It is time.

ui/views/controls/slider.h

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef UI_VIEWS_CONTROLS_SLIDER_H_
-#define UI_VIEWS_CONTROLS_SLIDER_H_
-
-#include "ui/gfx/animation/animation_delegate.h"
-#include "ui/views/view.h"
-#include "ui/views/views_export.h"
-
-typedef unsigned int SkColor;
-
-namespace gfx {
-class ImageSkia;
-class SlideAnimation;
-}
-
-namespace views {
-
-namespace test {
-class SliderTestApi;
-}
-
-class Slider;
-
-enum SliderChangeReason {
-  VALUE_CHANGED_BY_USER,  // value was changed by the user (by clicking, e.g.)
-  VALUE_CHANGED_BY_API,   // value was changed by a call to SetValue.
-};
-
-class VIEWS_EXPORT SliderListener {
- public:
-  virtual void SliderValueChanged(Slider* sender,
-                                  float value,
-                                  float old_value,
-                                  SliderChangeReason reason) = 0;
-
-  // Invoked when a drag starts or ends (more specifically, when the mouse
-  // button is pressed or released).
-  virtual void SliderDragStarted(Slider* sender) {}
-  virtual void SliderDragEnded(Slider* sender) {}
-
- protected:
-  virtual ~SliderListener() {}
-};
-
-class VIEWS_EXPORT Slider : public View, public gfx::AnimationDelegate {
- public:
-  enum Orientation {
-    HORIZONTAL,
-    VERTICAL
-  };
-
-  Slider(SliderListener* listener, Orientation orientation);
-  virtual ~Slider();
-
-  float value() const { return value_; }
-  void SetValue(float value);
-
-  // Set the delta used for changing the value via keyboard.
-  void SetKeyboardIncrement(float increment);
-
-  void SetAccessibleName(const base::string16& name);
-
-  void set_enable_accessibility_events(bool enabled) {
-    accessibility_events_enabled_ = enabled;
-  }
-
-  void set_focus_border_color(SkColor color) { focus_border_color_ = color; }
-
-  // Update UI based on control on/off state.
-  void UpdateState(bool control_on);
-
- private:
-  friend class test::SliderTestApi;
-
-  void SetValueInternal(float value, SliderChangeReason reason);
-
-  // Should be called on the Mouse Down event. Used to calculate relative
-  // position of the mouse cursor (or the touch point) on the button to
-  // accurately move the button using the MoveButtonTo() method.
-  void PrepareForMove(const gfx::Point& point);
-
-  // Moves the button to the specified point and updates the value accordingly.
-  void MoveButtonTo(const gfx::Point& point);
-
-  void OnPaintFocus(gfx::Canvas* canvas);
-
-  // Notify the listener_, if not NULL, that dragging started.
-  void OnSliderDragStarted();
-
-  // Notify the listener_, if not NULL, that dragging ended.
-  void OnSliderDragEnded();
-
-  // views::View overrides:
-  virtual gfx::Size GetPreferredSize() const override;
-  virtual void OnPaint(gfx::Canvas* canvas) override;
-  virtual bool OnMousePressed(const ui::MouseEvent& event) override;
-  virtual bool OnMouseDragged(const ui::MouseEvent& event) override;
-  virtual void OnMouseReleased(const ui::MouseEvent& event) override;
-  virtual bool OnKeyPressed(const ui::KeyEvent& event) override;
-  virtual void GetAccessibleState(ui::AXViewState* state) override;
-  virtual void OnFocus() override;
-  virtual void OnBlur() override;
-
-  // ui::EventHandler overrides:
-  virtual void OnGestureEvent(ui::GestureEvent* event) override;
-
-  // gfx::AnimationDelegate overrides:
-  virtual void AnimationProgressed(const gfx::Animation* animation) override;
-
-  void set_listener(SliderListener* listener) {
-    listener_ = listener;
-  }
-
-  SliderListener* listener_;
-  Orientation orientation_;
-
-  scoped_ptr<gfx::SlideAnimation> move_animation_;
-
-  float value_;
-  float keyboard_increment_;
-  float animating_value_;
-  bool value_is_valid_;
-  base::string16 accessible_name_;
-  bool accessibility_events_enabled_;
-  SkColor focus_border_color_;
-
-  // Relative position of the mouse cursor (or the touch point) on the slider's
-  // button.
-  gfx::Point initial_button_offset_;
-
-  const int* bar_active_images_;
-  const int* bar_disabled_images_;
-  const gfx::ImageSkia* thumb_;
-  const gfx::ImageSkia* images_[4];
-  int bar_height_;
-
-  DISALLOW_COPY_AND_ASSIGN(Slider);
-};
-
-}  // namespace views
-
-#endif  // UI_VIEWS_CONTROLS_SLIDER_H_