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. 4 5 #ifndef ASH_SHELF_BACKGROUND_ANIMATOR_H_ 6 #define ASH_SHELF_BACKGROUND_ANIMATOR_H_ 7 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" 12 13 namespace ash { 14 15 // How the background can be changed. 16 enum BackgroundAnimatorChangeType { 17 BACKGROUND_CHANGE_ANIMATE, 18 BACKGROUND_CHANGE_IMMEDIATE 19 }; 20 21 namespace internal { 22 23 // Delegate is notified any time the background changes. 24 class ASH_EXPORT BackgroundAnimatorDelegate { 25 public: 26 virtual void UpdateBackground(int alpha) = 0; 27 28 protected: ~BackgroundAnimatorDelegate()29 virtual ~BackgroundAnimatorDelegate() {} 30 }; 31 32 // BackgroundAnimator is used by the shelf to animate the background (alpha). 33 class ASH_EXPORT BackgroundAnimator : public gfx::AnimationDelegate { 34 public: 35 BackgroundAnimator(BackgroundAnimatorDelegate* delegate, 36 int min_alpha, 37 int max_alpha); 38 virtual ~BackgroundAnimator(); 39 40 // Sets the transition time in ms. 41 void SetDuration(int time_in_ms); 42 43 // Sets whether a background is rendered. Initial value is false. If |type| 44 // is |CHANGE_IMMEDIATE| and an animation is not in progress this notifies 45 // the delegate immediately (synchronously from this method). 46 void SetPaintsBackground(bool value, BackgroundAnimatorChangeType type); paints_background()47 bool paints_background() const { return paints_background_; } 48 49 // Current alpha. alpha()50 int alpha() const { return alpha_; } 51 52 // gfx::AnimationDelegate overrides: 53 virtual void AnimationProgressed(const gfx::Animation* animation) OVERRIDE; 54 55 private: 56 BackgroundAnimatorDelegate* delegate_; 57 58 const int min_alpha_; 59 const int max_alpha_; 60 61 gfx::SlideAnimation animation_; 62 63 // Whether the background is painted. 64 bool paints_background_; 65 66 // Current alpha value of the background. 67 int alpha_; 68 69 DISALLOW_COPY_AND_ASSIGN(BackgroundAnimator); 70 }; 71 72 } // namespace internal 73 } // namespace ash 74 75 #endif // ASH_SHELF_BACKGROUND_ANIMATOR_H_ 76