Home | History | Annotate | Download | only in rendering 
      1 /*
      2  * Copyright (C) 2008 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 RenderScrollbarPart_h
     27 #define RenderScrollbarPart_h
     28 
     29 #include "core/platform/ScrollTypes.h"
     30 #include "core/rendering/RenderBlock.h"
     31 
     32 namespace WebCore {
     33 
     34 class RenderScrollbar;
     35 
     36 class RenderScrollbarPart FINAL : public RenderBlock {
     37 public:
     38     static RenderScrollbarPart* createAnonymous(Document*, RenderScrollbar* = 0, ScrollbarPart = NoPart);
     39 
     40     virtual ~RenderScrollbarPart();
     41 
     42     virtual const char* renderName() const { return "RenderScrollbarPart"; }
     43 
     44     virtual bool requiresLayer() const { return false; }
     45 
     46     virtual void layout();
     47 
     48     void paintIntoRect(GraphicsContext*, const LayoutPoint&, const LayoutRect&);
     49 
     50     // Scrollbar parts needs to be rendered at device pixel boundaries.
     51     virtual LayoutUnit marginTop() const OVERRIDE { ASSERT(isIntegerValue(m_marginBox.top())); return m_marginBox.top(); }
     52     virtual LayoutUnit marginBottom() const OVERRIDE { ASSERT(isIntegerValue(m_marginBox.bottom())); return m_marginBox.bottom(); }
     53     virtual LayoutUnit marginLeft() const OVERRIDE { ASSERT(isIntegerValue(m_marginBox.left())); return m_marginBox.left(); }
     54     virtual LayoutUnit marginRight() const OVERRIDE { ASSERT(isIntegerValue(m_marginBox.right())); return m_marginBox.right(); }
     55 
     56     virtual bool isRenderScrollbarPart() const { return true; }
     57     RenderObject* rendererOwningScrollbar() const;
     58 
     59 protected:
     60     virtual void styleWillChange(StyleDifference diff, const RenderStyle* newStyle);
     61     virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle);
     62     virtual void imageChanged(WrappedImagePtr, const IntRect* = 0);
     63 
     64 private:
     65     RenderScrollbarPart(RenderScrollbar*, ScrollbarPart);
     66 
     67     virtual void computePreferredLogicalWidths();
     68 
     69     void layoutHorizontalPart();
     70     void layoutVerticalPart();
     71 
     72     void computeScrollbarWidth();
     73     void computeScrollbarHeight();
     74 
     75     RenderScrollbar* m_scrollbar;
     76     ScrollbarPart m_part;
     77 };
     78 
     79 inline RenderScrollbarPart* toRenderScrollbarPart(RenderObject* object)
     80 {
     81     ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isRenderScrollbarPart());
     82     return static_cast<RenderScrollbarPart*>(object);
     83 }
     84 
     85 inline const RenderScrollbarPart* toRenderScrollbarPart(const RenderObject* object)
     86 {
     87     ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isRenderScrollbarPart());
     88     return static_cast<const RenderScrollbarPart*>(object);
     89 }
     90 
     91 // This will catch anyone doing an unnecessary cast.
     92 void toRenderScrollbarPart(const RenderScrollbarPart*);
     93 
     94 } // namespace WebCore
     95 
     96 #endif // RenderScrollbarPart_h
     97