| // Copyright (c) 2010 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. |
| // Inspired by NSAnimation |
| |
| #ifndef APP_LINEAR_ANIMATION_H_ |
| #define APP_LINEAR_ANIMATION_H_ |
| #pragma once |
| |
| #include "app/animation.h" |
| #include "base/time.h" |
| |
| class AnimationDelegate; |
| |
| // Linear time bounded animation. As the animation progresses AnimateToState is |
| // invoked. |
| class LinearAnimation : public Animation { |
| public: |
| // Initializes everything except the duration. |
| // |
| // Caller must make sure to call SetDuration() if they use this |
| // constructor; it is preferable to use the full one, but sometimes |
| // duration can change between calls to Start() and we need to |
| // expose this interface. |
| LinearAnimation(int frame_rate, AnimationDelegate* delegate); |
| |
| // Initializes all fields. |
| LinearAnimation(int duration, int frame_rate, AnimationDelegate* delegate); |
| |
| // Gets the value for the current state, according to the animation curve in |
| // use. This class provides only for a linear relationship, however subclasses |
| // can override this to provide others. |
| virtual double GetCurrentValue() const; |
| |
| // Skip to the end of the current animation. |
| void End(); |
| |
| // Changes the length of the animation. This resets the current |
| // state of the animation to the beginning. |
| void SetDuration(int duration); |
| |
| protected: |
| // Called when the animation progresses. Subclasses override this to |
| // efficiently update their state. |
| virtual void AnimateToState(double state) = 0; |
| |
| // Invoked by the AnimationContainer when the animation is running to advance |
| // the animation. Use |time_now| rather than Time::Now to avoid multiple |
| // animations running at the same time diverging. |
| virtual void Step(base::TimeTicks time_now); |
| |
| // Overriden to advance to the end (if End was invoked). |
| virtual void AnimationStopped(); |
| |
| // Overriden to return true if state is not 1. |
| virtual bool ShouldSendCanceledFromStop(); |
| |
| private: |
| base::TimeDelta duration_; |
| |
| // Current state, on a scale from 0.0 to 1.0. |
| double state_; |
| |
| // If true, we're in end. This is used to determine if the animation should |
| // be advanced to the end from AnimationStopped. |
| bool in_end_; |
| |
| DISALLOW_COPY_AND_ASSIGN(LinearAnimation); |
| }; |
| |
| #endif // APP_LINEAR_ANIMATION_H_ |