/* * 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 android.animation; import android.util.Log; import android.util.Property; import java.lang.reflect.Method; import java.util.ArrayList; /** * This subclass of {@link ValueAnimator} provides support for animating properties on target objects. * The constructors of this class take parameters to define the target object that will be animated * as well as the name of the property that will be animated. Appropriate set/get functions * are then determined internally and the animation will call these functions as necessary to * animate the property. * *
For more information about animating with {@code ObjectAnimator}, read the * Property * Animation developer guide.
*foo
will result
* in a call to the function setFoo()
on the target object. If either
* valueFrom
or valueTo
is null, then a getter function will
* also be derived and called.
*
* For best performance of the mechanism that calls the setter function determined by the
* name of the property being animated, use float
or int
typed values,
* and make the setter function for those properties have a void
return value. This
* will cause the code to take an optimized path for these constrained circumstances. Other
* property types and return types will work, but will have more overhead in processing
* the requests due to normal reflection mechanisms.
Note that the setter function derived from this property name
* must take the same parameter type as the
* valueFrom
and valueTo
properties, otherwise the call to
* the setter function will fail.
If this ObjectAnimator has been set up to animate several properties together, * using more than one PropertyValuesHolder objects, then setting the propertyName simply * sets the propertyName in the first of those PropertyValuesHolder objects.
* * @param propertyName The name of the property being animated. Should not be null. */ public void setPropertyName(String propertyName) { // mValues could be null if this is being constructed piecemeal. Just record the // propertyName to be used later when setValues() is called if so. if (mValues != null) { PropertyValuesHolder valuesHolder = mValues[0]; String oldName = valuesHolder.getPropertyName(); valuesHolder.setPropertyName(propertyName); mValuesMap.remove(oldName); mValuesMap.put(propertyName, valuesHolder); } mPropertyName = propertyName; // New property/values/target should cause re-initialization prior to starting mInitialized = false; } /** * Sets the property that will be animated. Property objects will take precedence over * properties specified by the {@link #setPropertyName(String)} method. Animations should * be set up to use one or the other, not both. * * @param property The property being animated. Should not be null. */ public void setProperty(Property property) { // mValues could be null if this is being constructed piecemeal. Just record the // propertyName to be used later when setValues() is called if so. if (mValues != null) { PropertyValuesHolder valuesHolder = mValues[0]; String oldName = valuesHolder.getPropertyName(); valuesHolder.setProperty(property); mValuesMap.remove(oldName); mValuesMap.put(mPropertyName, valuesHolder); } if (mProperty != null) { mPropertyName = property.getName(); } mProperty = property; // New property/values/target should cause re-initialization prior to starting mInitialized = false; } /** * Gets the name of the property that will be animated. This name will be used to derive * a setter function that will be called to set animated values. * For example, a property name offoo
will result
* in a call to the function setFoo()
on the target object. If either
* valueFrom
or valueTo
is null, then a getter function will
* also be derived and called.
*/
public String getPropertyName() {
return mPropertyName;
}
/**
* Creates a new ObjectAnimator object. This default constructor is primarily for
* use internally; the other constructors which take parameters are more generally
* useful.
*/
public ObjectAnimator() {
}
/**
* Private utility constructor that initializes the target object and name of the
* property being animated.
*
* @param target The object whose property is to be animated. This object should
* have a public method on it called setName()
, where name
is
* the value of the propertyName
parameter.
* @param propertyName The name of the property being animated.
*/
private ObjectAnimator(Object target, String propertyName) {
mTarget = target;
setPropertyName(propertyName);
}
/**
* Private utility constructor that initializes the target object and property being animated.
*
* @param target The object whose property is to be animated.
* @param property The property being animated.
*/
private setName()
, where name
is
* the value of the propertyName
parameter.
* @param propertyName The name of the property being animated.
* @param values A set of values that the animation will animate between over time.
* @return An ObjectAnimator object that is set up to animate between the given values.
*/
public static ObjectAnimator ofInt(Object target, String propertyName, int... values) {
ObjectAnimator anim = new ObjectAnimator(target, propertyName);
anim.setIntValues(values);
return anim;
}
/**
* Constructs and returns an ObjectAnimator that animates between int values. A single
* value implies that that value is the one being animated to. Two values imply a starting
* and ending values. More than two values imply a starting value, values to animate through
* along the way, and an ending value (these values will be distributed evenly across
* the duration of the animation).
*
* @param target The object whose property is to be animated.
* @param property The property being animated.
* @param values A set of values that the animation will animate between over time.
* @return An ObjectAnimator object that is set up to animate between the given values.
*/
public static setName()
, where name
is
* the value of the propertyName
parameter.
* @param propertyName The name of the property being animated.
* @param values A set of values that the animation will animate between over time.
* @return An ObjectAnimator object that is set up to animate between the given values.
*/
public static ObjectAnimator ofFloat(Object target, String propertyName, float... values) {
ObjectAnimator anim = new ObjectAnimator(target, propertyName);
anim.setFloatValues(values);
return anim;
}
/**
* Constructs and returns an ObjectAnimator that animates between float values. A single
* value implies that that value is the one being animated to. Two values imply a starting
* and ending values. More than two values imply a starting value, values to animate through
* along the way, and an ending value (these values will be distributed evenly across
* the duration of the animation).
*
* @param target The object whose property is to be animated.
* @param property The property being animated.
* @param values A set of values that the animation will animate between over time.
* @return An ObjectAnimator object that is set up to animate between the given values.
*/
public static setName()
, where name
is
* the value of the propertyName
parameter.
* @param propertyName The name of the property being animated.
* @param evaluator A TypeEvaluator that will be called on each animation frame to
* provide the necessary interpolation between the Object values to derive the animated
* value.
* @param values A set of values that the animation will animate between over time.
* @return An ObjectAnimator object that is set up to animate between the given values.
*/
public static ObjectAnimator ofObject(Object target, String propertyName,
TypeEvaluator evaluator, Object... values) {
ObjectAnimator anim = new ObjectAnimator(target, propertyName);
anim.setObjectValues(values);
anim.setEvaluator(evaluator);
return anim;
}
/**
* Constructs and returns an ObjectAnimator that animates between Object values. A single
* value implies that that value is the one being animated to. Two values imply a starting
* and ending values. More than two values imply a starting value, values to animate through
* along the way, and an ending value (these values will be distributed evenly across
* the duration of the animation).
*
* @param target The object whose property is to be animated.
* @param property The property being animated.
* @param evaluator A TypeEvaluator that will be called on each animation frame to
* provide the necessary interpolation between the Object values to derive the animated
* value.
* @param values A set of values that the animation will animate between over time.
* @return An ObjectAnimator object that is set up to animate between the given values.
*/
public static PropertyValueHolder
objects. This variant should be used when animating
* several properties at once with the same ObjectAnimator, since PropertyValuesHolder allows
* you to associate a set of animation values with a property name.
*
* @param target The object whose property is to be animated. Depending on how the
* PropertyValuesObjects were constructed, the target object should either have the {@link
* android.util.Property} objects used to construct the PropertyValuesHolder objects or (if the
* PropertyValuesHOlder objects were created with property names) the target object should have
* public methods on it called setName()
, where name
is the name of
* the property passed in as the propertyName
parameter for each of the
* PropertyValuesHolder objects.
* @param values A set of PropertyValuesHolder objects whose values will be animated between
* over time.
* @return An ObjectAnimator object that is set up to animate between the given values.
*/
public static ObjectAnimator ofPropertyValuesHolder(Object target,
PropertyValuesHolder... values) {
ObjectAnimator anim = new ObjectAnimator();
anim.mTarget = target;
anim.setValues(values);
return anim;
}
@Override
public void setIntValues(int... values) {
if (mValues == null || mValues.length == 0) {
// No values yet - this animator is being constructed piecemeal. Init the values with
// whatever the current propertyName is
if (mProperty != null) {
setValues(PropertyValuesHolder.ofInt(mProperty, values));
} else {
setValues(PropertyValuesHolder.ofInt(mPropertyName, values));
}
} else {
super.setIntValues(values);
}
}
@Override
public void setFloatValues(float... values) {
if (mValues == null || mValues.length == 0) {
// No values yet - this animator is being constructed piecemeal. Init the values with
// whatever the current propertyName is
if (mProperty != null) {
setValues(PropertyValuesHolder.ofFloat(mProperty, values));
} else {
setValues(PropertyValuesHolder.ofFloat(mPropertyName, values));
}
} else {
super.setFloatValues(values);
}
}
@Override
public void setObjectValues(Object... values) {
if (mValues == null || mValues.length == 0) {
// No values yet - this animator is being constructed piecemeal. Init the values with
// whatever the current propertyName is
if (mProperty != null) {
setValues(PropertyValuesHolder.ofObject(mProperty, (TypeEvaluator)null, values));
} else {
setValues(PropertyValuesHolder.ofObject(mPropertyName, (TypeEvaluator)null, values));
}
} else {
super.setObjectValues(values);
}
}
@Override
public void start() {
if (DBG) {
Log.d("ObjectAnimator", "Anim target, duration: " + mTarget + ", " + getDuration());
for (int i = 0; i < mValues.length; ++i) {
PropertyValuesHolder pvh = mValues[i];
ArrayListstartDelay
, the
* function is called after that delay ends.
* It takes care of the final initialization steps for the
* animation. This includes setting mEvaluator, if the user has not yet
* set it up, and the setter/getter methods, if the user did not supply
* them.
*
* Overriders of this method should call the superclass method to cause * internal mechanisms to be set up correctly.
*/ @Override void initAnimation() { if (!mInitialized) { // mValueType may change due to setter/getter setup; do this before calling super.init(), // which uses mValueType to set up the default type evaluator. int numValues = mValues.length; for (int i = 0; i < numValues; ++i) { mValues[i].setupSetterAndGetter(mTarget); } super.initAnimation(); } } /** * Sets the length of the animation. The default duration is 300 milliseconds. * * @param duration The length of the animation, in milliseconds. * @return ObjectAnimator The object called with setDuration(). This return * value makes it easier to compose statements together that construct and then set the * duration, as in *ObjectAnimator.ofInt(target, propertyName, 0, 10).setDuration(500).start()
.
*/
@Override
public ObjectAnimator setDuration(long duration) {
super.setDuration(duration);
return this;
}
/**
* The target object whose property will be animated by this animation
*
* @return The object being animated
*/
public Object getTarget() {
return mTarget;
}
/**
* Sets the target object whose property will be animated by this animation
*
* @param target The object being animated
*/
@Override
public void setTarget(Object target) {
if (mTarget != target) {
final Object oldTarget = mTarget;
mTarget = target;
if (oldTarget != null && target != null && oldTarget.getClass() == target.getClass()) {
return;
}
// New target type should cause re-initialization prior to starting
mInitialized = false;
}
}
@Override
public void setupStartValues() {
initAnimation();
int numValues = mValues.length;
for (int i = 0; i < numValues; ++i) {
mValues[i].setupStartValue(mTarget);
}
}
@Override
public void setupEndValues() {
initAnimation();
int numValues = mValues.length;
for (int i = 0; i < numValues; ++i) {
mValues[i].setupEndValue(mTarget);
}
}
/**
* This method is called with the elapsed fraction of the animation during every
* animation frame. This function turns the elapsed fraction into an interpolated fraction
* and then into an animated value (from the evaluator. The function is called mostly during
* animation updates, but it is also called when the end()
* function is called, to set the final value on the property.
*
* Overrides of this method must call the superclass to perform the calculation * of the animated value.
* * @param fraction The elapsed fraction of the animation. */ @Override void animateValue(float fraction) { super.animateValue(fraction); int numValues = mValues.length; for (int i = 0; i < numValues; ++i) { mValues[i].setAnimatedValue(mTarget); } } @Override public ObjectAnimator clone() { final ObjectAnimator anim = (ObjectAnimator) super.clone(); return anim; } @Override public String toString() { String returnVal = "ObjectAnimator@" + Integer.toHexString(hashCode()) + ", target " + mTarget; if (mValues != null) { for (int i = 0; i < mValues.length; ++i) { returnVal += "\n " + mValues[i].toString(); } } return returnVal; } }