1/*
2 * Copyright (C) 2008, 2009 Apple Inc. All Rights Reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef RenderScrollbar_h
27#define RenderScrollbar_h
28
29#include "RenderStyleConstants.h"
30#include "Scrollbar.h"
31#include <wtf/HashMap.h>
32
33namespace WebCore {
34
35class Frame;
36class Node;
37class RenderBox;
38class RenderScrollbarPart;
39class RenderStyle;
40
41class RenderScrollbar : public Scrollbar {
42protected:
43    RenderScrollbar(ScrollableArea*, ScrollbarOrientation, Node*, Frame*);
44
45public:
46    friend class Scrollbar;
47    static PassRefPtr<Scrollbar> createCustomScrollbar(ScrollableArea*, ScrollbarOrientation, Node*, Frame* owningFrame = 0);
48    virtual ~RenderScrollbar();
49
50    RenderBox* owningRenderer() const;
51
52    void paintPart(GraphicsContext*, ScrollbarPart, const IntRect&);
53
54    IntRect buttonRect(ScrollbarPart);
55    IntRect trackRect(int startLength, int endLength);
56    IntRect trackPieceRectWithMargins(ScrollbarPart, const IntRect&);
57
58    int minimumThumbLength();
59
60    virtual bool isOverlayScrollbar() const { return false; }
61
62private:
63    virtual void setParent(ScrollView*);
64    virtual void setEnabled(bool);
65
66    virtual void paint(GraphicsContext*, const IntRect& damageRect);
67
68    virtual void setHoveredPart(ScrollbarPart);
69    virtual void setPressedPart(ScrollbarPart);
70
71    virtual void styleChanged();
72
73    virtual bool isCustomScrollbar() const { return true; }
74
75    void updateScrollbarParts(bool destroy = false);
76
77    PassRefPtr<RenderStyle> getScrollbarPseudoStyle(ScrollbarPart, PseudoId);
78    void updateScrollbarPart(ScrollbarPart, bool destroy = false);
79
80    // This Scrollbar(Widget) may outlive the DOM which created it (during tear down),
81    // so we keep a reference to the Node which caused this custom scrollbar creation.
82    // This will not create a reference cycle as the Widget tree is owned by our containing
83    // FrameView which this Node pointer can in no way keep alive. See webkit bug 80610.
84    RefPtr<Node> m_owner;
85
86    Frame* m_owningFrame;
87    HashMap<unsigned, RenderScrollbarPart*> m_parts;
88};
89
90inline RenderScrollbar* toRenderScrollbar(ScrollbarThemeClient* scrollbar)
91{
92    ASSERT_WITH_SECURITY_IMPLICATION(!scrollbar || scrollbar->isCustomScrollbar());
93    return static_cast<RenderScrollbar*>(scrollbar);
94}
95
96// This will catch anyone doing an unnecessary cast.
97void toRenderScrollbar(const RenderScrollbar*);
98
99} // namespace WebCore
100
101#endif // RenderScrollbar_h
102