Source/WebCore/platform/ScrollbarThemeComposite.h

/*
 * Copyright (C) 2008 Apple Inc. All Rights Reserved.
 *
 * 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 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 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. 
 */

#pragma once

#include "ScrollbarTheme.h"

#if PLATFORM(COCOA)
OBJC_CLASS NSScrollerImp;
#endif

namespace WebCore {

class ScrollbarThemeComposite : public ScrollbarTheme {
public:
    // Implement ScrollbarTheme interface
    bool paint(Scrollbar&, GraphicsContext&, const IntRect& damageRect) override;
    ScrollbarPart hitTest(Scrollbar&, const IntPoint&) override;
    void invalidatePart(Scrollbar&, ScrollbarPart) override;
    int thumbPosition(Scrollbar&) override;
    int thumbLength(Scrollbar&) override;
    int trackPosition(Scrollbar&) override;
    int trackLength(Scrollbar&) override;
    void paintOverhangAreas(ScrollView&, GraphicsContext&, const IntRect& horizontalOverhangArea, const IntRect& verticalOverhangArea, const IntRect& dirtyRect) override;

    virtual bool hasButtons(Scrollbar&) = 0;
    virtual bool hasThumb(Scrollbar&) = 0;

    virtual IntRect backButtonRect(Scrollbar&, ScrollbarPart, bool painting = false) = 0;
    virtual IntRect forwardButtonRect(Scrollbar&, ScrollbarPart, bool painting = false) = 0;
    virtual IntRect trackRect(Scrollbar&, bool painting = false) = 0;
    virtual IntRect thumbRect(Scrollbar&);

    virtual void splitTrack(Scrollbar&, const IntRect& track, IntRect& startTrack, IntRect& thumb, IntRect& endTrack);
    
    virtual int minimumThumbLength(Scrollbar&);

    virtual void willPaintScrollbar(GraphicsContext&, Scrollbar&) { }
    virtual void didPaintScrollbar(GraphicsContext&, Scrollbar&) { }

    virtual void paintScrollbarBackground(GraphicsContext&, Scrollbar&) { }
    virtual void paintTrackBackground(GraphicsContext&, Scrollbar&, const IntRect&) { }
    virtual void paintTrackPiece(GraphicsContext&, Scrollbar&, const IntRect&, ScrollbarPart) { }
    virtual void paintButton(GraphicsContext&, Scrollbar&, const IntRect&, ScrollbarPart) { }
    virtual void paintThumb(GraphicsContext&, Scrollbar&, const IntRect&) { }

    virtual IntRect constrainTrackRectToTrackPieces(Scrollbar&, const IntRect& rect) { return rect; }
};

}