Adding upstream version 4:24.2.0.upstream/4%24.2.0

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

1 files changed, 1168 insertions, 0 deletions

diff --git a/sd/source/ui/view/ViewShellManager.cxx b/sd/source/ui/view/ViewShellManager.cxx
new file mode 100644
index 0000000000..db2ee5f8f1
--- /dev/null
+++ b/sd/source/ui/view/ViewShellManager.cxx
@@ -0,0 +1,1168 @@
+/* -*- 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 <ViewShellManager.hxx>
+#include <ViewShell.hxx>
+#include <ViewShellBase.hxx>
+#include <Window.hxx>
+#include <DrawDocShell.hxx>
+
+#include <sal/log.hxx>
+#include <sfx2/dispatch.hxx>
+#include <sfx2/viewfrm.hxx>
+#include <svx/svxids.hrc>
+#include <svx/fmshell.hxx>
+#include <vcl/vclevent.hxx>
+#include <osl/diagnose.h>
+
+#include <iterator>
+#include <list>
+#include <unordered_map>
+
+namespace sd {
+
+namespace {
+
+/** The ShellDescriptor class is used to shells together with their ids and
+    the factory that was used to create the shell.
+
+    The shell pointer may be NULL.  In that case the shell is created on
+    demand by a factory.
+
+    The factory pointer may be NULL.  In that case the shell pointer is
+    given to the ViewShellManager.
+
+    Shell pointer and factory pointer can but should not be NULL at the same
+    time.
+*/
+class ShellDescriptor {
+public:
+    SfxShell* mpShell;
+    ShellId mnId;
+    ViewShellManager::SharedShellFactory mpFactory;
+    bool mbIsListenerAddedToWindow;
+
+    ShellDescriptor ();
+    explicit ShellDescriptor (ShellId nId);
+    vcl::Window* GetWindow() const;
+};
+
+/** This functor can be used to search for a shell in an STL container when the
+    shell pointer is given.
+*/
+class IsShell
+{
+public:
+    explicit IsShell (const SfxShell* pShell) : mpShell(pShell) {}
+    bool operator() (const ShellDescriptor& rDescriptor)
+    { return rDescriptor.mpShell == mpShell; }
+private:
+    const SfxShell* mpShell;
+};
+
+/** This functor can be used to search for a shell in an STL container when the
+    id of the shell is given.
+*/
+class IsId
+{
+public:
+    explicit IsId (ShellId nId) : mnId(nId) {}
+    bool operator() (const ShellDescriptor& rDescriptor)
+    { return rDescriptor.mnId == mnId; }
+private:
+    ShellId mnId;
+};
+
+} // end of anonymous namespace
+
+class ViewShellManager::Implementation
+{
+public:
+    Implementation (
+        ViewShellBase& rBase);
+    ~Implementation() COVERITY_NOEXCEPT_FALSE;
+
+    void AddShellFactory (
+        const SfxShell* pViewShell,
+        const SharedShellFactory& rpFactory);
+    void RemoveShellFactory (
+        const SfxShell* pViewShell,
+        const SharedShellFactory& rpFactory);
+    void ActivateViewShell (
+        ViewShell* pViewShell);
+    void DeactivateViewShell (const ViewShell& rShell);
+    void ActivateShell (SfxShell& rShell);
+    void DeactivateShell (const SfxShell& rShell);
+    void ActivateShell (const ShellDescriptor& rDescriptor);
+    void SetFormShell (const ViewShell* pViewShell, FmFormShell* pFormShell, bool bAbove);
+    void ActivateSubShell (const SfxShell& rParentShell, ShellId nId);
+    void DeactivateSubShell (const SfxShell& rParentShell, ShellId nId);
+    void MoveToTop (const SfxShell& rParentShell);
+    SfxShell* GetShell (ShellId nId) const;
+    SfxShell* GetTopShell() const;
+    SfxShell* GetTopViewShell() const;
+    void Shutdown();
+    void InvalidateAllSubShells (const SfxShell* pParentShell);
+
+    /** Remove all shells from the SFX stack above and including the given
+        shell.
+    */
+    void TakeShellsFromStack (const SfxShell* pShell);
+
+    class UpdateLock
+    {
+    public:
+        explicit UpdateLock (Implementation& rImpl) : mrImpl(rImpl) {mrImpl.LockUpdate();}
+        ~UpdateLock() COVERITY_NOEXCEPT_FALSE {mrImpl.UnlockUpdate();}
+    private:
+        Implementation& mrImpl;
+    };
+
+    /** Prevent updates of the shell stack.  While the sub shell manager is
+        locked it will update its internal data structures but not alter the
+        shell stack.  Use this method when there are several modifications
+        to the shell stack to prevent multiple rebuilds of the shell stack
+        and resulting broadcasts.
+    */
+    void LockUpdate();
+
+    /** Allow updates of the shell stack.  This method has to be called the
+        same number of times as LockUpdate() to really allow a rebuild of
+        the shell stack.
+    */
+    void UnlockUpdate();
+
+private:
+    ViewShellBase& mrBase;
+    mutable ::osl::Mutex maMutex;
+
+    class ShellHash { public: size_t operator()(const SfxShell* p) const { return reinterpret_cast<size_t>(p);} };
+    typedef std::unordered_multimap<const SfxShell*,SharedShellFactory,ShellHash>
+        FactoryList;
+    FactoryList maShellFactories;
+
+    /** List of the active view shells.  In order to create gather all shells
+        to put on the shell stack each view shell in this list is asked for
+        its sub-shells (typically toolbars).
+    */
+    typedef std::list<ShellDescriptor> ActiveShellList;
+    ActiveShellList maActiveViewShells;
+
+    typedef std::list<ShellDescriptor> SubShellSubList;
+    typedef std::unordered_map<const SfxShell*,SubShellSubList,ShellHash> SubShellList;
+    SubShellList maActiveSubShells;
+
+    /** In this member we remember what shells we have pushed on the shell
+        stack.
+    */
+    typedef ::std::vector<SfxShell*> ShellStack;
+
+    int mnUpdateLockCount;
+
+    /** The UpdateShellStack() method can be called recursively.  This flag
+        is used to communicate between different levels of invocation: if
+        the stack has been updated in an inner call the outer call can (has
+        to) stop and return immediately.
+    */
+    bool mbShellStackIsUpToDate;
+
+    SfxShell* mpFormShell;
+    const ViewShell* mpFormShellParent;
+    bool mbFormShellAboveParent;
+
+    SfxShell* mpTopShell;
+    SfxShell* mpTopViewShell;
+
+
+    void UpdateShellStack();
+
+    void CreateShells();
+
+    /** This method rebuilds the stack of shells that are stacked upon the
+        view shell base.
+    */
+    void CreateTargetStack (ShellStack& rStack) const;
+
+    DECL_LINK(WindowEventHandler, VclWindowEvent&, void);
+
+#if OSL_DEBUG_LEVEL >= 2
+    void DumpShellStack (const ShellStack& rStack);
+    void DumpSfxShellStack();
+#endif
+
+    /** To be called before a shell is taken from the SFX shell stack.  This
+        method deactivates an active text editing to avoid problems with
+        undo managers.
+        Afterwards the Deactivate() of the shell is called.
+    */
+    static void Deactivate (SfxShell* pShell);
+
+    ShellDescriptor CreateSubShell (
+        SfxShell const * pShell,
+        ShellId nShellId);
+    void DestroyViewShell (ShellDescriptor& rDescriptor);
+    static void DestroySubShell (const ShellDescriptor& rDescriptor);
+};
+
+//===== ViewShellManager ======================================================
+
+ViewShellManager::ViewShellManager (ViewShellBase& rBase)
+    : mpImpl(new Implementation(rBase)),
+      mbValid(true)
+{
+}
+
+ViewShellManager::~ViewShellManager()
+{
+}
+
+void ViewShellManager::AddSubShellFactory (
+    ViewShell const * pViewShell,
+    const SharedShellFactory& rpFactory)
+{
+    if (mbValid)
+        mpImpl->AddShellFactory(pViewShell, rpFactory);
+}
+
+void ViewShellManager::RemoveSubShellFactory (
+    ViewShell const * pViewShell,
+    const SharedShellFactory& rpFactory)
+{
+    if (mbValid)
+        mpImpl->RemoveShellFactory(pViewShell, rpFactory);
+}
+
+void ViewShellManager::ActivateViewShell (ViewShell* pViewShell)
+{
+    if (mbValid)
+        return mpImpl->ActivateViewShell(pViewShell);
+}
+
+void ViewShellManager::DeactivateViewShell (const ViewShell* pShell)
+{
+    if (mbValid && pShell!=nullptr)
+        mpImpl->DeactivateViewShell(*pShell);
+}
+
+void ViewShellManager::SetFormShell (
+    const ViewShell* pParentShell,
+    FmFormShell* pFormShell,
+    bool bAbove)
+{
+    if (mbValid)
+        mpImpl->SetFormShell(pParentShell,pFormShell,bAbove);
+}
+
+void ViewShellManager::ActivateSubShell (const ViewShell& rViewShell, ShellId nId)
+{
+    if (mbValid)
+        mpImpl->ActivateSubShell(rViewShell,nId);
+}
+
+void ViewShellManager::DeactivateSubShell (const ViewShell& rViewShell, ShellId nId)
+{
+    if (mbValid)
+        mpImpl->DeactivateSubShell(rViewShell,nId);
+}
+
+void ViewShellManager::InvalidateAllSubShells (ViewShell const * pViewShell)
+{
+    if (mbValid)
+        mpImpl->InvalidateAllSubShells(pViewShell);
+}
+
+void ViewShellManager::ActivateShell (SfxShell* pShell)
+{
+    if (mbValid && pShell!=nullptr)
+        mpImpl->ActivateShell(*pShell);
+}
+
+void ViewShellManager::DeactivateShell (const SfxShell* pShell)
+{
+    if (mbValid && pShell!=nullptr)
+        mpImpl->DeactivateShell(*pShell);
+}
+
+void ViewShellManager::MoveToTop (const ViewShell& rParentShell)
+{
+    if (mbValid)
+        mpImpl->MoveToTop(rParentShell);
+}
+
+SfxShell* ViewShellManager::GetShell (ShellId nId) const
+{
+    if (mbValid)
+        return mpImpl->GetShell(nId);
+    else
+        return nullptr;
+}
+
+SfxShell* ViewShellManager::GetTopShell() const
+{
+    if (mbValid)
+        return mpImpl->GetTopShell();
+    else
+        return nullptr;
+}
+
+SfxShell* ViewShellManager::GetTopViewShell() const
+{
+    if (mbValid)
+        return mpImpl->GetTopViewShell();
+    else
+        return nullptr;
+}
+
+void ViewShellManager::Shutdown()
+{
+    if (mbValid)
+    {
+        mpImpl->Shutdown();
+        mbValid = false;
+    }
+}
+
+void ViewShellManager::LockUpdate()
+{
+    mpImpl->LockUpdate();
+}
+
+void ViewShellManager::UnlockUpdate()
+{
+    mpImpl->UnlockUpdate();
+}
+
+//===== ViewShellManager::Implementation ======================================
+
+ViewShellManager::Implementation::Implementation (
+    ViewShellBase& rBase)
+    : mrBase(rBase),
+      mnUpdateLockCount(0),
+      mbShellStackIsUpToDate(true),
+      mpFormShell(nullptr),
+      mpFormShellParent(nullptr),
+      mbFormShellAboveParent(true),
+      mpTopShell(nullptr),
+      mpTopViewShell(nullptr)
+{}
+
+ViewShellManager::Implementation::~Implementation() COVERITY_NOEXCEPT_FALSE
+{
+    Shutdown();
+}
+
+void ViewShellManager::Implementation::AddShellFactory (
+    const SfxShell* pViewShell,
+    const SharedShellFactory& rpFactory)
+{
+    bool bAlreadyAdded (false);
+
+    // Check that the given factory has not already been added.
+    ::std::pair<FactoryList::iterator,FactoryList::iterator> aRange(
+        maShellFactories.equal_range(pViewShell));
+    for (FactoryList::const_iterator iFactory=aRange.first; iFactory!=aRange.second; ++iFactory)
+        if (iFactory->second == rpFactory)
+        {
+            bAlreadyAdded = true;
+            break;
+        }
+
+    // Add the factory if it is not already present.
+    if ( ! bAlreadyAdded)
+        maShellFactories.emplace(pViewShell, rpFactory);
+}
+
+void ViewShellManager::Implementation::RemoveShellFactory (
+    const SfxShell* pViewShell,
+    const SharedShellFactory& rpFactory)
+{
+    ::std::pair<FactoryList::iterator,FactoryList::iterator> aRange(
+        maShellFactories.equal_range(pViewShell));
+    for (FactoryList::iterator iFactory=aRange.first; iFactory!=aRange.second; ++iFactory)
+        if (iFactory->second == rpFactory)
+        {
+            maShellFactories.erase(iFactory);
+            break;
+        }
+}
+
+void ViewShellManager::Implementation::ActivateViewShell (ViewShell* pViewShell)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    ShellDescriptor aResult;
+    aResult.mpShell = pViewShell;
+
+    // Register as window listener so that the shells of the current
+    // window can be moved to the top of the shell stack.
+    if (aResult.mpShell != nullptr)
+    {
+        vcl::Window* pWindow = aResult.GetWindow();
+        if (pWindow != nullptr)
+        {
+            pWindow->AddEventListener(
+                LINK(this, ViewShellManager::Implementation, WindowEventHandler));
+            aResult.mbIsListenerAddedToWindow = true;
+        }
+        else
+        {
+            SAL_WARN("sd.view",
+                "ViewShellManager::ActivateViewShell: "
+                "new view shell has no active window");
+        }
+    }
+
+    ActivateShell(aResult);
+}
+
+void ViewShellManager::Implementation::DeactivateViewShell (const ViewShell& rShell)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    ActiveShellList::iterator iShell (::std::find_if (
+        maActiveViewShells.begin(),
+        maActiveViewShells.end(),
+        IsShell(&rShell)));
+    if (iShell == maActiveViewShells.end())
+        return;
+
+    UpdateLock aLocker (*this);
+
+    ShellDescriptor aDescriptor(*iShell);
+    mrBase.GetDocShell()->Disconnect(dynamic_cast<ViewShell*>(aDescriptor.mpShell));
+    maActiveViewShells.erase(iShell);
+    TakeShellsFromStack(aDescriptor.mpShell);
+
+    // Deactivate sub shells.
+    SubShellList::iterator iList (maActiveSubShells.find(&rShell));
+    if (iList != maActiveSubShells.end())
+    {
+        SubShellSubList& rList (iList->second);
+        while ( ! rList.empty())
+            DeactivateSubShell(rShell, rList.front().mnId);
+    }
+
+    DestroyViewShell(aDescriptor);
+}
+
+void ViewShellManager::Implementation::ActivateShell (SfxShell& rShell)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Create a new shell or recycle on in the cache.
+    ShellDescriptor aDescriptor;
+    aDescriptor.mpShell = &rShell;
+
+    ActivateShell(aDescriptor);
+}
+
+void ViewShellManager::Implementation::ActivateShell (const ShellDescriptor& rDescriptor)
+{
+    // Put shell on top of the active view shells.
+    if (rDescriptor.mpShell != nullptr)
+    {
+        maActiveViewShells.insert( maActiveViewShells.begin(), rDescriptor);
+    }
+}
+
+void ViewShellManager::Implementation::DeactivateShell (const SfxShell& rShell)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    ActiveShellList::iterator iShell (::std::find_if (
+        maActiveViewShells.begin(),
+        maActiveViewShells.end(),
+        IsShell(&rShell)));
+    if (iShell == maActiveViewShells.end())
+        return;
+
+    UpdateLock aLocker (*this);
+
+    ShellDescriptor aDescriptor(*iShell);
+    mrBase.GetDocShell()->Disconnect(dynamic_cast<ViewShell*>(aDescriptor.mpShell));
+    maActiveViewShells.erase(iShell);
+    TakeShellsFromStack(aDescriptor.mpShell);
+
+    // Deactivate sub shells.
+    SubShellList::iterator iList (maActiveSubShells.find(&rShell));
+    if (iList != maActiveSubShells.end())
+    {
+        SubShellSubList& rList (iList->second);
+        while ( ! rList.empty())
+            DeactivateSubShell(rShell, rList.front().mnId);
+    }
+
+    DestroyViewShell(aDescriptor);
+}
+
+void ViewShellManager::Implementation::ActivateSubShell (
+    const SfxShell& rParentShell,
+    ShellId nId)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Check that the given view shell is active.
+    if (std::none_of (maActiveViewShells.begin(), maActiveViewShells.end(), IsShell(&rParentShell)))
+        return;
+
+    // Create the sub shell list if it does not yet exist.
+    SubShellList::iterator iList (maActiveSubShells.find(&rParentShell));
+    if (iList == maActiveSubShells.end())
+        iList = maActiveSubShells.emplace(&rParentShell,SubShellSubList()).first;
+
+    // Do not activate an object bar that is already active.  Requesting
+    // this is not exactly an error but may be an indication of one.
+    SubShellSubList& rList (iList->second);
+    if (std::any_of(rList.begin(),rList.end(), IsId(nId)))
+        return;
+
+    // Add just the id of the sub shell. The actual shell is created
+    // later in CreateShells().
+    UpdateLock aLock (*this);
+    rList.emplace_back(nId);
+}
+
+void ViewShellManager::Implementation::DeactivateSubShell (
+    const SfxShell& rParentShell,
+    ShellId nId)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Check that the given view shell is active.
+    SubShellList::iterator iList (maActiveSubShells.find(&rParentShell));
+    if (iList == maActiveSubShells.end())
+        return;
+
+    // Look up the sub shell.
+    SubShellSubList& rList (iList->second);
+    SubShellSubList::iterator iShell (
+        ::std::find_if(rList.begin(),rList.end(), IsId(nId)));
+    if (iShell == rList.end())
+        return;
+    SfxShell* pShell = iShell->mpShell;
+    if (pShell == nullptr)
+        return;
+
+    UpdateLock aLock (*this);
+
+    ShellDescriptor aDescriptor(*iShell);
+    // Remove the sub shell from both the internal structure as well as the
+    // SFX shell stack above and including the sub shell.
+    rList.erase(iShell);
+    TakeShellsFromStack(pShell);
+
+    DestroySubShell(aDescriptor);
+}
+
+void ViewShellManager::Implementation::MoveToTop (const SfxShell& rShell)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Check that we have access to a dispatcher.  If not, then we are
+    // (probably) called while the view shell is still being created or
+    // initialized.  Without dispatcher we can not rebuild the shell stack
+    // to move the requested shell to the top.  So return right away instead
+    // of making a mess without being able to clean up afterwards.
+    if (mrBase.GetDispatcher() == nullptr)
+        return;
+
+    ActiveShellList::iterator iShell (::std::find_if (
+        maActiveViewShells.begin(),
+        maActiveViewShells.end(),
+        IsShell(&rShell)));
+    bool bMove = true;
+    if (iShell != maActiveViewShells.end())
+    {
+        // Is the shell already at the top of the stack?  We have to keep
+        // the case in mind that mbKeepMainViewShellOnTop is true.  Shells
+        // that are not the main view shell are placed on the second-to-top
+        // position in this case.
+        if (iShell == maActiveViewShells.begin())
+        {
+            // The shell is at the top position and is either a) the main
+            // view shell or b) another shell but the main view shell is not
+            // kept at the top position.  We do not have to move the shell.
+            bMove = false;
+        }
+    }
+    else
+    {
+        // The shell is not on the stack.  Therefore it can not be moved.
+        // We could insert it but we don't.  Use ActivateViewShell() for
+        // that.
+        bMove = false;
+    }
+
+    // When the shell is not at the right position it is removed from the
+    // internal list of shells and inserted at the correct position.
+    if (bMove)
+    {
+        UpdateLock aLock (*this);
+
+        ShellDescriptor aDescriptor(*iShell);
+
+        TakeShellsFromStack(&rShell);
+        maActiveViewShells.erase(iShell);
+
+        maActiveViewShells.insert(maActiveViewShells.begin(), aDescriptor);
+    }
+}
+
+SfxShell* ViewShellManager::Implementation::GetShell (ShellId nId) const
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    SfxShell* pShell = nullptr;
+
+    // First search the active view shells.
+    ActiveShellList::const_iterator iShell (
+        ::std::find_if (
+        maActiveViewShells.begin(),
+        maActiveViewShells.end(),
+        IsId(nId)));
+    if (iShell != maActiveViewShells.end())
+        pShell = iShell->mpShell;
+    else
+    {
+        // Now search the active sub shells of every active view shell.
+        for (auto const& activeSubShell : maActiveSubShells)
+        {
+            const SubShellSubList& rList (activeSubShell.second);
+            SubShellSubList::const_iterator iSubShell(
+                ::std::find_if(rList.begin(),rList.end(), IsId(nId)));
+            if (iSubShell != rList.end())
+            {
+                pShell = iSubShell->mpShell;
+                break;
+            }
+        }
+    }
+
+    return pShell;
+}
+
+SfxShell* ViewShellManager::Implementation::GetTopShell() const
+{
+    OSL_ASSERT(mpTopShell == mrBase.GetSubShell(0));
+    return mpTopShell;
+}
+
+SfxShell* ViewShellManager::Implementation::GetTopViewShell() const
+{
+    return mpTopViewShell;
+}
+
+void ViewShellManager::Implementation::LockUpdate()
+{
+    mnUpdateLockCount++;
+}
+
+void ViewShellManager::Implementation::UnlockUpdate()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    mnUpdateLockCount--;
+    if (mnUpdateLockCount < 0)
+    {
+        // This should not happen.
+        OSL_ASSERT (mnUpdateLockCount>=0);
+        mnUpdateLockCount = 0;
+    }
+    if (mnUpdateLockCount == 0)
+        UpdateShellStack();
+}
+
+/** Update the SFX shell stack (the portion that is visible to us) so that
+    it matches the internal shell stack.  This is done in six steps:
+    1. Create the missing view shells and sub shells.
+    2. Set up the internal shell stack.
+    3. Get the SFX shell stack.
+    4. Find the lowest shell in which the two stacks differ.
+    5. Remove all shells above and including that shell from the SFX stack.
+    6. Push all shells of the internal stack on the SFX shell stack that are
+    not already present on the later.
+*/
+void ViewShellManager::Implementation::UpdateShellStack()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Remember the undo manager from the top-most shell on the stack.
+    SfxShell* pTopMostShell = mrBase.GetSubShell(0);
+    SfxUndoManager* pUndoManager = (pTopMostShell!=nullptr)
+        ? pTopMostShell->GetUndoManager()
+        : nullptr;
+
+    // 1. Create the missing shells.
+    CreateShells();
+
+    // Update the pointer to the top-most active view shell.
+    mpTopViewShell = (maActiveViewShells.empty())
+        ? nullptr : maActiveViewShells.begin()->mpShell;
+
+
+    // 2. Create the internal target stack.
+    ShellStack aTargetStack;
+    CreateTargetStack(aTargetStack);
+
+    // 3. Get SFX shell stack.
+    ShellStack aSfxShellStack;
+    sal_uInt16 nIndex (0);
+    while (mrBase.GetSubShell(nIndex)!=nullptr)
+        ++nIndex;
+    aSfxShellStack.reserve(nIndex);
+    while (nIndex-- > 0)
+        aSfxShellStack.push_back(mrBase.GetSubShell(nIndex));
+
+#if OSL_DEBUG_LEVEL >= 2
+    SAL_INFO("sd.view", __func__ << ": Current SFX Stack");
+    DumpShellStack(aSfxShellStack);
+    SAL_INFO("sd.view", __func__ << ": Target Stack");
+    DumpShellStack(aTargetStack);
+#endif
+
+    // 4. Find the lowest shell in which the two stacks differ.
+    auto mismatchIters = std::mismatch(aSfxShellStack.begin(), aSfxShellStack.end(),
+        aTargetStack.begin(), aTargetStack.end());
+    ShellStack::iterator iSfxShell (mismatchIters.first);
+    ShellStack::iterator iTargetShell (mismatchIters.second);
+
+    // 5. Remove all shells above and including the differing shell from the
+    // SFX stack starting with the shell on top of the stack.
+    for (std::reverse_iterator<ShellStack::const_iterator> i(aSfxShellStack.end()), iLast(iSfxShell);
+            i != iLast; ++i)
+    {
+        SfxShell* const pShell = *i;
+        SAL_INFO("sd.view", __func__ << ": removing shell " << pShell << " from stack");
+        mrBase.RemoveSubShell(pShell);
+    }
+    aSfxShellStack.erase(iSfxShell, aSfxShellStack.end());
+
+    // 6. Push shells from the given stack onto the SFX stack.
+    mbShellStackIsUpToDate = false;
+    while (iTargetShell != aTargetStack.end())
+    {
+        SAL_INFO("sd.view", __func__ << ": pushing shell " << *iTargetShell << " on stack");
+        mrBase.AddSubShell(**iTargetShell);
+        ++iTargetShell;
+
+        // The pushing of the shell on to the shell stack may have lead to
+        // another invocation of this method.  In this case we have to abort
+        // pushing shells on the stack and return immediately.
+        if (mbShellStackIsUpToDate)
+            break;
+    }
+    if (mrBase.GetDispatcher() != nullptr)
+        mrBase.GetDispatcher()->Flush();
+
+    // Update the pointer to the top-most shell and set its undo manager
+    // to the one of the previous top-most shell.
+    mpTopShell = mrBase.GetSubShell(0);
+    if (mpTopShell!=nullptr && pUndoManager!=nullptr && mpTopShell->GetUndoManager()==nullptr)
+        mpTopShell->SetUndoManager(pUndoManager);
+
+    // Finally tell an invocation of this method on a higher level that it can (has
+    // to) abort and return immediately.
+    mbShellStackIsUpToDate = true;
+
+#if OSL_DEBUG_LEVEL >= 2
+    SAL_INFO("sd.view", __func__ << ": New current stack");
+    DumpSfxShellStack();
+#endif
+}
+
+void ViewShellManager::Implementation::TakeShellsFromStack (const SfxShell* pShell)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Remember the undo manager from the top-most shell on the stack.
+    SfxShell* pTopMostShell = mrBase.GetSubShell(0);
+    SfxUndoManager* pUndoManager = (pTopMostShell!=nullptr)
+        ? pTopMostShell->GetUndoManager()
+        : nullptr;
+
+#if OSL_DEBUG_LEVEL >= 2
+    SAL_INFO("sd.view", __func__ << "TakeShellsFromStack( " << pShell << ")");
+    DumpSfxShellStack();
+#endif
+
+    // 0.Make sure that the given shell is on the stack.  This is a
+    // preparation for the following assertion.
+    for (sal_uInt16 nIndex=0; true; nIndex++)
+    {
+        SfxShell* pShellOnStack = mrBase.GetSubShell(nIndex);
+        if (pShellOnStack == nullptr)
+        {
+            // Set pShell to NULL to indicate the following code that the
+            // shell is not on the stack.
+            pShell = nullptr;
+            break;
+        }
+        else if (pShellOnStack == pShell)
+            break;
+    }
+
+    if (pShell == nullptr)
+        return;
+
+    // 1. Deactivate our shells on the stack before they are removed so
+    // that during the Deactivation() calls the stack is still intact.
+    for (sal_uInt16 nIndex=0; true; nIndex++)
+    {
+        SfxShell* pShellOnStack = mrBase.GetSubShell(nIndex);
+        Deactivate(pShellOnStack);
+        if (pShellOnStack == pShell)
+            break;
+    }
+
+    // 2. Remove the shells from the stack.
+    while (true)
+    {
+        SfxShell* pShellOnStack = mrBase.GetSubShell(0);
+        SAL_INFO("sd.view", __func__ << "removing shell " << pShellOnStack << " from stack");
+        mrBase.RemoveSubShell(pShellOnStack);
+        if (pShellOnStack == pShell)
+            break;
+    }
+
+    // 3. Update the stack.
+    if (mrBase.GetDispatcher() != nullptr)
+        mrBase.GetDispatcher()->Flush();
+
+    // Update the pointer to the top-most shell and set its undo manager
+    // to the one of the previous top-most shell.
+    mpTopShell = mrBase.GetSubShell(0);
+    if (mpTopShell!=nullptr && pUndoManager!=nullptr && mpTopShell->GetUndoManager()==nullptr)
+        mpTopShell->SetUndoManager(pUndoManager);
+
+#if OSL_DEBUG_LEVEL >= 2
+    SAL_INFO("sd.view", __func__ << "Sfx shell stack is:");
+    DumpSfxShellStack();
+#endif
+}
+
+void ViewShellManager::Implementation::CreateShells()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Iterate over all view shells.
+    ActiveShellList::reverse_iterator iShell;
+    for (iShell=maActiveViewShells.rbegin(); iShell!=maActiveViewShells.rend(); ++iShell)
+    {
+        // Get the list of associated sub shells.
+        SubShellList::iterator iList (maActiveSubShells.find(iShell->mpShell));
+        if (iList != maActiveSubShells.end())
+        {
+            SubShellSubList& rList (iList->second);
+
+            // Iterate over all sub shells of the current view shell.
+            for (auto & subShell : rList)
+            {
+                if (subShell.mpShell == nullptr)
+                {
+                    subShell = CreateSubShell(iShell->mpShell,subShell.mnId);
+                }
+            }
+        }
+    }
+}
+
+void ViewShellManager::Implementation::CreateTargetStack (ShellStack& rStack) const
+{
+    // Create a local stack of the shells that are to push on the shell
+    // stack.  We can thus safely create the required shells while still
+    // having a valid shell stack.
+    for (ActiveShellList::const_reverse_iterator iViewShell (maActiveViewShells.rbegin());
+         iViewShell != maActiveViewShells.rend();
+         ++iViewShell)
+    {
+        // Possibly place the form shell below the current view shell.
+        if ( ! mbFormShellAboveParent
+            && mpFormShell!=nullptr
+            && iViewShell->mpShell==mpFormShellParent)
+        {
+            rStack.push_back(mpFormShell);
+        }
+
+        // Put the view shell itself on the local stack.
+        rStack.push_back (iViewShell->mpShell);
+
+        // Possibly place the form shell above the current view shell.
+        if (mbFormShellAboveParent
+            && mpFormShell!=nullptr
+            && iViewShell->mpShell==mpFormShellParent)
+        {
+            rStack.push_back(mpFormShell);
+        }
+
+        // Add all other sub shells.
+        SubShellList::const_iterator iList (maActiveSubShells.find(iViewShell->mpShell));
+        if (iList != maActiveSubShells.end())
+        {
+            const SubShellSubList& rList (iList->second);
+            SubShellSubList::const_reverse_iterator iSubShell;
+            for (iSubShell=rList.rbegin(); iSubShell!=rList.rend(); ++iSubShell)
+                if (iSubShell->mpShell != mpFormShell)
+                    rStack.push_back(iSubShell->mpShell);
+        }
+    }
+}
+
+IMPL_LINK(ViewShellManager::Implementation, WindowEventHandler, VclWindowEvent&, rEvent, void)
+{
+        vcl::Window* pEventWindow = rEvent.GetWindow();
+
+        switch (rEvent.GetId())
+        {
+            case VclEventId::WindowGetFocus:
+            {
+                for (auto const& activeShell : maActiveViewShells)
+                {
+                    if (pEventWindow == activeShell.GetWindow())
+                    {
+                        MoveToTop(*activeShell.mpShell);
+                        break;
+                    }
+                }
+            }
+            break;
+
+            case VclEventId::WindowLoseFocus:
+                break;
+
+            case VclEventId::ObjectDying:
+                // Remember that we do not have to remove the window
+                // listener for this window.
+                for (auto & activeViewShell : maActiveViewShells)
+                {
+                    if (activeViewShell.GetWindow() == pEventWindow)
+                    {
+                        activeViewShell.mbIsListenerAddedToWindow = false;
+                        break;
+                    }
+                }
+                break;
+
+            default: break;
+        }
+}
+
+ShellDescriptor ViewShellManager::Implementation::CreateSubShell (
+    SfxShell const * pParentShell,
+    ShellId nShellId)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+    ShellDescriptor aResult;
+
+    // Look up the factories for the parent shell.
+    ::std::pair<FactoryList::iterator,FactoryList::iterator> aRange(
+        maShellFactories.equal_range(pParentShell));
+
+    // Try all factories to create the shell.
+    for (FactoryList::const_iterator iFactory=aRange.first; iFactory!=aRange.second; ++iFactory)
+    {
+        SharedShellFactory pFactory = iFactory->second;
+        if (pFactory != nullptr)
+            aResult.mpShell = pFactory->CreateShell(nShellId);
+
+        // Exit the loop when the shell has been successfully created.
+        if (aResult.mpShell != nullptr)
+        {
+            aResult.mpFactory = pFactory;
+            aResult.mnId = nShellId;
+            break;
+        }
+    }
+
+    return aResult;
+}
+
+void ViewShellManager::Implementation::DestroyViewShell (
+    ShellDescriptor& rDescriptor)
+{
+    OSL_ASSERT(rDescriptor.mpShell != nullptr);
+
+    if (rDescriptor.mbIsListenerAddedToWindow)
+    {
+        rDescriptor.mbIsListenerAddedToWindow = false;
+        vcl::Window* pWindow = rDescriptor.GetWindow();
+        if (pWindow != nullptr)
+        {
+            pWindow->RemoveEventListener(
+                LINK(this, ViewShellManager::Implementation, WindowEventHandler));
+        }
+    }
+
+    // Destroy the sub shell factories.
+    ::std::pair<FactoryList::iterator,FactoryList::iterator> aRange(
+        maShellFactories.equal_range(rDescriptor.mpShell));
+    if (aRange.first != maShellFactories.end())
+        maShellFactories.erase(aRange.first, aRange.second);
+
+    // Release the shell.
+    if (rDescriptor.mpFactory)
+        rDescriptor.mpFactory->ReleaseShell(rDescriptor.mpShell);
+}
+
+void ViewShellManager::Implementation::DestroySubShell (
+    const ShellDescriptor& rDescriptor)
+{
+    OSL_ASSERT(rDescriptor.mpFactory);
+    rDescriptor.mpFactory->ReleaseShell(rDescriptor.mpShell);
+}
+
+void ViewShellManager::Implementation::InvalidateAllSubShells (const SfxShell* pParentShell)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    SubShellList::iterator iList (maActiveSubShells.find(pParentShell));
+    if (iList != maActiveSubShells.end())
+    {
+        SubShellSubList& rList (iList->second);
+        for (auto const& shell : rList)
+            if (shell.mpShell != nullptr)
+                shell.mpShell->Invalidate();
+    }
+}
+
+void ViewShellManager::Implementation::Shutdown()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Take stacked shells from stack.
+    if ( ! maActiveViewShells.empty())
+    {
+        UpdateLock aLock (*this);
+
+        while ( ! maActiveViewShells.empty())
+        {
+            SfxShell* pShell = maActiveViewShells.front().mpShell;
+            if (pShell != nullptr)
+            {
+                ViewShell* pViewShell = dynamic_cast<ViewShell*>(pShell);
+                if (pViewShell != nullptr)
+                    DeactivateViewShell(*pViewShell);
+                else
+                    DeactivateShell(*pShell);
+            }
+            else
+            {
+                SAL_WARN("sd.view",
+                    "ViewShellManager::Implementation::Shutdown(): empty active shell descriptor");
+                maActiveViewShells.pop_front();
+            }
+        }
+    }
+    mrBase.RemoveSubShell ();
+
+    maShellFactories.clear();
+}
+
+#if OSL_DEBUG_LEVEL >= 2
+void ViewShellManager::Implementation::DumpShellStack (const ShellStack& rStack)
+{
+    ShellStack::const_reverse_iterator iEntry;
+    for (iEntry=rStack.rbegin(); iEntry!=rStack.rend(); ++iEntry)
+        if (*iEntry != NULL)
+            SAL_INFO("sd.view", __func__ << ":    " <<
+                *iEntry << " : " <<
+                (*iEntry)->GetName());
+        else
+            SAL_INFO("sd.view", __func__ << "     null");
+}
+
+void ViewShellManager::Implementation::DumpSfxShellStack()
+{
+    ShellStack aSfxShellStack;
+    sal_uInt16 nIndex (0);
+    while (mrBase.GetSubShell(nIndex)!=NULL)
+        ++nIndex;
+    aSfxShellStack.reserve(nIndex);
+    while (nIndex-- > 0)
+        aSfxShellStack.push_back(mrBase.GetSubShell(nIndex));
+    DumpShellStack(aSfxShellStack);
+}
+#endif
+
+void ViewShellManager::Implementation::Deactivate (SfxShell* pShell)
+{
+    OSL_ASSERT(pShell!=nullptr);
+
+    // We have to end a text edit for view shells that are to be taken from
+    // the shell stack.
+    ViewShell* pViewShell = dynamic_cast<ViewShell*>(pShell);
+    if (pViewShell != nullptr)
+    {
+        sd::View* pView = pViewShell->GetView();
+        if (pView!=nullptr && pView->IsTextEdit())
+        {
+            pView->SdrEndTextEdit();
+            pView->UnmarkAll();
+            pViewShell->GetViewFrame()->GetDispatcher()->Execute(
+                SID_OBJECT_SELECT,
+                SfxCallMode::ASYNCHRON);
+        }
+    }
+
+    // Now we can deactivate the shell.
+    pShell->Deactivate(true);
+}
+
+void ViewShellManager::Implementation::SetFormShell (
+    const ViewShell* pFormShellParent,
+    FmFormShell* pFormShell,
+    bool bFormShellAboveParent)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    mpFormShellParent = pFormShellParent;
+    mpFormShell = pFormShell;
+    mbFormShellAboveParent = bFormShellAboveParent;
+}
+
+namespace {
+
+ShellDescriptor::ShellDescriptor()
+    : mpShell(nullptr),
+      mnId(ToolbarId::None),
+      mbIsListenerAddedToWindow(false)
+{
+}
+
+ShellDescriptor::ShellDescriptor (
+    ShellId nId)
+    : mpShell(nullptr),
+      mnId(nId),
+      mbIsListenerAddedToWindow(false)
+{
+}
+
+vcl::Window* ShellDescriptor::GetWindow() const
+{
+    ViewShell* pViewShell = dynamic_cast<ViewShell*>(mpShell);
+    if (pViewShell != nullptr)
+        return pViewShell->GetActiveWindow();
+    else
+        return nullptr;
+}
+
+} // end of anonymous namespace
+
+} // end of namespace sd
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */