third_party/WebKit/Source/core/layout/LayoutScrollbarTheme.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.
 */

#ifndef LayoutScrollbarTheme_h
#define LayoutScrollbarTheme_h

#include "platform/scroll/ScrollbarTheme.h"

namespace blink {

class WebMouseEvent;

class LayoutScrollbarTheme final : public ScrollbarTheme {
 public:
  ~LayoutScrollbarTheme() override {}

  int scrollbarThickness(ScrollbarControlSize controlSize) override {
    return ScrollbarTheme::theme().scrollbarThickness(controlSize);
  }

  WebScrollbarButtonsPlacement buttonsPlacement() const override {
    return ScrollbarTheme::theme().buttonsPlacement();
  }

  void paintScrollCorner(GraphicsContext&,
                         const DisplayItemClient&,
                         const IntRect& cornerRect) override;

  bool shouldCenterOnThumb(const ScrollbarThemeClient& scrollbar,
                           const WebMouseEvent& event) override {
    return ScrollbarTheme::theme().shouldCenterOnThumb(scrollbar, event);
  }
  bool shouldSnapBackToDragOrigin(const ScrollbarThemeClient& scrollbar,
                                  const WebMouseEvent& event) override {
    return ScrollbarTheme::theme().shouldSnapBackToDragOrigin(scrollbar, event);
  }

  double initialAutoscrollTimerDelay() override {
    return ScrollbarTheme::theme().initialAutoscrollTimerDelay();
  }
  double autoscrollTimerDelay() override {
    return ScrollbarTheme::theme().autoscrollTimerDelay();
  }

  void registerScrollbar(ScrollbarThemeClient& scrollbar) override {
    return ScrollbarTheme::theme().registerScrollbar(scrollbar);
  }
  void unregisterScrollbar(ScrollbarThemeClient& scrollbar) override {
    return ScrollbarTheme::theme().unregisterScrollbar(scrollbar);
  }

  int minimumThumbLength(const ScrollbarThemeClient&) override;

  void buttonSizesAlongTrackAxis(const ScrollbarThemeClient&,
                                 int& beforeSize,
                                 int& afterSize);

  static LayoutScrollbarTheme* layoutScrollbarTheme();

 protected:
  bool hasButtons(const ScrollbarThemeClient&) override;
  bool hasThumb(const ScrollbarThemeClient&) override;

  IntRect backButtonRect(const ScrollbarThemeClient&,
                         ScrollbarPart,
                         bool painting = false) override;
  IntRect forwardButtonRect(const ScrollbarThemeClient&,
                            ScrollbarPart,
                            bool painting = false) override;
  IntRect trackRect(const ScrollbarThemeClient&,
                    bool painting = false) override;

  void paintScrollbarBackground(GraphicsContext&, const Scrollbar&) override;
  void paintTrackBackground(GraphicsContext&,
                            const Scrollbar&,
                            const IntRect&) override;
  void paintTrackPiece(GraphicsContext&,
                       const Scrollbar&,
                       const IntRect&,
                       ScrollbarPart) override;
  void paintButton(GraphicsContext&,
                   const Scrollbar&,
                   const IntRect&,
                   ScrollbarPart) override;
  void paintThumb(GraphicsContext&, const Scrollbar&, const IntRect&) override;
  void paintTickmarks(GraphicsContext&,
                      const Scrollbar&,
                      const IntRect&) override;

  IntRect constrainTrackRectToTrackPieces(const ScrollbarThemeClient&,
                                          const IntRect&) override;
};

}  // namespace blink

#endif  // LayoutScrollbarTheme_h