third_party/WebKit/public/platform/WebScrollbarThemePainter.h

   1 /*
   2  * Copyright (C) 2012 Google 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  *
   8  * 1.  Redistributions of source code must retain the above copyright
   9  *     notice, this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright
  11  *     notice, this list of conditions and the following disclaimer in the
  12  *     documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  17  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  18  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  20  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  21  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef WebScrollbarThemePainter_h
  27 #define WebScrollbarThemePainter_h
  28
  29 #include "public/platform/WebCanvas.h"
  30 #include "public/platform/WebPrivatePtr.h"
  31
  32 namespace blink {
  33
  34 class ScrollbarTheme;
  35 class Scrollbar;
  36 class WebScrollbar;
  37 struct WebRect;
  38
  39 class WebScrollbarThemePainter {
  40 public:
  41     WebScrollbarThemePainter() : m_theme(0) { }
  42     WebScrollbarThemePainter(const WebScrollbarThemePainter& painter) { assign(painter); }
  43     virtual ~WebScrollbarThemePainter()
  44     {
  45         reset();
  46     }
  47     WebScrollbarThemePainter& operator=(const WebScrollbarThemePainter& painter)
  48     {
  49         assign(painter);
  50         return *this;
  51     }
  52
  53     BLINK_PLATFORM_EXPORT void assign(const WebScrollbarThemePainter&);
  54     BLINK_PLATFORM_EXPORT void reset();
  55
  56     BLINK_PLATFORM_EXPORT void paintScrollbarBackground(WebCanvas*, const WebRect&);
  57     BLINK_PLATFORM_EXPORT void paintTrackBackground(WebCanvas*, const WebRect&);
  58     BLINK_PLATFORM_EXPORT void paintBackTrackPart(WebCanvas*, const WebRect&);
  59     BLINK_PLATFORM_EXPORT void paintForwardTrackPart(WebCanvas*, const WebRect&);
  60     BLINK_PLATFORM_EXPORT void paintBackButtonStart(WebCanvas*, const WebRect&);
  61     BLINK_PLATFORM_EXPORT void paintBackButtonEnd(WebCanvas*, const WebRect&);
  62     BLINK_PLATFORM_EXPORT void paintForwardButtonStart(WebCanvas*, const WebRect&);
  63     BLINK_PLATFORM_EXPORT void paintForwardButtonEnd(WebCanvas*, const WebRect&);
  64     BLINK_PLATFORM_EXPORT void paintTickmarks(WebCanvas*, const WebRect&);
  65     BLINK_PLATFORM_EXPORT void paintThumb(WebCanvas*, const WebRect&);
  66
  67 #if INSIDE_BLINK
  68     BLINK_PLATFORM_EXPORT WebScrollbarThemePainter(ScrollbarTheme*, Scrollbar*);
  69 #endif
  70
  71 private:
  72     // The theme is not owned by this class. It is assumed that the theme is a
  73     // static pointer and its lifetime is essentially infinite. The functions
  74     // called from the painter may not be thread-safe, so all calls must be made
  75     // from the same thread that it is created on.
  76     ScrollbarTheme* m_theme;
  77
  78     // It is assumed that the constructor of this paint object is responsible
  79     // for the lifetime of this scrollbar. The painter has to use the real
  80     // scrollbar (and not a WebScrollbar wrapper) due to static_casts for
  81     // LayoutScrollbar and pointer-based HashMap lookups for Lion scrollbars.
  82     WebPrivatePtr<Scrollbar> m_scrollbar;
  83 };
  84
  85 } // namespace blink
  86
  87 #endif