Move *Animation to app/

http://crbug.com/11387

Review URL: http://codereview.chromium.org/109001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@15275 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 122 insertions, 0 deletions

diff --git a/app/animation.h b/app/animation.h
new file mode 100644
index 0000000..58a2c67
--- /dev/null
+++ b/app/animation.h
@@ -0,0 +1,122 @@
+// Copyright (c) 2006-2008 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_ANIMATION_H_
+#define APP_ANIMATION_H_
+
+#include "base/timer.h"
+
+class Animation;
+
+// AnimationDelegate
+//
+//  Implement this interface when you want to receive notifications about the
+//  state of an animation.
+//
+class AnimationDelegate {
+ public:
+  // Called when an animation has started.
+  virtual void AnimationStarted(const Animation* animation) {
+  }
+
+  // Called when an animation has completed.
+  virtual void AnimationEnded(const Animation* animation) {
+  }
+
+  // Called when an animation has progressed.
+  virtual void AnimationProgressed(const Animation* animation) {
+  }
+
+  // Called when an animation has been canceled.
+  virtual void AnimationCanceled(const Animation* animation) {
+  }
+};
+
+// Animation
+//
+//  This class provides a basic implementation of an object that uses a timer
+//  to increment its state over the specified time and frame-rate. To
+//  actually do something useful with this you need to subclass it and override
+//  AnimateToState and optionally GetCurrentValue to update your state.
+//
+//  The Animation notifies a delegate when events of interest occur.
+//
+//  The practice is to instantiate a subclass and call Init and any other
+//  initialization specific to the subclass, and then call |Start|. The
+//  animation uses the current thread's message loop.
+//
+class 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.
+  Animation(int frame_rate, AnimationDelegate* delegate);
+
+  // Initializes all fields.
+  Animation(int duration, int frame_rate, AnimationDelegate* delegate);
+  virtual ~Animation();
+
+  // Reset state so that the animation can be started again.
+  virtual void Reset();
+
+  // Called when the animation progresses. Subclasses override this to
+  // efficiently update their state.
+  virtual void AnimateToState(double state) = 0;
+
+  // 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;
+
+  // Start the animation.
+  void Start();
+
+  // Stop the animation.
+  void Stop();
+
+  // Skip to the end of the current animation.
+  void End();
+
+  // Return whether this animation is animating.
+  bool IsAnimating();
+
+  // Changes the length of the animation. This resets the current
+  // state of the animation to the beginning.
+  void SetDuration(int duration);
+
+ protected:
+  // Overriddable, called by Run.
+  virtual void Step();
+
+  // Calculates the timer interval from the constructor list.
+  int CalculateInterval(int frame_rate);
+
+  // Whether or not we are currently animating.
+  bool animating_;
+
+  int frame_rate_;
+  int timer_interval_;
+  int duration_;
+
+  // For determining state.
+  int iteration_count_;
+  int current_iteration_;
+  double state_;
+
+  AnimationDelegate* delegate_;
+
+  base::RepeatingTimer<Animation> timer_;
+
+ private:
+  // Called when the animation's timer expires, calls Step.
+  void Run();
+
+  DISALLOW_COPY_AND_ASSIGN(Animation);
+};
+
+#endif  // APP_ANIMATION_H_