1 files changed, 90 insertions, 0 deletions
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsVisibleAreaManager.hxx b/sd/source/ui/slidesorter/inc/controller/SlsVisibleAreaManager.hxx
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+++ b/sd/source/ui/slidesorter/inc/controller/SlsVisibleAreaManager.hxx
@@ -0,0 +1,90 @@
+/* -*- 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 <model/SlsSharedPageDescriptor.hxx>
+#include <optional>
+#include <tools/gen.hxx>
+#include <vector>
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::controller
+{
+/** Manage requests for scrolling page objects into view.
+*/
+class VisibleAreaManager
+{
+public:
+    explicit VisibleAreaManager(SlideSorter& rSlideSorter);
+    ~VisibleAreaManager();
+    VisibleAreaManager(const VisibleAreaManager&) = delete;
+    VisibleAreaManager& operator=(const VisibleAreaManager&) = delete;
+
+    void ActivateCurrentSlideTracking();
+    void DeactivateCurrentSlideTracking();
+    bool IsCurrentSlideTrackingActive() const { return mbIsCurrentSlideTrackingActive; }
+
+    /** Request the current slide to be moved into the visible area.
+        This request is only obeyed when the current slide tracking is
+        active.
+        @see ActivateCurrentSlideTracking() and DeactivateCurrentSlideTracking()
+    */
+    void RequestCurrentSlideVisible();
+
+    /** Request to make the specified page object visible.
+    */
+    void RequestVisible(const model::SharedPageDescriptor& rpDescriptor, const bool bForce = false);
+
+    /** Temporarily disable the update of the visible area.
+    */
+    class TemporaryDisabler
+    {
+    public:
+        explicit TemporaryDisabler(SlideSorter const& rSlideSorter);
+        ~TemporaryDisabler();
+
+    private:
+        VisibleAreaManager& mrVisibleAreaManager;
+    };
+
+private:
+    SlideSorter& mrSlideSorter;
+
+    /** List of rectangle that someone wants to be moved into the visible
+        area.
+        Cleared on every call to ForgetVisibleRequests() and MakeVisible().
+    */
+    ::std::vector<::tools::Rectangle> maVisibleRequests;
+
+    Point maRequestedVisibleTopLeft;
+    bool mbIsCurrentSlideTrackingActive;
+    int mnDisableCount;
+
+    void MakeVisible();
+    ::std::optional<Point> GetRequestedTopLeft() const;
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */