/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.actionbarsherlock.internal.nineoldandroids.animation;
import java.util.ArrayList;
import android.view.animation.Interpolator;
/**
* This is the superclass for classes which provide basic support for animations which can be
* started, ended, and have <code>AnimatorListeners</code> added to them.
*/
public abstract class Animator implements Cloneable {
/**
* The set of listeners to be sent events through the life of an animation.
*/
ArrayList<AnimatorListener> mListeners = null;
/**
* Starts this animation. If the animation has a nonzero startDelay, the animation will start
* running after that delay elapses. A non-delayed animation will have its initial
* value(s) set immediately, followed by calls to
* {@link AnimatorListener#onAnimationStart(Animator)} for any listeners of this animator.
*
* <p>The animation started by calling this method will be run on the thread that called
* this method. This thread should have a Looper on it (a runtime exception will be thrown if
* this is not the case). Also, if the animation will animate
* properties of objects in the view hierarchy, then the calling thread should be the UI
* thread for that view hierarchy.</p>
*
*/
public void start() {
}
/**
* Cancels the animation. Unlike {@link #end()}, <code>cancel()</code> causes the animation to
* stop in its tracks, sending an
* {@link android.animation.Animator.AnimatorListener#onAnimationCancel(Animator)} to
* its listeners, followed by an
* {@link android.animation.Animator.AnimatorListener#onAnimationEnd(Animator)} message.
*
* <p>This method must be called on the thread that is running the animation.</p>
*/
public void cancel() {
}
/**
* Ends the animation. This causes the animation to assign the end value of the property being
* animated, then calling the
* {@link android.animation.Animator.AnimatorListener#onAnimationEnd(Animator)} method on
* its listeners.
*
* <p>This method must be called on the thread that is running the animation.</p>
*/
public void end() {
}
/**
* The amount of time, in milliseconds, to delay starting the animation after
* {@link #start()} is called.
*
* @return the number of milliseconds to delay running the animation
*/
public abstract long getStartDelay();
/**
* The amount of time, in milliseconds, to delay starting the animation after
* {@link #start()} is called.
* @param startDelay The amount of the delay, in milliseconds
*/
public abstract void setStartDelay(long startDelay);
/**
* Sets the length of the animation.
*
* @param duration The length of the animation, in milliseconds.
*/
public abstract Animator setDuration(long duration);
/**
* Gets the length of the animation.
*
* @return The length of the animation, in milliseconds.
*/
public abstract long getDuration();
/**
* The time interpolator used in calculating the elapsed fraction of this animation. The
* interpolator determines whether the animation runs with linear or non-linear motion,
* such as acceleration and deceleration. The default value is
* {@link android.view.animation.AccelerateDecelerateInterpolator}
*
* @param value the interpolator to be used by this animation
*/
public abstract void setInterpolator(/*Time*/Interpolator value);
/**
* Returns whether this Animator is currently running (having been started and gone past any
* initial startDelay period and not yet ended).
*
* @return Whether the Animator is running.
*/
public abstract boolean isRunning();
/**
* Returns whether this Animator has been started and not yet ended. This state is a superset
* of the state of {@link #isRunning()}, because an Animator with a nonzero
* {@link #getStartDelay() startDelay} will return true for {@link #isStarted()} during the
* delay phase, whereas {@link #isRunning()} will return true only after the delay phase
* is complete.
*
* @return Whether the Animator has been started and not yet ended.
*/
public boolean isStarted() {
// Default method returns value for isRunning(). Subclasses should override to return a
// real value.
return isRunning();
}
/**
* Adds a listener to the set of listeners that are sent events through the life of an
* animation, such as start, repeat, and end.
*
* @param listener the listener to be added to the current set of listeners for this animation.
*/
public void addListener(AnimatorListener listener) {
if (mListeners == null) {
mListeners = new ArrayList<AnimatorListener>();
}
mListeners.add(listener);
}
/**
* Removes a listener from the set listening to this animation.
*
* @param listener the listener to be removed from the current set of listeners for this
* animation.
*/
public void removeListener(AnimatorListener listener) {
if (mListeners == null) {
return;
}
mListeners.remove(listener);
if (mListeners.size() == 0) {
mListeners = null;
}
}
/**
* Gets the set of {@link android.animation.Animator.AnimatorListener} objects that are currently
* listening for events on this <code>Animator</code> object.
*
* @return ArrayList<AnimatorListener> The set of listeners.
*/
public ArrayList<AnimatorListener> getListeners() {
return mListeners;
}
/**
* Removes all listeners from this object. This is equivalent to calling
* <code>getListeners()</code> followed by calling <code>clear()</code> on the
* returned list of listeners.
*/
public void removeAllListeners() {
if (mListeners != null) {
mListeners.clear();
mListeners = null;
}
}
@Override
public Animator clone() {
try {
final Animator anim = (Animator) super.clone();
if (mListeners != null) {
ArrayList<AnimatorListener> oldListeners = mListeners;
anim.mListeners = new ArrayList<AnimatorListener>();
int numListeners = oldListeners.size();
for (int i = 0; i < numListeners; ++i) {
anim.mListeners.add(oldListeners.get(i));
}
}
return anim;
} catch (CloneNotSupportedException e) {
throw new AssertionError();
}
}
/**
* This method tells the object to use appropriate information to extract
* starting values for the animation. For example, a AnimatorSet object will pass
* this call to its child objects to tell them to set up the values. A
* ObjectAnimator object will use the information it has about its target object
* and PropertyValuesHolder objects to get the start values for its properties.
* An ValueAnimator object will ignore the request since it does not have enough
* information (such as a target object) to gather these values.
*/
public void setupStartValues() {
}
/**
* This method tells the object to use appropriate information to extract
* ending values for the animation. For example, a AnimatorSet object will pass
* this call to its child objects to tell them to set up the values. A
* ObjectAnimator object will use the information it has about its target object
* and PropertyValuesHolder objects to get the start values for its properties.
* An ValueAnimator object will ignore the request since it does not have enough
* information (such as a target object) to gather these values.
*/
public void setupEndValues() {
}
/**
* Sets the target object whose property will be animated by this animation. Not all subclasses
* operate on target objects (for example, {@link ValueAnimator}, but this method
* is on the superclass for the convenience of dealing generically with those subclasses
* that do handle targets.
*
* @param target The object being animated
*/
public void setTarget(Object target) {
}
/**
* <p>An animation listener receives notifications from an animation.
* Notifications indicate animation related events, such as the end or the
* repetition of the animation.</p>
*/
public static interface AnimatorListener {
/**
* <p>Notifies the start of the animation.</p>
*
* @param animation The started animation.
*/
void onAnimationStart(Animator animation);
/**
* <p>Notifies the end of the animation. This callback is not invoked
* for animations with repeat count set to INFINITE.</p>
*
* @param animation The animation which reached its end.
*/
void onAnimationEnd(Animator animation);
/**
* <p>Notifies the cancellation of the animation. This callback is not invoked
* for animations with repeat count set to INFINITE.</p>
*
* @param animation The animation which was canceled.
*/
void onAnimationCancel(Animator animation);
/**
* <p>Notifies the repetition of the animation.</p>
*
* @param animation The animation which was repeated.
*/
void onAnimationRepeat(Animator animation);
}
}