Updating trunk VERSION from 2139.0 to 2140.0
[chromium-blink-merge.git] / ash / shelf / background_animator.h
blob37be3be56d9d7d13cdc32f67e8997962c2c73cb9
1 // Copyright (c) 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.
5 #ifndef ASH_SHELF_BACKGROUND_ANIMATOR_H_
6 #define ASH_SHELF_BACKGROUND_ANIMATOR_H_
8 #include "ash/ash_export.h"
9 #include "base/basictypes.h"
10 #include "ui/gfx/animation/animation_delegate.h"
11 #include "ui/gfx/animation/slide_animation.h"
13 namespace ash {
15 // How the background can be changed.
16 enum BackgroundAnimatorChangeType {
17 BACKGROUND_CHANGE_ANIMATE,
18 BACKGROUND_CHANGE_IMMEDIATE
21 // Delegate is notified any time the background changes.
22 class ASH_EXPORT BackgroundAnimatorDelegate {
23 public:
24 virtual void UpdateBackground(int alpha) = 0;
26 protected:
27 virtual ~BackgroundAnimatorDelegate() {}
30 // BackgroundAnimator is used by the shelf to animate the background (alpha).
31 class ASH_EXPORT BackgroundAnimator : public gfx::AnimationDelegate {
32 public:
33 BackgroundAnimator(BackgroundAnimatorDelegate* delegate,
34 int min_alpha,
35 int max_alpha);
36 virtual ~BackgroundAnimator();
38 // Sets the transition time in ms.
39 void SetDuration(int time_in_ms);
41 // Sets whether a background is rendered. Initial value is false. If |type|
42 // is |CHANGE_IMMEDIATE| and an animation is not in progress this notifies
43 // the delegate immediately (synchronously from this method).
44 void SetPaintsBackground(bool value, BackgroundAnimatorChangeType type);
45 bool paints_background() const { return paints_background_; }
47 // Current alpha.
48 int alpha() const { return alpha_; }
50 // gfx::AnimationDelegate overrides:
51 virtual void AnimationProgressed(const gfx::Animation* animation) OVERRIDE;
53 private:
54 BackgroundAnimatorDelegate* delegate_;
56 const int min_alpha_;
57 const int max_alpha_;
59 gfx::SlideAnimation animation_;
61 // Whether the background is painted.
62 bool paints_background_;
64 // Current alpha value of the background.
65 int alpha_;
67 DISALLOW_COPY_AND_ASSIGN(BackgroundAnimator);
70 } // namespace ash
72 #endif // ASH_SHELF_BACKGROUND_ANIMATOR_H_