar/Panel.hxx>
+#include <EventMultiplexer.hxx>
+#include <unotools/localedatawrapper.hxx>
+#include <vcl/EnumContext.hxx>
+#include <vcl/svapp.hxx>
+
+#include <editeng/sizeitem.hxx>
+#include <comphelper/lok.hxx>
+#include <unomodel.hxx>
+#include <sfx2/lokhelper.hxx>
+
+using namespace ::com::sun::star;
+
+using ::com::sun::star::uno::Reference;
+
+namespace sd::sidebar {
+
+namespace {
+
+enum eFillStyle
+{
+    NONE,
+    SOLID,
+    GRADIENT,
+    HATCH,
+    BITMAP,
+    PATTERN
+};
+
+}
+
+SlideBackground::SlideBackground(
+    weld::Widget* pParent,
+    ViewShellBase& rBase,
+    const css::uno::Reference<css::frame::XFrame>& rxFrame,
+    SfxBindings* pBindings) :
+    PanelLayout( pParent, "SlideBackgroundPanel", "modules/simpress/ui/sidebarslidebackground.ui" ),
+    mrBase( rBase ),
+    mxPaperSizeBox(new SvxPaperSizeListBox(m_xBuilder->weld_combo_box("paperformat"))),
+    mxPaperOrientation(m_xBuilder->weld_combo_box("orientation")),
+    mxMasterSlide(m_xBuilder->weld_combo_box("masterslide")),
+    mxBackgroundLabel(m_xBuilder->weld_label("label3")),
+    mxFillStyle(m_xBuilder->weld_combo_box("fillstyle")),
+    mxFillLB(new ColorListBox(m_xBuilder->weld_menu_button("fillattr"), [this]{ return GetFrameWeld(); })),
+    mxFillAttr(m_xBuilder->weld_combo_box("fillattr1")),
+    mxFillGrad1(new ColorListBox(m_xBuilder->weld_menu_button("fillattr2"), [this]{ return GetFrameWeld(); })),
+    mxFillGrad2(new ColorListBox(m_xBuilder->weld_menu_button("fillattr3"), [this]{ return GetFrameWeld(); })),
+    mxInsertImage(m_xBuilder->weld_button("button2")),
+    mxDspMasterBackground(m_xBuilder->weld_check_button("displaymasterbackground")),
+    mxDspMasterObjects(m_xBuilder->weld_check_button("displaymasterobjects")),
+    mxCloseMaster(m_xBuilder->weld_button("closemasterslide")),
+    mxEditMaster(m_xBuilder->weld_button("masterslidebutton")),
+    mxMasterLabel(m_xBuilder->weld_label("masterlabel")),
+    mxMarginSelectBox(m_xBuilder->weld_combo_box("marginLB")),
+    mxCustomEntry(m_xBuilder->weld_label("customlabel")),
+    mxMarginLabel(m_xBuilder->weld_label("labelmargin")),
+    maPaperSizeController(SID_ATTR_PAGE_SIZE, *pBindings, *this),
+    maPaperOrientationController(SID_ATTR_PAGE, *pBindings, *this),
+    maPaperMarginLRController(SID_ATTR_PAGE_LRSPACE, *pBindings, *this),
+    maPaperMarginULController(SID_ATTR_PAGE_ULSPACE, *pBindings, *this),
+    maBckColorController(SID_ATTR_PAGE_COLOR, *pBindings, *this),
+    maBckGradientController(SID_ATTR_PAGE_GRADIENT, *pBindings, *this),
+    maBckHatchController(SID_ATTR_PAGE_HATCH, *pBindings, *this),
+    maBckBitmapController(SID_ATTR_PAGE_BITMAP, *pBindings, *this),
+    maBckFillStyleController(SID_ATTR_PAGE_FILLSTYLE, *pBindings, *this),
+    maBckImageController(SID_SELECT_BACKGROUND, *pBindings, *this),
+    maDspBckController(SID_DISPLAY_MASTER_BACKGROUND, *pBindings, *this),
+    maDspObjController(SID_DISPLAY_MASTER_OBJECTS, *pBindings, *this),
+    maMetricController(SID_ATTR_METRIC, *pBindings, *this),
+    maCloseMasterController(SID_CLOSE_MASTER_VIEW, *pBindings, *this),
+    mpPageItem( new SvxPageItem(SID_ATTR_PAGE) ),
+    mbSwitchModeToNormal(false),
+    mbSwitchModeToMaster(false),
+    mxFrame(rxFrame),
+    maDrawOtherContext(vcl::EnumContext::Application::Draw, vcl::EnumContext::Context::DrawPage),
+    maDrawMasterContext(vcl::EnumContext::Application::Draw, vcl::EnumContext::Context::MasterPage),
+    maImpressOtherContext(vcl::EnumContext::Application::Impress, vcl::EnumContext::Context::DrawPage),
+    maImpressMasterContext(vcl::EnumContext::Application::Impress, vcl::EnumContext::Context::MasterPage),
+    maImpressHandoutContext(vcl::EnumContext::Application::Impress, vcl::EnumContext::Context::HandoutPage),
+    maImpressNotesContext(vcl::EnumContext::Application::Impress, vcl::EnumContext::Context::NotesPage),
+    mbTitle(false),
+    mpPageLRMarginItem( new SvxLongLRSpaceItem( 0, 0, SID_ATTR_PAGE_LRSPACE ) ),
+    mpPageULMarginItem( new SvxLongULSpaceItem( 0, 0, SID_ATTR_PAGE_ULSPACE ) ),
+    m_nPageLeftMargin(0),
+    m_nPageRightMargin(0),
+    m_nPageTopMargin(0),
+    m_nPageBottomMargin(0),
+    meFUnit(GetModuleFieldUnit()),
+    mpBindings(pBindings)
+{
+    //let the listbox shrink to any size so the sidebar isn't forced to grow to
+    //the size of the longest master slide name in the document
+    mxMasterSlide->set_size_request(42, -1);
+
+    maCustomEntry = mxCustomEntry->get_label();
+
+    addListener();
+    Initialize();
+}
+
+bool SlideBackground::IsDraw()
+{
+    return ( maContext == maDrawMasterContext ||
+             maContext == maDrawOtherContext );
+}
+
+bool SlideBackground::IsImpress()
+{
+    return ( maContext == maImpressMasterContext ||
+             maContext == maImpressOtherContext ||
+             maContext == maImpressHandoutContext ||
+             maContext == maImpressNotesContext );
+}
+
+FieldUnit SlideBackground::GetCurrentUnit(SfxItemState eState, const SfxPoolItem* pState)
+{
+    FieldUnit eUnit;
+
+    if (pState && eState >= SfxItemState::DEFAULT)
+        eUnit = static_cast<FieldUnit>(static_cast<const SfxUInt16Item*>(pState)->GetValue());
+    else
+        eUnit = GetModuleFieldUnit();
+
+    return eUnit;
+}
+
+void SlideBackground::SetMarginsFieldUnit()
+{
+    auto nSelected = mxMarginSelectBox->get_active();
+    mxMarginSelectBox->clear();
+
+    const LocaleDataWrapper& rLocaleData = Application::GetSettings().GetLocaleDataWrapper();
+
+    if (IsInch(meFUnit))
+    {
+        OUString sSuffix = weld::MetricSpinButton::MetricToString(FieldUnit::INCH);
+        for (size_t i = 0; i < SAL_N_ELEMENTS(RID_PAGEFORMATPANEL_MARGINS_INCH); ++i)
+        {
+            OUString sMeasurement = rLocaleData.getNum(RID_PAGEFORMATPANEL_MARGINS_INCH[i].second, 2, true, false) + sSuffix;
+            mxMarginSelectBox->append_text(SdResId(RID_PAGEFORMATPANEL_MARGINS_INCH[i].first).replaceFirst("%1", sMeasurement));
+        }
+    }
+    else
+    {
+        OUString sSuffix = " " + weld::MetricSpinButton::MetricToString(FieldUnit::CM);
+        for (size_t i = 0; i < SAL_N_ELEMENTS(RID_PAGEFORMATPANEL_MARGINS_CM); ++i)
+        {
+            OUString sMeasurement = rLocaleData.getNum(RID_PAGEFORMATPANEL_MARGINS_CM[i].second, 2, true, false) + sSuffix;
+            mxMarginSelectBox->append_text(SdResId(RID_PAGEFORMATPANEL_MARGINS_CM[i].first).replaceFirst("%1", sMeasurement));
+        }
+    }
+
+    mxMarginSelectBox->set_active(nSelected);
+}
+
+void SlideBackground::Initialize()
+{
+    SvxFillTypeBox::Fill(*mxFillStyle);
+
+    SetMarginsFieldUnit();
+
+    mxPaperSizeBox->FillPaperSizeEntries( PaperSizeApp::Draw );
+    mxPaperSizeBox->connect_changed(LINK(this,SlideBackground,PaperSizeModifyHdl));
+    mxPaperOrientation->connect_changed(LINK(this,SlideBackground,PaperSizeModifyHdl));
+    mxEditMaster->connect_clicked(LINK(this, SlideBackground, EditMasterHdl));
+    mxCloseMaster->connect_clicked(LINK(this, SlideBackground, CloseMasterHdl));
+    mxInsertImage->connect_clicked(LINK(this, SlideBackground, SelectBgHdl));
+    meUnit = maPaperSizeController.GetCoreMetric();
+
+    mxMasterSlide->connect_changed(LINK(this, SlideBackground, AssignMasterPage));
+
+    mxFillStyle->connect_changed(LINK(this, SlideBackground, FillStyleModifyHdl));
+    mxFillLB->SetSelectHdl(LINK(this, SlideBackground, FillColorHdl));
+    mxFillGrad1->SetSelectHdl(LINK(this, SlideBackground, FillColorHdl));
+    mxFillGrad2->SetSelectHdl(LINK(this, SlideBackground, FillColorHdl));
+    mxFillAttr->connect_changed(LINK(this, SlideBackground, FillBackgroundHdl));
+
+    ViewShell* pMainViewShell = mrBase.GetMainViewShell().get();
+    if (pMainViewShell)
+    {
+        FrameView *pFrameView = pMainViewShell->GetFrameView();
+
+        if ( pFrameView->GetViewShEditMode() ==  EditMode::Page )
+        {
+            SdPage* mpPage = pMainViewShell->getCurrentPage();
+            populateMasterSlideDropdown();
+
+            OUString aLayoutName( mpPage->GetLayoutName() );
+            aLayoutName = aLayoutName.copy(0,aLayoutName.indexOf(SD_LT_SEPARATOR));
+            mxMasterSlide->set_active_text(aLayoutName);
+        }
+    }
+
+    mxFillStyle->set_active(static_cast< sal_Int32 >(NONE));
+
+    mxDspMasterBackground->connect_toggled(LINK(this, SlideBackground, DspBackground));
+    mxDspMasterObjects->connect_toggled(LINK(this, SlideBackground, DspObjects));
+
+    //margins
+    mxMarginSelectBox->connect_changed(LINK(this, SlideBackground, ModifyMarginHdl));
+
+    Update();
+    UpdateMarginBox();
+}
+
+void SlideBackground::DumpAsPropertyTree(::tools::JsonWriter& rJsonWriter)
+{
+    if (mxPaperSizeBox->get_active() == -1)
+    {
+        mpBindings->Update(SID_ATTR_PAGE_SIZE);
+    }
+
+    PanelLayout::DumpAsPropertyTree(rJsonWriter);
+}
+
+void SlideBackground::HandleContextChange(
+    const vcl::EnumContext& rContext)
+{
+    if (maContext == rContext)
+        return;
+    maContext = rContext;
+
+    if ( IsImpress() )
+    {
+        mxMasterLabel->set_label(SdResId(STR_MASTERSLIDE_LABEL));
+
+        // margin selector is only for Draw
+        mxMarginSelectBox->hide();
+        mxMarginLabel->hide();
+
+        if ( maContext == maImpressMasterContext )
+        {
+            mxCloseMaster->show();
+            mxEditMaster->hide();
+            mxMasterSlide->set_sensitive(false);
+            mxMasterSlide->clear();
+            mxDspMasterBackground->set_sensitive(false);
+            mxDspMasterObjects->set_sensitive(false);
+            mxFillStyle->hide();
+            mxBackgroundLabel->hide();
+            mxInsertImage->show();
+
+            mxFillLB->hide();
+            mxFillAttr->hide();
+            mxFillGrad1->hide();
+            mxFillGrad2->hide();
+        }
+        else if ( maContext == maImpressHandoutContext  || maContext == maImpressNotesContext )
+        {
+            mxCloseMaster->hide();
+            mxEditMaster->hide();
+            mxMasterSlide->set_sensitive(false);
+            mxMasterSlide->clear();
+            mxDspMasterBackground->set_sensitive(false);
+            mxDspMasterObjects->set_sensitive(false);
+            mxFillStyle->hide();
+            mxBackgroundLabel->hide();
+            mxInsertImage->hide();
+        }
+        else if (maContext == maImpressOtherContext)
+        {
+            mxCloseMaster->hide();
+            mxEditMaster->show();
+            mxMasterSlide->set_sensitive(true);
+            populateMasterSlideDropdown();
+            mxDspMasterBackground->set_sensitive(true);
+            mxDspMasterObjects->set_sensitive(true);
+            mxFillStyle->show();
+            mxBackgroundLabel->show();
+            mxInsertImage->show();
+        }
+
+        // Need to do a relayouting, otherwise the panel size is not updated after show / hide controls
+        if (m_pPanel)
+            m_pPanel->TriggerDeckLayouting();
+
+    }
+    else if ( IsDraw() )
+    {
+        mxMasterLabel->set_label(SdResId(STR_MASTERPAGE_LABEL));
+        mxDspMasterBackground->hide();
+        mxDspMasterObjects->hide();
+
+        if (maContext == maDrawOtherContext)
+        {
+            mxEditMaster->hide();
+            mxFillStyle->show();
+            mxBackgroundLabel->show();
+        }
+        else if (maContext == maDrawMasterContext)
+        {
+            mxFillStyle->hide();
+            mxBackgroundLabel->hide();
+        }
+    }
+
+    // The Insert Image button in the sidebar issues .uno:SelectBackground,
+    // which when invoked without arguments will open the file-open-dialog
+    // to prompt the user to select a file. This is useless in LOOL.
+    // Hide for now so the user will only be able to use the menu to insert
+    // background image, which prompts the user for file selection in the browser.
+    if (comphelper::LibreOfficeKit::isActive())
+        mxInsertImage->hide();
+}
+
+void SlideBackground::Update()
+{
+    eFillStyle nPos = static_cast<eFillStyle>(mxFillStyle->get_active());
+
+    if(maContext != maImpressOtherContext && maContext != maDrawOtherContext)
+        nPos = NONE;
+
+    SfxObjectShell* pSh = SfxObjectShell::Current();
+    if (!pSh)
+        return;
+
+    switch(nPos)
+    {
+        case NONE:
+        {
+            mxFillLB->hide();
+            mxFillAttr->hide();
+            mxFillGrad1->hide();
+            mxFillGrad2->hide();
+        }
+        break;
+        case SOLID:
+        {
+            mxFillAttr->hide();
+            mxFillGrad1->hide();
+            mxFillGrad2->hide();
+            mxFillLB->show();
+            const Color aColor = GetColorSetOrDefault();
+            mxFillLB->SelectEntry(aColor);
+        }
+        break;
+        case GRADIENT:
+        {
+            mxFillLB->hide();
+            mxFillAttr->hide();
+            mxFillGrad1->show();
+            mxFillGrad2->show();
+
+            const XGradient xGradient = GetGradientSetOrDefault();
+            const Color aStartColor = xGradient.GetStartColor();
+            mxFillGrad1->SelectEntry(aStartColor);
+            const Color aEndColor = xGradient.GetEndColor();
+            mxFillGrad2->SelectEntry(aEndColor);
+        }
+        break;
+
+        case HATCH:
+        {
+            mxFillLB->hide();
+            mxFillAttr->show();
+            mxFillAttr->clear();
+            SvxFillAttrBox::Fill(*mxFillAttr, pSh->GetItem(SID_HATCH_LIST)->GetHatchList());
+            mxFillGrad1->hide();
+            mxFillGrad2->hide();
+
+            const OUString aHatchName = GetHatchingSetOrDefault();
+            mxFillAttr->set_active_text( aHatchName );
+        }
+        break;
+
+        case BITMAP:
+        case PATTERN:
+        {
+            mxFillLB->hide();
+            mxFillAttr->show();
+            mxFillAttr->clear();
+            mxFillGrad1->hide();
+            mxFillGrad2->hide();
+            OUString aName;
+            if(nPos == BITMAP)
+            {
+                SvxFillAttrBox::Fill(*mxFillAttr, pSh->GetItem(SID_BITMAP_LIST)->GetBitmapList());
+                aName = GetBitmapSetOrDefault();
+            }
+            else if(nPos == PATTERN)
+            {
+                SvxFillAttrBox::Fill(*mxFillAttr, pSh->GetItem(SID_PATTERN_LIST)->GetPatternList());
+                aName = GetPatternSetOrDefault();
+            }
+            mxFillAttr->set_active_text( aName );
+        }
+        break;
+        default:
+            break;
+    }
+
+    // Need to do a relayouting, otherwise the panel size is not updated after show / hide controls
+    if (m_pPanel)
+        m_pPanel->TriggerDeckLayouting();
+}
+
+void SlideBackground::UpdateMarginBox()
+{
+    m_nPageLeftMargin = mpPageLRMarginItem->GetLeft();
+    m_nPageRightMargin = mpPageLRMarginItem->GetRight();
+    m_nPageTopMargin = mpPageULMarginItem->GetUpper();
+    m_nPageBottomMargin = mpPageULMarginItem->GetLower();
+
+    int nCustomIndex = mxMarginSelectBox->find_text(maCustomEntry);
+
+    if( IsNone(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin) )
+    {
+        mxMarginSelectBox->set_active(0);
+        if (nCustomIndex != -1)
+            mxMarginSelectBox->remove(nCustomIndex);
+    }
+    else if( IsNarrow(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin) )
+    {
+        mxMarginSelectBox->set_active(1);
+        if (nCustomIndex != -1)
+            mxMarginSelectBox->remove(nCustomIndex);
+    }
+    else if( IsModerate(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin) )
+    {
+        mxMarginSelectBox->set_active(2);
+        if (nCustomIndex != -1)
+            mxMarginSelectBox->remove(nCustomIndex);
+    }
+    else if( IsNormal075(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin) )
+    {
+        mxMarginSelectBox->set_active(3);
+        if (nCustomIndex != -1)
+            mxMarginSelectBox->remove(nCustomIndex);
+    }
+    else if( IsNormal100(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin) )
+    {
+        mxMarginSelectBox->set_active(4);
+        if (nCustomIndex != -1)
+            mxMarginSelectBox->remove(nCustomIndex);
+    }
+    else if( IsNormal125(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin) )
+    {
+        mxMarginSelectBox->set_active(5);
+        if (nCustomIndex != -1)
+            mxMarginSelectBox->remove(nCustomIndex);
+    }
+    else if( IsWide(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin) )
+    {
+        mxMarginSelectBox->set_active(6);
+        if (nCustomIndex != -1)
+            mxMarginSelectBox->remove(nCustomIndex);
+    }
+    else
+    {
+        if (nCustomIndex == -1)
+            mxMarginSelectBox->append_text(maCustomEntry);
+        mxMarginSelectBox->set_active_text(maCustomEntry);
+    }
+}
+
+void SlideBackground::SetPanelTitle( const OUString& rTitle )
+{
+    Reference<frame::XController2> xController( mxFrame->getController(), uno::UNO_QUERY);
+    if ( !xController.is() )
+        return;
+
+    Reference<ui::XSidebarProvider> xSidebarProvider = xController->getSidebar();
+    if ( !xSidebarProvider.is() )
+        return;
+
+    Reference<ui::XDecks> xDecks = xSidebarProvider->getDecks();
+    if ( !xDecks.is() )
+        return;
+
+    Reference<ui::XDeck> xDeck ( xDecks->getByName("PropertyDeck"), uno::UNO_QUERY);
+    if ( !xDeck.is() )
+        return;
+
+    Reference<ui::XPanels> xPanels = xDeck->getPanels();
+    if ( !xPanels.is() )
+        return;
+
+    if (xPanels->hasByName("SlideBackgroundPanel"))
+    {
+        Reference<ui::XPanel> xPanel ( xPanels->getByName("SlideBackgroundPanel"), uno::UNO_QUERY);
+        if ( !xPanel.is() )
+            return;
+
+        xPanel->setTitle( rTitle );
+    }
+}
+
+void SlideBackground::addListener()
+{
+    Link<tools::EventMultiplexerEvent&,void> aLink( LINK(this, SlideBackground, EventMultiplexerListener) );
+    mrBase.GetEventMultiplexer()->AddEventListener( aLink );
+}
+
+void SlideBackground::removeListener()
+{
+    Link<tools::EventMultiplexerEvent&,void> aLink( LINK(this, SlideBackground, EventMultiplexerListener) );
+    mrBase.GetEventMultiplexer()->RemoveEventListener( aLink );
+}
+
+IMPL_LINK(SlideBackground, EventMultiplexerListener,
+                tools::EventMultiplexerEvent&, rEvent, void)
+{
+    switch (rEvent.meEventId)
+    {
+        // add more events as per requirement
+        // Master Page change triggers a shape change event. Solves sync problem.
+        case EventMultiplexerEventId::ShapeChanged:
+            populateMasterSlideDropdown();
+            break;
+        case EventMultiplexerEventId::EditModeNormal:
+            mbSwitchModeToNormal = true;
+            break;
+        case EventMultiplexerEventId::EditModeMaster:
+            mbSwitchModeToMaster = true;
+            break;
+        case EventMultiplexerEventId::EditViewSelection:
+        case EventMultiplexerEventId::EndTextEdit:
+        {
+            if ( mbSwitchModeToMaster )
+            {
+                if( IsImpress() )
+                    SetPanelTitle(SdResId(STR_MASTERSLIDE_NAME));
+                else
+                    SetPanelTitle(SdResId(STR_MASTERPAGE_NAME));
+                mbSwitchModeToMaster = false;
+            }
+            else if ( mbSwitchModeToNormal )
+            {
+                if( IsImpress() )
+                    SetPanelTitle(SdResId(STR_SLIDE_NAME));
+                else
+                    SetPanelTitle(SdResId(STR_PAGE_NAME));
+                mbSwitchModeToNormal = false;
+            }
+
+        }
+        break;
+        case EventMultiplexerEventId::CurrentPageChanged:
+        {
+            static const sal_uInt16 SidArray[] = {
+                SID_ATTR_PAGE_COLOR,
+                SID_ATTR_PAGE_GRADIENT,
+                SID_ATTR_PAGE_HATCH,
+                SID_ATTR_PAGE_BITMAP,
+                SID_ATTR_PAGE_FILLSTYLE,
+                SID_DISPLAY_MASTER_BACKGROUND,
+                SID_DISPLAY_MASTER_OBJECTS,
+                0 };
+            updateMasterSlideSelection();
+            GetBindings()->Invalidate( SidArray );
+        }
+        break;
+        case EventMultiplexerEventId::ViewAdded:
+        {
+            if(!mbTitle)
+            {
+                if( IsDraw() )
+                {
+                    mxCloseMaster->hide();
+                    mxEditMaster->hide();
+                    if( maContext == maDrawMasterContext)
+                        SetPanelTitle(SdResId(STR_MASTERPAGE_NAME));
+                    else
+                        SetPanelTitle(SdResId(STR_PAGE_NAME));
+                }
+                else if ( maContext == maImpressOtherContext || maContext == maImpressMasterContext )
+                {
+                    if( maContext == maImpressMasterContext )
+                        SetPanelTitle(SdResId(STR_MASTERSLIDE_NAME));
+                    else
+                        SetPanelTitle(SdResId(STR_SLIDE_NAME));
+                }
+                else if ( maContext == maImpressNotesContext )
+                {
+                    mxMasterLabel->set_label(SdResId(STR_MASTERSLIDE_LABEL));
+                    ViewShell* pMainViewShell = mrBase.GetMainViewShell().get();
+
+                    if (pMainViewShell)
+                    {
+                        DrawViewShell* pDrawViewShell = static_cast<DrawViewShell*>(pMainViewShell);
+                        if ( pDrawViewShell->GetEditMode() == EditMode::MasterPage)
+                            SetPanelTitle(SdResId(STR_MASTERSLIDE_NAME));
+                        else // EditMode::Page
+                            SetPanelTitle(SdResId(STR_SLIDE_NAME));
+                    }
+                }
+                mbTitle = true;
+            }
+        }
+        break;
+        default:
+            break;
+    }
+}
+
+void SlideBackground::populateMasterSlideDropdown()
+{
+    mxMasterSlide->clear();
+    ::sd::DrawDocShell* pDocSh = dynamic_cast<::sd::DrawDocShell*>( SfxObjectShell::Current() );
+    SdDrawDocument* pDoc = pDocSh ? pDocSh->GetDoc() : nullptr;
+    sal_uInt16 nCount = pDoc ? pDoc->GetMasterPageCount() : 0;
+    for( sal_uInt16 nLayout = 0; nLayout < nCount; nLayout++ )
+    {
+        SdPage* pMaster = static_cast<SdPage*>(pDoc->GetMasterPage(nLayout));
+        if( pMaster->GetPageKind() == PageKind::Standard)
+        {
+            OUString aLayoutName(pMaster->GetLayoutName());
+            aLayoutName = aLayoutName.copy(0,aLayoutName.indexOf(SD_LT_SEPARATOR));
+            mxMasterSlide->append_text(aLayoutName);
+        }
+    }
+    updateMasterSlideSelection();
+}
+
+void SlideBackground::updateMasterSlideSelection()
+{
+    ViewShell* pMainViewShell = mrBase.GetMainViewShell().get();
+    SdPage* pPage = pMainViewShell ? pMainViewShell->getCurrentPage() : nullptr;
+    if (pPage != nullptr && pPage->TRG_HasMasterPage())
+    {
+        SdrPage& rMasterPage (pPage->TRG_GetMasterPage());
+        SdPage* pMasterPage = static_cast<SdPage*>(&rMasterPage);
+        mxMasterSlide->set_active_text(pMasterPage->GetName());
+    }
+}
+
+SlideBackground::~SlideBackground()
+{
+    removeListener();
+
+    mxCustomEntry.reset();
+    mxMarginLabel.reset();
+    mxPaperSizeBox.reset();
+    mxPaperOrientation.reset();
+    mxMasterSlide.reset();
+    mxBackgroundLabel.reset();
+    mxFillAttr.reset();
+    mxFillGrad1.reset();
+    mxFillGrad2.reset();
+    mxFillStyle.reset();
+    mxFillLB.reset();
+    mxInsertImage.reset();
+    mxMarginSelectBox.reset();
+    mxDspMasterBackground.reset();
+    mxDspMasterObjects.reset();
+    mxMasterLabel.reset();
+    mxEditMaster.reset();
+    mxCloseMaster.reset();
+
+    maPaperSizeController.dispose();
+    maPaperOrientationController.dispose();
+    maPaperMarginLRController.dispose();
+    maPaperMarginULController.dispose();
+    maBckColorController.dispose();
+    maBckGradientController.dispose();
+    maBckHatchController.dispose();
+    maBckBitmapController.dispose();
+    maBckFillStyleController.dispose();
+    maBckImageController.dispose();
+    maDspBckController.dispose();
+    maDspObjController.dispose();
+    maMetricController.dispose();
+    maCloseMasterController.dispose();
+
+    mpPageItem.reset();
+    mpColorItem.reset();
+    mpHatchItem.reset();
+    mpBitmapItem.reset();
+    mpPageLRMarginItem.reset();
+    mpPageULMarginItem.reset();
+}
+
+void SlideBackground::ExecuteMarginLRChange(const ::tools::Long mnPageLeftMargin, const ::tools::Long mnPageRightMargin)
+{
+    mpPageLRMarginItem->SetLeft(mnPageLeftMargin);
+    mpPageLRMarginItem->SetRight(mnPageRightMargin);
+    GetBindings()->GetDispatcher()->ExecuteList( SID_ATTR_PAGE_LRSPACE, SfxCallMode::RECORD, { mpPageLRMarginItem.get() } );
+}
+
+void SlideBackground::ExecuteMarginULChange(const ::tools::Long mnPageTopMargin, const ::tools::Long mnPageBottomMargin)
+{
+    mpPageULMarginItem->SetUpper(mnPageTopMargin);
+    mpPageULMarginItem->SetLower(mnPageBottomMargin);
+    GetBindings()->GetDispatcher()->ExecuteList( SID_ATTR_PAGE_ULSPACE, SfxCallMode::RECORD, { mpPageULMarginItem.get() } );
+}
+
+Color const & SlideBackground::GetColorSetOrDefault()
+{
+   // Tango Sky Blue 1, to be consistent w/ area fill panel (b/c COL_AUTO for slides is transparent)
+   if ( !mpColorItem )
+        mpColorItem.reset( new XFillColorItem( OUString(), Color(0x72, 0x9f, 0xcf) ) );
+
+   return mpColorItem->GetColorValue();
+}
+
+XGradient const & SlideBackground::GetGradientSetOrDefault()
+{
+    if( !mpGradientItem )
+    {
+        XGradient aGradient;
+        OUString aGradientName;
+        if (SfxObjectShell* pSh = SfxObjectShell::Current())
+        {
+            const SvxGradientListItem * pGradListItem = pSh->GetItem(SID_GRADIENT_LIST);
+            aGradient = pGradListItem->GetGradientList()->GetGradient(0)->GetGradient();
+            aGradientName = pGradListItem->GetGradientList()->GetGradient(0)->GetName();
+        }
+        mpGradientItem.reset( new XFillGradientItem( aGradientName, aGradient ) );
+    }
+
+    return mpGradientItem->GetGradientValue();
+}
+
+OUString const & SlideBackground::GetHatchingSetOrDefault()
+{
+    if( !mpHatchItem )
+    {
+        XHatch aHatch;
+        OUString aHatchName;
+        if (SfxObjectShell* pSh = SfxObjectShell::Current())
+        {
+            const SvxHatchListItem * pHatchListItem = pSh->GetItem(SID_HATCH_LIST);
+            aHatch = pHatchListItem->GetHatchList()->GetHatch(0)->GetHatch();
+            aHatchName = pHatchListItem->GetHatchList()->GetHatch(0)->GetName();
+        }
+        mpHatchItem.reset( new XFillHatchItem( aHatchName, aHatch ) );
+    }
+
+    return mpHatchItem->GetName();
+}
+
+OUString const & SlideBackground::GetBitmapSetOrDefault()
+{
+    if( !mpBitmapItem || mpBitmapItem->isPattern())
+    {
+        GraphicObject aGraphObj;
+        OUString aBmpName;
+        if (SfxObjectShell* pSh = SfxObjectShell::Current())
+        {
+            const SvxBitmapListItem * pBmpListItem = pSh->GetItem(SID_BITMAP_LIST);
+            aGraphObj = pBmpListItem->GetBitmapList()->GetBitmap(0)->GetGraphicObject();
+            aBmpName = pBmpListItem->GetBitmapList()->GetBitmap(0)->GetName();
+        }
+        mpBitmapItem.reset( new XFillBitmapItem( aBmpName, aGraphObj ) );
+    }
+
+    return mpBitmapItem->GetName();
+}
+
+OUString const & SlideBackground::GetPatternSetOrDefault()
+{
+    if( !mpBitmapItem || !(mpBitmapItem->isPattern()))
+    {
+        GraphicObject aGraphObj;
+        OUString aPtrnName;
+        if (SfxObjectShell* pSh = SfxObjectShell::Current())
+        {
+            const SvxPatternListItem * pPtrnListItem = pSh->GetItem(SID_PATTERN_LIST);
+            aGraphObj = pPtrnListItem->GetPatternList()->GetBitmap(0)->GetGraphicObject();
+            aPtrnName = pPtrnListItem->GetPatternList()->GetBitmap(0)->GetName();
+        }
+        mpBitmapItem.reset( new XFillBitmapItem( aPtrnName, aGraphObj ) );
+    }
+
+    return mpBitmapItem->GetName();
+}
+
+void SlideBackground::NotifyItemUpdate(
+    const sal_uInt16 nSID,
+    const SfxItemState eState,
+    const SfxPoolItem* pState)
+{
+    switch(nSID)
+    {
+
+        case SID_ATTR_PAGE_COLOR:
+        {
+            if(eState >= SfxItemState::DEFAULT)
+            {
+                mxFillStyle->set_active(static_cast< sal_Int32 >(SOLID));
+                mpColorItem.reset(pState ? static_cast< XFillColorItem* >(pState->Clone()) : nullptr);
+                Update();
+            }
+        }
+        break;
+
+        case SID_ATTR_PAGE_HATCH:
+        {
+            if(eState >= SfxItemState::DEFAULT)
+            {
+                mxFillStyle->set_active(static_cast< sal_Int32 >(HATCH));
+                mpHatchItem.reset(pState ? static_cast < XFillHatchItem* >(pState->Clone()) : nullptr);
+                Update();
+            }
+        }
+        break;
+
+        case SID_ATTR_PAGE_GRADIENT:
+        {
+            if(eState >= SfxItemState::DEFAULT)
+            {
+                mxFillStyle->set_active(static_cast< sal_Int32>(GRADIENT));
+                mpGradientItem.reset(pState ? static_cast< XFillGradientItem* >(pState->Clone()) : nullptr);
+                Update();
+            }
+        }
+        break;
+        case SID_ATTR_PAGE_BITMAP:
+        {
+            if(eState >= SfxItemState::DEFAULT)
+            {
+                mpBitmapItem.reset(pState ? static_cast< XFillBitmapItem* >(pState->Clone()) : nullptr);
+                if(mpBitmapItem)
+                {
+                    if(mpBitmapItem->isPattern())
+                        mxFillStyle->set_active(static_cast< sal_Int32 >(PATTERN));
+                    else
+                        mxFillStyle->set_active(static_cast< sal_Int32 >(BITMAP));
+                }
+                else
+                    mxFillStyle->set_active(static_cast< sal_Int32 >(BITMAP));
+                Update();
+            }
+        }
+        break;
+
+        case SID_ATTR_PAGE_FILLSTYLE:
+        {
+            const XFillStyleItem* pFillStyleItem = nullptr;
+            if (eState >= SfxItemState::DEFAULT)
+                pFillStyleItem = dynamic_cast< const XFillStyleItem* >(pState);
+            if (pFillStyleItem)
+            {
+                css::drawing::FillStyle eXFS = pFillStyleItem->GetValue();
+                switch(eXFS)
+                {
+                    case drawing::FillStyle_NONE:
+                        mxFillStyle->set_active(static_cast< sal_Int32 >(NONE));
+                        break;
+                    case drawing::FillStyle_SOLID:
+                        mxFillStyle->set_active(static_cast< sal_Int32 >(SOLID));
+                        break;
+                    case drawing::FillStyle_GRADIENT:
+                        mxFillStyle->set_active(static_cast< sal_Int32 >(GRADIENT));
+                        break;
+                    case drawing::FillStyle_HATCH:
+                        mxFillStyle->set_active(static_cast< sal_Int32 >(HATCH));
+                        break;
+                    case drawing::FillStyle_BITMAP:
+                    {
+                        if(mpBitmapItem->isPattern())
+                            mxFillStyle->set_active(static_cast< sal_Int32 >(PATTERN));
+                        else
+                            mxFillStyle->set_active(static_cast< sal_Int32 >(BITMAP));
+                    }
+                    break;
+                    default:
+                        break;
+                }
+                Update();
+            }
+        }
+        break;
+
+        case SID_ATTR_PAGE_SIZE:
+        {
+            const SvxSizeItem* pSizeItem = nullptr;
+            if (eState >= SfxItemState::DEFAULT)
+                pSizeItem = dynamic_cast<const SvxSizeItem*>(pState);
+            if (pSizeItem)
+            {
+                Size aPaperSize = pSizeItem->GetSize();
+                if (mxPaperOrientation->get_active() == 0)
+                   Swap(aPaperSize);
+
+                Paper ePaper = SvxPaperInfo::GetSvxPaper(aPaperSize, meUnit);
+                mxPaperSizeBox->set_active_id( ePaper );
+            }
+        }
+        break;
+
+        case SID_ATTR_PAGE:
+        {
+            const SvxPageItem* pPageItem = nullptr;
+            if (eState >= SfxItemState::DEFAULT)
+                pPageItem = dynamic_cast<const SvxPageItem*>(pState);
+            if (pPageItem)
+            {
+                mpPageItem.reset(pPageItem->Clone());
+                bool bIsLandscape = mpPageItem->IsLandscape();
+                mxPaperOrientation->set_active( bIsLandscape ? 0 : 1 );
+            }
+        }
+        break;
+
+        case SID_ATTR_PAGE_LRSPACE:
+        {
+            const SvxLongLRSpaceItem* pLRItem = nullptr;
+            if (eState >= SfxItemState::DEFAULT)
+                pLRItem = dynamic_cast<const SvxLongLRSpaceItem*>(pState);
+            if (pLRItem)
+            {
+                mpPageLRMarginItem.reset( static_cast<SvxLongLRSpaceItem*>(pState->Clone()) );
+                UpdateMarginBox();
+            }
+        }
+        break;
+
+        case SID_ATTR_PAGE_ULSPACE:
+        {
+            const SvxLongULSpaceItem* pULItem = nullptr;
+            if (eState >= SfxItemState::DEFAULT)
+                pULItem = dynamic_cast<const SvxLongULSpaceItem*>(pState);
+            if (pULItem)
+            {
+                mpPageULMarginItem.reset( static_cast<SvxLongULSpaceItem*>(pState->Clone()) );
+                UpdateMarginBox();
+            }
+        }
+        break;
+
+        case SID_DISPLAY_MASTER_BACKGROUND:
+        {
+            const SfxBoolItem* pBoolItem = nullptr;
+            if (eState >= SfxItemState::DEFAULT)
+                pBoolItem = dynamic_cast< const SfxBoolItem* >(pState);
+            if (pBoolItem)
+                mxDspMasterBackground->set_active(pBoolItem->GetValue());
+        }
+        break;
+        case SID_DISPLAY_MASTER_OBJECTS:
+        {
+            const SfxBoolItem* pBoolItem = nullptr;
+            if (eState >= SfxItemState::DEFAULT)
+                pBoolItem = dynamic_cast< const SfxBoolItem* >(pState);
+            if (pBoolItem)
+                mxDspMasterObjects->set_active(pBoolItem->GetValue());
+        }
+        break;
+        case SID_SELECT_BACKGROUND:
+        {
+            if(eState >= SfxItemState::DEFAULT)
+            {
+                mxFillStyle->set_active(static_cast< sal_Int32 >(BITMAP));
+                Update();
+            }
+        }
+        break;
+        case SID_ATTR_METRIC:
+        {
+            FieldUnit eFUnit = GetCurrentUnit(eState, pState);
+            if (meFUnit != eFUnit)
+            {
+                meFUnit = eFUnit;
+                SetMarginsFieldUnit();
+                UpdateMarginBox();
+            }
+        }
+        break;
+        default:
+            break;
+    }
+}
+
+IMPL_LINK_NOARG(SlideBackground, FillStyleModifyHdl, weld::ComboBox&, void)
+{
+    const eFillStyle nPos = static_cast<eFillStyle>(mxFillStyle->get_active());
+    Update();
+
+    switch (nPos)
+    {
+        case NONE:
+        {
+            const XFillStyleItem aXFillStyleItem(drawing::FillStyle_NONE);
+            GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_FILLSTYLE, SfxCallMode::RECORD, { &aXFillStyleItem });
+        }
+        break;
+
+        case SOLID:
+        {
+            if (mpColorItem)
+            {
+                const XFillColorItem aItem( OUString(), mpColorItem->GetColorValue() );
+                GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_COLOR, SfxCallMode::RECORD, { &aItem });
+            }
+        }
+        break;
+
+        case GRADIENT:
+        {
+            if (mpGradientItem)
+            {
+                const XFillGradientItem aItem( mpGradientItem->GetName(), mpGradientItem->GetGradientValue() );
+                GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_GRADIENT, SfxCallMode::RECORD, { &aItem });
+            }
+        }
+        break;
+
+        case HATCH:
+        {
+            if (mpHatchItem)
+            {
+                const XFillHatchItem aItem( mpHatchItem->GetName(), mpHatchItem->GetHatchValue() );
+                GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_HATCH, SfxCallMode::RECORD, { &aItem });
+            }
+        }
+        break;
+
+        case BITMAP:
+        case PATTERN:
+        {
+            if (mpBitmapItem)
+            {
+                const XFillBitmapItem aItem( mpBitmapItem->GetName(), mpBitmapItem->GetGraphicObject() );
+                GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_BITMAP, SfxCallMode::RECORD, { &aItem });
+            }
+        }
+        break;
+
+        default:
+        break;
+    }
+//TODO    mxFillStyle->Selected();
+}
+
+IMPL_LINK_NOARG(SlideBackground, PaperSizeModifyHdl, weld::ComboBox&, void)
+{
+    const Paper ePaper = mxPaperSizeBox->get_active_id();
+    Size aSize(SvxPaperInfo::GetPaperSize(ePaper, meUnit));
+
+    if (mxPaperOrientation->get_active() == 0)
+        Swap(aSize);
+
+    mpPageItem->SetLandscape(mxPaperOrientation->get_active() == 0);
+    const SvxSizeItem aSizeItem(SID_ATTR_PAGE_SIZE, aSize);
+    // Page/slide properties dialog (FuPage::ExecuteDialog and ::ApplyItemSet) misuses
+    // SID_ATTR_PAGE_EXT1 to distinguish between Impress and Draw, as for whether to fit
+    // objects to paper size. Until that is handled somehow better, we do the same here
+    const SfxBoolItem aFitObjs(SID_ATTR_PAGE_EXT1, IsImpress());
+
+    GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_SIZE, SfxCallMode::RECORD,
+                                                { &aSizeItem, mpPageItem.get(), &aFitObjs });
+
+    // Notify LOK clients of the page size change.
+    if (!comphelper::LibreOfficeKit::isActive())
+        return;
+
+    SfxViewShell* pViewShell = SfxViewShell::GetFirst();
+    while (pViewShell)
+    {
+        if (pViewShell->GetDocId() == mrBase.GetDocId())
+        {
+            SdXImpressDocument* pDoc = comphelper::getFromUnoTunnel<SdXImpressDocument>(pViewShell->GetCurrentDocument());
+            SfxLokHelper::notifyDocumentSizeChangedAllViews(pDoc);
+        }
+        pViewShell = SfxViewShell::GetNext(*pViewShell);
+    }
+}
+
+IMPL_LINK_NOARG(SlideBackground, FillColorHdl, ColorListBox&, void)
+{
+    const drawing::FillStyle eXFS = static_cast<drawing::FillStyle>(mxFillStyle->get_active());
+    switch(eXFS)
+    {
+        case drawing::FillStyle_SOLID:
+        {
+            XFillColorItem aItem(OUString(), mxFillLB->GetSelectEntryColor());
+            GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_COLOR, SfxCallMode::RECORD, { &aItem });
+        }
+        break;
+        case drawing::FillStyle_GRADIENT:
+        {
+            XGradient aGradient;
+            aGradient.SetStartColor(mxFillGrad1->GetSelectEntryColor());
+            aGradient.SetEndColor(mxFillGrad2->GetSelectEntryColor());
+
+            // the name doesn't really matter, it'll be converted to unique one eventually,
+            // but it has to be non-empty
+            XFillGradientItem aItem("gradient", aGradient);
+            GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_GRADIENT, SfxCallMode::RECORD, { &aItem });
+        }
+        break;
+        default:
+            break;
+    }
+}
+
+IMPL_LINK_NOARG(SlideBackground, FillBackgroundHdl, weld::ComboBox&, void)
+{
+    const eFillStyle nFillPos = static_cast<eFillStyle>(mxFillStyle->get_active());
+    SfxObjectShell* pSh = SfxObjectShell::Current();
+    if (!pSh)
+        return;
+    switch(nFillPos)
+    {
+
+        case HATCH:
+        {
+            const SvxHatchListItem * pHatchListItem = pSh->GetItem(SID_HATCH_LIST);
+            sal_uInt16 nPos = mxFillAttr->get_active();
+            XHatch aHatch = pHatchListItem->GetHatchList()->GetHatch(nPos)->GetHatch();
+            const OUString aHatchName = pHatchListItem->GetHatchList()->GetHatch(nPos)->GetName();
+
+            XFillHatchItem aItem(aHatchName, aHatch);
+            GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_HATCH, SfxCallMode::RECORD, { &aItem });
+        }
+        break;
+
+        case BITMAP:
+        case PATTERN:
+        {
+            sal_Int16 nPos = mxFillAttr->get_active();
+            GraphicObject aBitmap;
+            OUString aName;
+            if( nFillPos == BITMAP )
+            {
+                SvxBitmapListItem const * pBitmapListItem = pSh->GetItem(SID_BITMAP_LIST);
+                aBitmap = pBitmapListItem->GetBitmapList()->GetBitmap(nPos)->GetGraphicObject();
+                aName = pBitmapListItem->GetBitmapList()->GetBitmap(nPos)->GetName();
+            }
+            else if( nFillPos == PATTERN )
+            {
+                SvxPatternListItem const * pPatternListItem = pSh->GetItem(SID_PATTERN_LIST);
+                aBitmap = pPatternListItem->GetPatternList()->GetBitmap(nPos)->GetGraphicObject();
+                aName = pPatternListItem->GetPatternList()->GetBitmap(nPos)->GetName();
+            }
+            XFillBitmapItem aItem(aName, aBitmap);
+            GetBindings()->GetDispatcher()->ExecuteList(SID_ATTR_PAGE_BITMAP, SfxCallMode::RECORD, { &aItem });
+        }
+        break;
+
+        default:
+            break;
+    }
+}
+
+IMPL_LINK_NOARG(SlideBackground, AssignMasterPage, weld::ComboBox&, void)
+{
+    ::sd::DrawDocShell* pDocSh = dynamic_cast<::sd::DrawDocShell*>( SfxObjectShell::Current() );
+    SdDrawDocument* pDoc = pDocSh ? pDocSh->GetDoc() : nullptr;
+    if (!pDoc)
+        return;
+
+    auto pSSVS = sd::slidesorter::SlideSorterViewShell::GetSlideSorter(mrBase);
+    if (pSSVS == nullptr)
+        return;
+
+    auto& rSSController = pSSVS->GetSlideSorter().GetController();
+    auto& rPageSelector = rSSController.GetPageSelector();
+
+    for( sal_uInt16 nPage = 0; nPage < pDoc->GetSdPageCount(PageKind::Standard); nPage++ )
+    {
+        if (rPageSelector.IsPageSelected(nPage))
+        {
+            OUString aLayoutName(mxMasterSlide->get_active_text());
+            pDoc->SetMasterPage(nPage, aLayoutName, pDoc, false, false);
+        }
+    }
+}
+
+IMPL_LINK_NOARG(SlideBackground, EditMasterHdl, weld::Button&, void)
+{
+    GetBindings()->GetDispatcher()->Execute( SID_SLIDE_MASTER_MODE, SfxCallMode::RECORD );
+}
+
+IMPL_LINK_NOARG(SlideBackground, SelectBgHdl, weld::Button&, void)
+{
+    GetBindings()->GetDispatcher()->Execute( SID_SELECT_BACKGROUND, SfxCallMode::RECORD );
+}
+
+IMPL_LINK_NOARG(SlideBackground, CloseMasterHdl, weld::Button&, void)
+{
+    GetBindings()->GetDispatcher()->Execute( SID_CLOSE_MASTER_VIEW, SfxCallMode::RECORD );
+}
+
+IMPL_LINK_NOARG(SlideBackground, DspBackground, weld::Toggleable&, void)
+{
+    bool IsChecked = mxDspMasterBackground->get_active();
+    const SfxBoolItem aBoolItem(SID_DISPLAY_MASTER_BACKGROUND, IsChecked);
+    GetBindings()->GetDispatcher()->ExecuteList(SID_DISPLAY_MASTER_BACKGROUND, SfxCallMode::RECORD, { &aBoolItem });
+}
+
+IMPL_LINK_NOARG(SlideBackground, DspObjects, weld::Toggleable&, void)
+{
+    bool IsChecked = mxDspMasterObjects->get_active();
+    const SfxBoolItem aBoolItem(SID_DISPLAY_MASTER_OBJECTS,IsChecked);
+    GetBindings()->GetDispatcher()->ExecuteList(SID_DISPLAY_MASTER_OBJECTS, SfxCallMode::RECORD, { &aBoolItem, &aBoolItem });
+}
+
+IMPL_LINK_NOARG( SlideBackground, ModifyMarginHdl, weld::ComboBox&, void )
+{
+    bool bApplyNewPageMargins = true;
+    switch ( mxMarginSelectBox->get_active() )
+    {
+        case 0:
+            SetNone(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin);
+            break;
+        case 1:
+            SetNarrow(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin);
+            break;
+        case 2:
+            SetModerate(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin);
+            break;
+        case 3:
+            SetNormal075(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin);
+            break;
+        case 4:
+            SetNormal100(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin);
+            break;
+        case 5:
+            SetNormal125(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin);
+            break;
+        case 6:
+            SetWide(m_nPageLeftMargin, m_nPageRightMargin, m_nPageTopMargin, m_nPageBottomMargin);
+            break;
+        default:
+            bApplyNewPageMargins = false;
+            break;
+    }
+
+    if(bApplyNewPageMargins)
+    {
+        ExecuteMarginLRChange(m_nPageLeftMargin, m_nPageRightMargin);
+        ExecuteMarginULChange(m_nPageTopMargin, m_nPageBottomMargin);
+    }
+}
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/sidebar/SlideBackground.hxx b/sd/source/ui/sidebar/SlideBackground.hxx
new file mode 100644
index 000000000..25af0a4af
--- /dev/null
+++ b/sd/source/ui/sidebar/SlideBackground.hxx
@@ -0,0 +1,180 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <memory>
+#include <sfx2/sidebar/PanelLayout.hxx>
+#include <sfx2/sidebar/ControllerItem.hxx>
+#include <svx/papersizelistbox.hxx>
+#include <sfx2/sidebar/IContextChangeReceiver.hxx>
+#include <vcl/EnumContext.hxx>
+
+#include <com/sun/star/frame/XFrame.hpp>
+
+namespace sd { class ViewShellBase; }
+namespace sd::tools { class EventMultiplexerEvent; }
+
+class ColorListBox;
+class SvxPageItem;
+class SvxLongLRSpaceItem;
+class SvxLongULSpaceItem;
+class XFillColorItem;
+class XGradient;
+class XFillGradientItem;
+class XFillBitmapItem;
+class XFillHatchItem;
+
+namespace sd::sidebar {
+
+class SlideBackground :
+    public PanelLayout,
+    public ::sfx2::sidebar::IContextChangeReceiver,
+    public ::sfx2::sidebar::ControllerItem::ItemUpdateReceiverInterface
+{
+public:
+    SlideBackground(
+        weld::Widget* pParent,
+        ViewShellBase& rBase,
+        const css::uno::Reference<css::frame::XFrame>& rxFrame,
+        SfxBindings* pBindings );
+    virtual ~SlideBackground() override;
+    SfxBindings* GetBindings() { return mpBindings; }
+    // Window
+    virtual void NotifyItemUpdate(
+        const sal_uInt16 nSID,
+        const SfxItemState eState,
+        const SfxPoolItem* pState) override;
+
+    virtual void GetControlState(
+        const sal_uInt16 /*nSId*/,
+        boost::property_tree::ptree& /*rState*/) override {};
+
+    virtual void HandleContextChange(
+        const vcl::EnumContext& rContext) override;
+    virtual void DumpAsPropertyTree(::tools::JsonWriter&) override;
+
+private:
+
+    ViewShellBase& mrBase;
+
+    std::unique_ptr<SvxPaperSizeListBox> mxPaperSizeBox;
+    std::unique_ptr<weld::ComboBox> mxPaperOrientation;
+    std::unique_ptr<weld::ComboBox> mxMasterSlide;
+    std::unique_ptr<weld::Label> mxBackgroundLabel;
+    std::unique_ptr<weld::ComboBox> mxFillStyle;
+    std::unique_ptr<ColorListBox> mxFillLB;
+    std::unique_ptr<weld::ComboBox> mxFillAttr;
+    std::unique_ptr<ColorListBox> mxFillGrad1;
+    std::unique_ptr<ColorListBox> mxFillGrad2;
+    std::unique_ptr<weld::Button> mxInsertImage;
+    std::unique_ptr<weld::CheckButton> mxDspMasterBackground;
+    std::unique_ptr<weld::CheckButton> mxDspMasterObjects;
+    std::unique_ptr<weld::Button> mxCloseMaster;
+    std::unique_ptr<weld::Button> mxEditMaster;
+    std::unique_ptr<weld::Label> mxMasterLabel;
+    std::unique_ptr<weld::ComboBox> mxMarginSelectBox;
+    std::unique_ptr<weld::Label> mxCustomEntry;
+    std::unique_ptr<weld::Label> mxMarginLabel;
+
+    ::sfx2::sidebar::ControllerItem maPaperSizeController;
+    ::sfx2::sidebar::ControllerItem maPaperOrientationController;
+    ::sfx2::sidebar::ControllerItem maPaperMarginLRController;
+    ::sfx2::sidebar::ControllerItem maPaperMarginULController;
+    ::sfx2::sidebar::ControllerItem maBckColorController;
+    ::sfx2::sidebar::ControllerItem maBckGradientController;
+    ::sfx2::sidebar::ControllerItem maBckHatchController;
+    ::sfx2::sidebar::ControllerItem maBckBitmapController;
+    ::sfx2::sidebar::ControllerItem maBckFillStyleController;
+    ::sfx2::sidebar::ControllerItem maBckImageController;
+    ::sfx2::sidebar::ControllerItem maDspBckController;
+    ::sfx2::sidebar::ControllerItem maDspObjController;
+    ::sfx2::sidebar::ControllerItem maMetricController;
+    ::sfx2::sidebar::ControllerItem maCloseMasterController;
+
+    std::unique_ptr< SvxPageItem >          mpPageItem;
+    std::unique_ptr< XFillColorItem >       mpColorItem;
+    std::unique_ptr< XFillGradientItem >    mpGradientItem;
+    std::unique_ptr< XFillHatchItem >       mpHatchItem;
+    std::unique_ptr< XFillBitmapItem >      mpBitmapItem;
+
+    bool mbSwitchModeToNormal;
+    bool mbSwitchModeToMaster;
+
+    css::uno::Reference<css::frame::XFrame> mxFrame;
+    vcl::EnumContext maContext;
+    vcl::EnumContext maDrawOtherContext;
+    vcl::EnumContext maDrawMasterContext;
+    vcl::EnumContext maImpressOtherContext;
+    vcl::EnumContext maImpressMasterContext;
+    vcl::EnumContext maImpressHandoutContext;
+    vcl::EnumContext maImpressNotesContext;
+    bool         mbTitle;
+    std::unique_ptr<SvxLongLRSpaceItem> mpPageLRMarginItem;
+    std::unique_ptr<SvxLongULSpaceItem> mpPageULMarginItem;
+    ::tools::Long m_nPageLeftMargin;
+    ::tools::Long m_nPageRightMargin;
+    ::tools::Long m_nPageTopMargin;
+    ::tools::Long m_nPageBottomMargin;
+    FieldUnit meFUnit;
+    OUString maCustomEntry;
+
+    SfxBindings* mpBindings;
+
+    MapUnit meUnit;
+
+    DECL_LINK(FillBackgroundHdl, weld::ComboBox&, void);
+    DECL_LINK(FillStyleModifyHdl, weld::ComboBox&, void);
+    DECL_LINK(PaperSizeModifyHdl, weld::ComboBox&, void);
+    DECL_LINK(FillColorHdl, ColorListBox&, void);
+    DECL_LINK(AssignMasterPage, weld::ComboBox&, void);
+    DECL_LINK(DspBackground, weld::Toggleable&, void);
+    DECL_LINK(DspObjects, weld::Toggleable&, void);
+    DECL_LINK(CloseMasterHdl, weld::Button&, void);
+    DECL_LINK(EditMasterHdl, weld::Button&, void);
+    DECL_LINK(SelectBgHdl, weld::Button&, void);
+    DECL_LINK(EventMultiplexerListener, tools::EventMultiplexerEvent&, void );
+    DECL_LINK( ModifyMarginHdl, weld::ComboBox&, void );
+
+    void Initialize();
+    void Update();
+    void UpdateMarginBox();
+    void SetPanelTitle(const OUString& rTitle);
+    void SetMarginsFieldUnit();
+
+    Color const & GetColorSetOrDefault();
+    XGradient const & GetGradientSetOrDefault();
+    OUString const & GetHatchingSetOrDefault();
+    OUString const & GetBitmapSetOrDefault();
+    OUString const & GetPatternSetOrDefault();
+    bool IsDraw();
+    bool IsImpress();
+    void addListener();
+    void removeListener();
+    void ExecuteMarginLRChange(const ::tools::Long mnPageLeftMargin, const ::tools::Long mnPageRightMargin);
+    void ExecuteMarginULChange(const ::tools::Long mnPageTopMargin, const ::tools::Long mnPageBottomMargin);
+    void populateMasterSlideDropdown();
+    void updateMasterSlideSelection();
+
+    static FieldUnit GetCurrentUnit(SfxItemState eState, const SfxPoolItem* pState);
+};
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */