Source/platform/scroll/FramelessScrollView.h

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#ifndef FramelessScrollView_h
#define FramelessScrollView_h

#include "platform/PlatformExport.h"
#include "platform/scroll/ScrollView.h"

namespace WebCore {

class FramelessScrollViewClient;
class PlatformGestureEvent;
class PlatformKeyboardEvent;
class PlatformMouseEvent;
class PlatformTouchEvent;
class PlatformWheelEvent;

// A FramelessScrollView is a ScrollView that can be used to render custom
// content, which does not have an associated Frame.
//
// NOTE: It may be better to just develop a custom subclass of Widget that
// can have scroll bars for this instead of trying to reuse ScrollView.
//
class PLATFORM_EXPORT FramelessScrollView : public ScrollView {
public:
    FramelessScrollView() : m_client(0) { }
    ~FramelessScrollView();

    FramelessScrollViewClient* client() const { return m_client; }
    void setClient(FramelessScrollViewClient* client) { m_client = client; }

    // Event handlers that subclasses must implement.
    virtual bool handleMouseDownEvent(const PlatformMouseEvent&) = 0;
    virtual bool handleMouseMoveEvent(const PlatformMouseEvent&) = 0;
    virtual bool handleMouseReleaseEvent(const PlatformMouseEvent&) = 0;
    virtual bool handleWheelEvent(const PlatformWheelEvent&) = 0;
    virtual bool handleKeyEvent(const PlatformKeyboardEvent&) = 0;
    virtual bool handleTouchEvent(const PlatformTouchEvent&) = 0;
    virtual bool handleGestureEvent(const PlatformGestureEvent&) = 0;

    // ScrollableArea public methods:
    virtual void invalidateScrollbarRect(Scrollbar*, const IntRect&) OVERRIDE;
    virtual bool isActive() const OVERRIDE;
    virtual ScrollableArea* enclosingScrollableArea() const OVERRIDE;
    virtual bool scrollbarsCanBeActive() const OVERRIDE;
    virtual IntRect scrollableAreaBoundingBox() const OVERRIDE;

    // Widget public methods:
    virtual void invalidateRect(const IntRect&);

    // ScrollView public methods:
    virtual HostWindow* hostWindow() const;
    virtual IntRect windowClipRect(bool clipToContents = true) const;

protected:
    // ScrollView protected methods:
    virtual void paintContents(GraphicsContext*, const IntRect&);
    virtual void contentsResized();
    virtual void scrollbarExistenceDidChange();

private:
    FramelessScrollViewClient* m_client;
};

} // namespace WebCore

#endif