cc/animation/scrollbar_animation_controller_linear_fade.h

   1 // Copyright 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CC_ANIMATION_SCROLLBAR_ANIMATION_CONTROLLER_LINEAR_FADE_H_
   6 #define CC_ANIMATION_SCROLLBAR_ANIMATION_CONTROLLER_LINEAR_FADE_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "cc/animation/scrollbar_animation_controller.h"
  10 #include "cc/base/cc_export.h"
  11
  12 namespace cc {
  13 class LayerImpl;
  14
  15 class CC_EXPORT ScrollbarAnimationControllerLinearFade
  16     : public ScrollbarAnimationController {
  17  public:
  18   static scoped_ptr<ScrollbarAnimationControllerLinearFade> Create(
  19       LayerImpl* scroll_layer,
  20       base::TimeDelta fadeout_delay,
  21       base::TimeDelta fadeout_length);
  22
  23   virtual ~ScrollbarAnimationControllerLinearFade();
  24
  25   // ScrollbarAnimationController overrides.
  26   virtual bool IsScrollGestureInProgress() const OVERRIDE;
  27   virtual bool IsAnimating() const OVERRIDE;
  28   virtual base::TimeDelta DelayBeforeStart(base::TimeTicks now) const OVERRIDE;
  29
  30   virtual bool Animate(base::TimeTicks now) OVERRIDE;
  31   virtual void DidScrollGestureBegin() OVERRIDE;
  32   virtual void DidScrollGestureEnd(base::TimeTicks now) OVERRIDE;
  33   virtual void DidProgrammaticallyUpdateScroll(base::TimeTicks now) OVERRIDE;
  34
  35  protected:
  36   ScrollbarAnimationControllerLinearFade(LayerImpl* scroll_layer,
  37                                          base::TimeDelta fadeout_delay,
  38                                          base::TimeDelta fadeout_length);
  39
  40  private:
  41   float OpacityAtTime(base::TimeTicks now);
  42
  43   LayerImpl* scroll_layer_;
  44
  45   base::TimeTicks last_awaken_time_;
  46   bool scroll_gesture_in_progress_;
  47
  48   base::TimeDelta fadeout_delay_;
  49   base::TimeDelta fadeout_length_;
  50
  51   DISALLOW_COPY_AND_ASSIGN(ScrollbarAnimationControllerLinearFade);
  52 };
  53
  54 }  // namespace cc
  55
  56 #endif  // CC_ANIMATION_SCROLLBAR_ANIMATION_CONTROLLER_LINEAR_FADE_H_