Merge FrameView and ScrollView.

Source/platform/scroll/ScrollView.h

-/*
- * Copyright (C) 2004, 2006, 2007, 2008 Apple Inc. All rights reserved.
- * Copyright (C) 2009 Holger Hans Peter Freyther
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
- * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef ScrollView_h
-#define ScrollView_h
-
-#include "platform/PlatformExport.h"
-#include "platform/Widget.h"
-#include "platform/geometry/IntRect.h"
-#include "platform/scroll/ScrollTypes.h"
-#include "platform/scroll/ScrollableArea.h"
-#include "platform/scroll/Scrollbar.h"
-
-#include "wtf/HashSet.h"
-#include "wtf/TemporaryChange.h"
-
-namespace blink {
-
-class Scrollbar;
-
-class PLATFORM_EXPORT ScrollView : public Widget, public ScrollableArea {
-public:
-    virtual ~ScrollView();
-
-    // ScrollableArea functions.
-    virtual int scrollSize(ScrollbarOrientation) const override;
-    virtual void setScrollOffset(const IntPoint&) override;
-    virtual void setScrollOffset(const DoublePoint&) override;
-    virtual bool isScrollCornerVisible() const override;
-    virtual void scrollbarStyleChanged() override;
-    virtual bool userInputScrollable(ScrollbarOrientation) const override;
-    virtual bool shouldPlaceVerticalScrollbarOnLeft() const override;
-
-    virtual void notifyPageThatContentAreaWillPaint() const;
-
-    // The window that hosts the ScrollView. The ScrollView will communicate scrolls and repaints to the
-    // host window in the window's coordinate space.
-    virtual HostWindow* hostWindow() const = 0;
-
-    // Returns a clip rect in host window coordinates. Used to clip the blit on a scroll.
-    virtual IntRect windowClipRect(IncludeScrollbarsInRect = ExcludeScrollbars) const = 0;
-
-    // Functions for child manipulation and inspection.
-    const HashSet<RefPtr<Widget> >* children() const { return &m_children; }
-    virtual void addChild(PassRefPtr<Widget>);
-    virtual void removeChild(Widget*);
-
-    // If the scroll view does not use a native widget, then it will have cross-platform Scrollbars. These functions
-    // can be used to obtain those scrollbars.
-    virtual Scrollbar* horizontalScrollbar() const override { return m_horizontalScrollbar.get(); }
-    virtual Scrollbar* verticalScrollbar() const override { return m_verticalScrollbar.get(); }
-    virtual bool isScrollViewScrollbar(const Widget* child) const override { return horizontalScrollbar() == child || verticalScrollbar() == child; }
-
-    void positionScrollbarLayers();
-
-    // Functions for setting and retrieving the scrolling mode in each axis (horizontal/vertical). The mode has values of
-    // AlwaysOff, AlwaysOn, and Auto. AlwaysOff means never show a scrollbar, AlwaysOn means always show a scrollbar.
-    // Auto means show a scrollbar only when one is needed.
-    // Note that for platforms with native widgets, these modes are considered advisory. In other words the underlying native
-    // widget may choose not to honor the requested modes.
-    void setScrollbarModes(ScrollbarMode horizontalMode, ScrollbarMode verticalMode, bool horizontalLock = false, bool verticalLock = false);
-    void setHorizontalScrollbarMode(ScrollbarMode mode, bool lock = false) { setScrollbarModes(mode, verticalScrollbarMode(), lock, verticalScrollbarLock()); }
-    void setVerticalScrollbarMode(ScrollbarMode mode, bool lock = false) { setScrollbarModes(horizontalScrollbarMode(), mode, horizontalScrollbarLock(), lock); };
-    void scrollbarModes(ScrollbarMode& horizontalMode, ScrollbarMode& verticalMode) const;
-    ScrollbarMode horizontalScrollbarMode() const { ScrollbarMode horizontal, vertical; scrollbarModes(horizontal, vertical); return horizontal; }
-    ScrollbarMode verticalScrollbarMode() const { ScrollbarMode horizontal, vertical; scrollbarModes(horizontal, vertical); return vertical; }
-
-    void setHorizontalScrollbarLock(bool lock = true) { m_horizontalScrollbarLock = lock; }
-    bool horizontalScrollbarLock() const { return m_horizontalScrollbarLock; }
-    void setVerticalScrollbarLock(bool lock = true) { m_verticalScrollbarLock = lock; }
-    bool verticalScrollbarLock() const { return m_verticalScrollbarLock; }
-
-    void setScrollingModesLock(bool lock = true) { m_horizontalScrollbarLock = m_verticalScrollbarLock = lock; }
-
-    virtual void setCanHaveScrollbars(bool);
-    bool canHaveScrollbars() const { return horizontalScrollbarMode() != ScrollbarAlwaysOff || verticalScrollbarMode() != ScrollbarAlwaysOff; }
-
-    // By default, paint events are clipped to the visible area.  If set to
-    // false, paint events are no longer clipped.
-    bool clipsPaintInvalidations() const { return m_clipsRepaints; }
-    void setClipsRepaints(bool);
-
-    // Overridden by FrameView to create custom CSS scrollbars if applicable.
-    virtual PassRefPtr<Scrollbar> createScrollbar(ScrollbarOrientation);
-
-    // The visible content rect has a location that is the scrolled offset of the document. The width and height are the viewport width
-    // and height. By default the scrollbars themselves are excluded from this rectangle, but an optional boolean argument allows them to be
-    // included.
-    virtual IntRect visibleContentRect(IncludeScrollbarsInRect = ExcludeScrollbars) const override;
-    IntSize visibleSize() const { return visibleContentRect().size(); }
-
-    // visibleContentRect().size() is computed from unscaledVisibleContentSize() divided by the value of visibleContentScaleFactor.
-    // For the main frame, visibleContentScaleFactor is equal to the page's pageScaleFactor; it's 1 otherwise.
-    IntSize unscaledVisibleContentSize(IncludeScrollbarsInRect = ExcludeScrollbars) const;
-    virtual float visibleContentScaleFactor() const { return 1; }
-
-    // Offset used to convert incoming input events while emulating device metics.
-    virtual IntSize inputEventsOffsetForEmulation() const { return IntSize(); }
-
-    // Scale used to convert incoming input events. Usually the same as visibleContentScaleFactor(), unless specifically changed.
-    virtual float inputEventsScaleFactor() const { return visibleContentScaleFactor(); }
-
-    // Functions for getting/setting the size of the document contained inside the ScrollView (as an IntSize or as individual width and height
-    // values).
-    virtual IntSize contentsSize() const override; // Always at least as big as the visibleWidth()/visibleHeight().
-    int contentsWidth() const { return contentsSize().width(); }
-    int contentsHeight() const { return contentsSize().height(); }
-    virtual void setContentsSize(const IntSize&);
-
-    // Functions for querying the current scrolled position (both as a point, a size, or as individual X and Y values).
-    // FIXME: Remove the IntPoint version. crbug.com/414283.
-    virtual IntPoint scrollPosition() const override { return visibleContentRect().location(); }
-    virtual DoublePoint scrollPositionDouble() const override { return m_scrollPosition; }
-    IntSize scrollOffset() const { return toIntSize(visibleContentRect().location()); } // Gets the scrolled position as an IntSize. Convenient for adding to other sizes.
-    DoubleSize pendingScrollDelta() const { return m_pendingScrollDelta; }
-    virtual IntPoint maximumScrollPosition() const override; // The maximum position we can be scrolled to.
-    virtual IntPoint minimumScrollPosition() const override; // The minimum position we can be scrolled to.
-    // Adjust the passed in scroll position to keep it between the minimum and maximum positions.
-    IntPoint adjustScrollPositionWithinRange(const IntPoint&) const;
-    DoublePoint adjustScrollPositionWithinRange(const DoublePoint&) const;
-    double scrollX() const { return scrollPositionDouble().x(); }
-    double scrollY() const { return scrollPositionDouble().y(); }
-
-    virtual IntSize overhangAmount() const override;
-
-    void cacheCurrentScrollPosition() { m_cachedScrollPosition = scrollPositionDouble(); }
-    DoublePoint cachedScrollPosition() const { return m_cachedScrollPosition; }
-
-    // Functions for scrolling the view.
-    virtual void setScrollPosition(const IntPoint&, ScrollBehavior = ScrollBehaviorInstant);
-    void scrollBy(const IntSize& s, ScrollBehavior behavior = ScrollBehaviorInstant)
-    {
-        return setScrollPosition(scrollPosition() + s, behavior);
-    }
-
-    bool scroll(ScrollDirection, ScrollGranularity);
-
-    // Scroll the actual contents of the view (either blitting or invalidating as needed).
-    void scrollContents(const IntSize& scrollDelta);
-
-    // This gives us a means of blocking painting on our scrollbars until the first layout has occurred.
-    void setScrollbarsSuppressed(bool suppressed, bool repaintOnUnsuppress = false);
-    bool scrollbarsSuppressed() const { return m_scrollbarsSuppressed; }
-
-    IntPoint rootViewToContents(const IntPoint&) const;
-    IntPoint contentsToRootView(const IntPoint&) const;
-    IntRect rootViewToContents(const IntRect&) const;
-    IntRect contentsToRootView(const IntRect&) const;
-
-    // Event coordinates are assumed to be in the coordinate space of a window that contains
-    // the entire widget hierarchy. It is up to the platform to decide what the precise definition
-    // of containing window is. (For example on Mac it is the containing NSWindow.)
-    IntPoint windowToContents(const IntPoint&) const;
-    FloatPoint windowToContents(const FloatPoint&) const;
-    IntPoint contentsToWindow(const IntPoint&) const;
-    IntRect windowToContents(const IntRect&) const;
-    IntRect contentsToWindow(const IntRect&) const;
-
-    // Functions for converting to screen coordinates.
-    IntRect contentsToScreen(const IntRect&) const;
-
-    // These functions are used to enable scrollbars to avoid window resizer controls that overlap the scroll view. This happens on Mac
-    // for example.
-    virtual IntRect windowResizerRect() const { return IntRect(); }
-    bool containsScrollbarsAvoidingResizer() const;
-    void adjustScrollbarsAvoidingResizerCount(int overlapDelta);
-    void windowResizerRectChanged();
-
-    virtual void setParent(Widget*) override; // Overridden to update the overlapping scrollbar count.
-
-    // Called when our frame rect changes (or the rect/scroll position of an ancestor changes).
-    virtual void frameRectsChanged() override;
-
-    // Widget override to update our scrollbars and notify our contents of the resize.
-    virtual void setFrameRect(const IntRect&) override;
-
-    // For platforms that need to hit test scrollbars from within the engine's event handlers (like Win32).
-    Scrollbar* scrollbarAtWindowPoint(const IntPoint& windowPoint);
-    Scrollbar* scrollbarAtViewPoint(const IntPoint& viewPoint);
-
-    virtual IntPoint convertChildToSelf(const Widget* child, const IntPoint& point) const override
-    {
-        IntPoint newPoint = point;
-        if (!isScrollViewScrollbar(child))
-            newPoint = point - scrollOffset();
-        newPoint.moveBy(child->location());
-        return newPoint;
-    }
-
-    virtual IntPoint convertSelfToChild(const Widget* child, const IntPoint& point) const override
-    {
-        IntPoint newPoint = point;
-        if (!isScrollViewScrollbar(child))
-            newPoint = point + scrollOffset();
-        newPoint.moveBy(-child->location());
-        return newPoint;
-    }
-
-    // Widget override. Handles painting of the contents of the view as well as the scrollbars.
-    virtual void paint(GraphicsContext*, const IntRect&) override;
-    void paintScrollbars(GraphicsContext*, const IntRect&);
-
-    // Widget overrides to ensure that our children's visibility status is kept up to date when we get shown and hidden.
-    virtual void show() override;
-    virtual void hide() override;
-    virtual void setParentVisible(bool) override;
-
-    // Pan scrolling.
-    static const int noPanScrollRadius = 15;
-    void addPanScrollIcon(const IntPoint&);
-    void removePanScrollIcon();
-    void paintPanScrollIcon(GraphicsContext*);
-
-    virtual bool isPointInScrollbarCorner(const IntPoint&);
-    virtual bool scrollbarCornerPresent() const;
-    virtual IntRect scrollCornerRect() const override;
-    virtual void paintScrollCorner(GraphicsContext*, const IntRect& cornerRect);
-    virtual void paintScrollbar(GraphicsContext*, Scrollbar*, const IntRect&);
-
-    virtual IntRect convertFromScrollbarToContainingView(const Scrollbar*, const IntRect&) const override;
-    virtual IntRect convertFromContainingViewToScrollbar(const Scrollbar*, const IntRect&) const override;
-    virtual IntPoint convertFromScrollbarToContainingView(const Scrollbar*, const IntPoint&) const override;
-    virtual IntPoint convertFromContainingViewToScrollbar(const Scrollbar*, const IntPoint&) const override;
-
-    void calculateAndPaintOverhangAreas(GraphicsContext*, const IntRect& dirtyRect);
-    void calculateAndPaintOverhangBackground(GraphicsContext*, const IntRect& dirtyRect);
-
-    virtual bool isScrollView() const override FINAL { return true; }
-
-protected:
-    ScrollView();
-
-    // NOTE: This should only be called by the overriden setScrollOffset from ScrollableArea.
-    virtual void scrollTo(const DoublePoint& newPosition);
-
-    virtual void contentRectangleForPaintInvalidation(const IntRect&);
-    virtual void paintContents(GraphicsContext*, const IntRect& damageRect) = 0;
-
-    virtual void paintOverhangAreas(GraphicsContext*, const IntRect& horizontalOverhangArea, const IntRect& verticalOverhangArea, const IntRect& dirtyRect);
-
-    virtual void scrollbarExistenceDidChange() = 0;
-    // These functions are used to create/destroy scrollbars.
-    void setHasHorizontalScrollbar(bool);
-    void setHasVerticalScrollbar(bool);
-
-    virtual void updateScrollCorner();
-    virtual void invalidateScrollCornerRect(const IntRect&) override;
-
-    void scrollContentsIfNeeded();
-    // Scroll the content by via the compositor.
-    virtual bool scrollContentsFastPath(const IntSize& scrollDelta) { return true; }
-    // Scroll the content by invalidating everything.
-    virtual void scrollContentsSlowPath(const IntRect& updateRect);
-
-    void setScrollOrigin(const IntPoint&, bool updatePositionAtAll, bool updatePositionSynchronously);
-
-    // Subclassed by FrameView to check the writing-mode of the document.
-    virtual bool isVerticalDocument() const { return true; }
-    virtual bool isFlippedDocument() const { return false; }
-
-    enum ComputeScrollbarExistenceOption {
-        FirstPass,
-        Incremental
-    };
-    void computeScrollbarExistence(bool& newHasHorizontalScrollbar, bool& newHasVerticalScrollbar, const IntSize& docSize, ComputeScrollbarExistenceOption = FirstPass) const;
-    void updateScrollbarGeometry();
-    IntRect adjustScrollbarRectForResizer(const IntRect&, Scrollbar*);
-
-    // Called to update the scrollbars to accurately reflect the state of the view.
-    void updateScrollbars(const IntSize& desiredOffset);
-
-    IntSize excludeScrollbars(const IntSize&) const;
-
-    class InUpdateScrollbarsScope {
-    public:
-        explicit InUpdateScrollbarsScope(ScrollView* view)
-            : m_scope(view->m_inUpdateScrollbars, true)
-        { }
-    private:
-        TemporaryChange<bool> m_scope;
-    };
-
-    virtual bool scrollbarsDisabled() const { return false; }
-
-private:
-    bool adjustScrollbarExistence(ComputeScrollbarExistenceOption = FirstPass);
-    void adjustScrollbarOpacity();
-    // FIXME(bokan): setScrollOffset, setScrollPosition, scrollTo, scrollToOffsetWithoutAnimation,
-    // notifyScrollPositionChanged...there's too many ways to scroll this class. This needs
-    // some cleanup.
-    void setScrollOffsetFromUpdateScrollbars(const IntSize&);
-
-    RefPtr<Scrollbar> m_horizontalScrollbar;
-    RefPtr<Scrollbar> m_verticalScrollbar;
-    ScrollbarMode m_horizontalScrollbarMode;
-    ScrollbarMode m_verticalScrollbarMode;
-
-    bool m_horizontalScrollbarLock;
-    bool m_verticalScrollbarLock;
-
-    HashSet<RefPtr<Widget> > m_children;
-
-    DoubleSize m_pendingScrollDelta;
-    DoublePoint m_scrollPosition;
-    DoublePoint m_cachedScrollPosition;
-    IntSize m_contentsSize;
-
-    int m_scrollbarsAvoidingResizer;
-    bool m_scrollbarsSuppressed;
-
-    bool m_inUpdateScrollbars;
-
-    IntPoint m_panScrollIconPoint;
-    bool m_drawPanScrollIcon;
-
-    bool m_clipsRepaints;
-
-    void init();
-    void destroy();
-
-    IntRect rectToCopyOnScroll() const;
-
-    void calculateOverhangAreasForPainting(IntRect& horizontalOverhangRect, IntRect& verticalOverhangRect);
-    void updateOverhangAreas();
-}; // class ScrollView
-
-DEFINE_TYPE_CASTS(ScrollView, Widget, widget, widget->isScrollView(), widget.isScrollView());
-
-} // namespace blink
-
-#endif // ScrollView_h