content: /*
   * 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.annotation.CallSuper;
  import android.annotation.NonNull;
  import android.annotation.Nullable;
  import android.graphics.Path;
  import android.graphics.PointF;
  import android.util.Log;
  import android.util.Property;
  import android.view.animation.AccelerateDecelerateInterpolator;
  
  import java.lang.ref.WeakReference;
  
  /**
   * 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.
   *
   * <p>Animators can be created from either code or resource files, as shown here:</p>
   *
   * {@sample development/samples/ApiDemos/res/anim/object_animator.xml ObjectAnimatorResources}
   *
   * <p>Starting from API 23, it is possible to use {@link PropertyValuesHolder} and
   * {@link Keyframe} in resource files to create more complex animations. Using PropertyValuesHolders
   * allows animators to animate several properties in parallel, as shown in this sample:</p>
   *
   * {@sample development/samples/ApiDemos/res/anim/object_animator_pvh.xml
   * PropertyValuesHolderResources}
   *
   * <p>Using Keyframes allows animations to follow more complex paths from the start
   * to the end values. Note that you can specify explicit fractional values (from 0 to 1) for
   * each keyframe to determine when, in the overall duration, the animation should arrive at that
   * value. Alternatively, you can leave the fractions off and the keyframes will be equally
   * distributed within the total duration. Also, a keyframe with no value will derive its value
   * from the target object when the animator starts, just like animators with only one
   * value specified. In addition, an optional interpolator can be specified. The interpolator will
   * be applied on the interval between the keyframe that the interpolator is set on and the previous
   * keyframe. When no interpolator is supplied, the default {@link AccelerateDecelerateInterpolator}
   * will be used. </p>
   *
   * {@sample development/samples/ApiDemos/res/anim/object_animator_pvh_kf_interpolated.xml KeyframeResources}
   *
   * <div class="special reference">
   * <h3>Developer Guides</h3>
   * <p>For more information about animating with {@code ObjectAnimator}, read the
   * <a href="{@docRoot}guide/topics/graphics/prop-animation.html#object-animator">Property
   * Animation</a> developer guide.</p>
   * </div>
   *
   * @see #setPropertyName(String)
   *
   */
  public final class ObjectAnimator extends ValueAnimator {
      private static final String LOG_TAG = "ObjectAnimator";
  
      private static final boolean DBG = false;
  
      /**
       * A weak reference to the target object on which the property exists, set
       * in the constructor. We'll cancel the animation if this goes away.
       */
      private WeakReference<Object> mTarget;
  
      private String mPropertyName;
  
      private Property mProperty;
  
      private boolean mAutoCancel = false;
  
      /**
       * Sets the name of the property that will be animated. This name is used to derive
       * a setter function that will be called to set animated values.
       * For example, a property name of <code>foo</code> will result
       * in a call to the function <code>setFoo()</code> on the target object. If either
       * <code>valueFrom</code> or <code>valueTo</code> is null, then a getter function will
       * also be derived and called.
       *
       * <p>For best performance of the mechanism that calls the setter function determined by the
       * name of the property being animated, use <code>float</code> or <code>int</code> typed values,
       * and make the setter function for those properties have a <code>void</code> 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.</p>
       *
       * <p>Note that the setter function derived from this property name
       * must take the same parameter type as the
       * <code>valueFrom</code> and <code>valueTo</code> properties, otherwise the call to
       * the setter function will fail.</p>
       *
       * <p>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.</p>
       *
       * @param propertyName The name of the property being animated. Should not be null.
       */
      public void setPropertyName(@NonNull 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(@NonNull 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 of <code>foo</code> will result
       * in a call to the function <code>setFoo()</code> on the target object. If either
       * <code>valueFrom</code> or <code>valueTo</code> is null, then a getter function will
       * also be derived and called.
       *
       * <p>If this animator was created with a {@link Property} object instead of the
       * string name of a property, then this method will return the {@link
       * Property#getName() name} of that Property object instead. If this animator was
       * created with one or more {@link PropertyValuesHolder} objects, then this method
       * will return the {@link PropertyValuesHolder#getPropertyName() name} of that
       * object (if there was just one) or a comma-separated list of all of the
       * names (if there are more than one).</p>
       */
      @Nullable
      public String getPropertyName() {
          String propertyName = null;
          if (mPropertyName != null) {
              propertyName = mPropertyName;
          } else if (mProperty != null) {
              propertyName = mProperty.getName();
          } else if (mValues != null && mValues.length > 0) {
              for (int i = 0; i < mValues.length; ++i) {
                  if (i == 0) {
                      propertyName = "";
                  } else {
                      propertyName += ",";
                  }
                  propertyName += mValues[i].getPropertyName();
              }
          }
          return propertyName;
      }
  
      @Override
      String getNameForTrace() {
          return "animator:" + getPropertyName();
      }
  
      /**
       * 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 <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> parameter.
       * @param propertyName The name of the property being animated.
       */
      private ObjectAnimator(Object target, String propertyName) {
          setTarget(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 <T> ObjectAnimator(T target, Property<T, ?> property) {
          setTarget(target);
          setProperty(property);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between int values. A single
       * value implies that that value is the one being animated to, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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. This object should
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> 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 coordinates along a <code>Path</code>
       * using two properties. A <code>Path</code></> animation moves in two dimensions, animating
       * coordinates <code>(x, y)</code> together to follow the line. In this variation, the
       * coordinates are integers that are set to separate properties designated by
       * <code>xPropertyName</code> and <code>yPropertyName</code>.
       *
       * @param target The object whose properties are to be animated. This object should
       *               have public methods on it called <code>setNameX()</code> and
       *               <code>setNameY</code>, where <code>nameX</code> and <code>nameY</code>
       *               are the value of <code>xPropertyName</code> and <code>yPropertyName</code>
       *               parameters, respectively.
       * @param xPropertyName The name of the property for the x coordinate being animated.
       * @param yPropertyName The name of the property for the y coordinate being animated.
       * @param path The <code>Path</code> to animate values along.
       * @return An ObjectAnimator object that is set up to animate along <code>path</code>.
       */
      public static ObjectAnimator ofInt(Object target, String xPropertyName, String yPropertyName,
              Path path) {
          PathKeyframes keyframes = KeyframeSet.ofPath(path);
          PropertyValuesHolder x = PropertyValuesHolder.ofKeyframes(xPropertyName,
                  keyframes.createXIntKeyframes());
          PropertyValuesHolder y = PropertyValuesHolder.ofKeyframes(yPropertyName,
                  keyframes.createYIntKeyframes());
          return ofPropertyValuesHolder(target, x, y);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between int values. A single
       * value implies that that value is the one being animated to, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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 <T> ObjectAnimator ofInt(T target, Property<T, Integer> property, int... values) {
          ObjectAnimator anim = new ObjectAnimator(target, property);
          anim.setIntValues(values);
          return anim;
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates coordinates along a <code>Path</code>
       * using two properties.  A <code>Path</code></> animation moves in two dimensions, animating
       * coordinates <code>(x, y)</code> together to follow the line. In this variation, the
       * coordinates are integers that are set to separate properties, <code>xProperty</code> and
       * <code>yProperty</code>.
       *
       * @param target The object whose properties are to be animated.
       * @param xProperty The property for the x coordinate being animated.
       * @param yProperty The property for the y coordinate being animated.
       * @param path The <code>Path</code> to animate values along.
       * @return An ObjectAnimator object that is set up to animate along <code>path</code>.
       */
      public static <T> ObjectAnimator ofInt(T target, Property<T, Integer> xProperty,
              Property<T, Integer> yProperty, Path path) {
          PathKeyframes keyframes = KeyframeSet.ofPath(path);
          PropertyValuesHolder x = PropertyValuesHolder.ofKeyframes(xProperty,
                  keyframes.createXIntKeyframes());
          PropertyValuesHolder y = PropertyValuesHolder.ofKeyframes(yProperty,
                  keyframes.createYIntKeyframes());
          return ofPropertyValuesHolder(target, x, y);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates over int values for a multiple
       * parameters setter. Only public methods that take only int parameters are supported.
       * Each <code>int[]</code> contains a complete set of parameters to the setter method.
       * At least two <code>int[]</code> values must be provided, a start and end. 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. This object may
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> parameter. <code>propertyName</code> may also
       * be the case-sensitive complete name of the public setter method.
       * @param propertyName The name of the property being animated or the name of the setter method.
       * @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 ofMultiInt(Object target, String propertyName, int[][] values) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofMultiInt(propertyName, values);
          return ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates the target using a multi-int setter
       * along the given <code>Path</code>. A <code>Path</code></> animation moves in two dimensions,
       * animating coordinates <code>(x, y)</code> together to follow the line. In this variation, the
       * coordinates are integer x and y coordinates used in the first and second parameter of the
       * setter, respectively.
       *
       * @param target The object whose property is to be animated. This object may
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> parameter. <code>propertyName</code> may also
       * be the case-sensitive complete name of the public setter method.
       * @param propertyName The name of the property being animated or the name of the setter method.
       * @param path The <code>Path</code> to animate values along.
       * @return An ObjectAnimator object that is set up to animate along <code>path</code>.
       */
      public static ObjectAnimator ofMultiInt(Object target, String propertyName, Path path) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofMultiInt(propertyName, path);
          return ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates over values for a multiple int
       * parameters setter. Only public methods that take only int parameters are supported.
       * <p>At least two values must be provided, a start and end. 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).</p>
       *
       * @param target The object whose property is to be animated. This object may
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> parameter. <code>propertyName</code> may also
       * be the case-sensitive complete name of the public setter method.
       * @param propertyName The name of the property being animated or the name of the setter method.
       * @param converter Converts T objects into int parameters for the multi-value setter.
       * @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.
       */
      @SafeVarargs
      public static <T> ObjectAnimator ofMultiInt(Object target, String propertyName,
              TypeConverter<T, int[]> converter, TypeEvaluator<T> evaluator, T... values) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofMultiInt(propertyName, converter,
                  evaluator, values);
          return ObjectAnimator.ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between color values. A single
       * value implies that that value is the one being animated to, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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. This object should
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> 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 ofArgb(Object target, String propertyName, int... values) {
          ObjectAnimator animator = ofInt(target, propertyName, values);
          animator.setEvaluator(ArgbEvaluator.getInstance());
          return animator;
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between color values. A single
       * value implies that that value is the one being animated to, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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 <T> ObjectAnimator ofArgb(T target, Property<T, Integer> property,
              int... values) {
          ObjectAnimator animator = ofInt(target, property, values);
          animator.setEvaluator(ArgbEvaluator.getInstance());
          return animator;
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between float values. A single
       * value implies that that value is the one being animated to, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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. This object should
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> 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 coordinates along a <code>Path</code>
       * using two properties. A <code>Path</code></> animation moves in two dimensions, animating
       * coordinates <code>(x, y)</code> together to follow the line. In this variation, the
       * coordinates are floats that are set to separate properties designated by
       * <code>xPropertyName</code> and <code>yPropertyName</code>.
       *
       * @param target The object whose properties are to be animated. This object should
       *               have public methods on it called <code>setNameX()</code> and
       *               <code>setNameY</code>, where <code>nameX</code> and <code>nameY</code>
       *               are the value of the <code>xPropertyName</code> and <code>yPropertyName</code>
       *               parameters, respectively.
       * @param xPropertyName The name of the property for the x coordinate being animated.
       * @param yPropertyName The name of the property for the y coordinate being animated.
       * @param path The <code>Path</code> to animate values along.
       * @return An ObjectAnimator object that is set up to animate along <code>path</code>.
       */
      public static ObjectAnimator ofFloat(Object target, String xPropertyName, String yPropertyName,
              Path path) {
          PathKeyframes keyframes = KeyframeSet.ofPath(path);
          PropertyValuesHolder x = PropertyValuesHolder.ofKeyframes(xPropertyName,
                  keyframes.createXFloatKeyframes());
          PropertyValuesHolder y = PropertyValuesHolder.ofKeyframes(yPropertyName,
                  keyframes.createYFloatKeyframes());
          return ofPropertyValuesHolder(target, x, y);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between float values. A single
       * value implies that that value is the one being animated to, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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 <T> ObjectAnimator ofFloat(T target, Property<T, Float> property,
              float... values) {
          ObjectAnimator anim = new ObjectAnimator(target, property);
          anim.setFloatValues(values);
          return anim;
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates coordinates along a <code>Path</code>
       * using two properties. A <code>Path</code></> animation moves in two dimensions, animating
       * coordinates <code>(x, y)</code> together to follow the line. In this variation, the
       * coordinates are floats that are set to separate properties, <code>xProperty</code> and
       * <code>yProperty</code>.
       *
       * @param target The object whose properties are to be animated.
       * @param xProperty The property for the x coordinate being animated.
       * @param yProperty The property for the y coordinate being animated.
       * @param path The <code>Path</code> to animate values along.
       * @return An ObjectAnimator object that is set up to animate along <code>path</code>.
       */
      public static <T> ObjectAnimator ofFloat(T target, Property<T, Float> xProperty,
              Property<T, Float> yProperty, Path path) {
          PathKeyframes keyframes = KeyframeSet.ofPath(path);
          PropertyValuesHolder x = PropertyValuesHolder.ofKeyframes(xProperty,
                  keyframes.createXFloatKeyframes());
          PropertyValuesHolder y = PropertyValuesHolder.ofKeyframes(yProperty,
                  keyframes.createYFloatKeyframes());
          return ofPropertyValuesHolder(target, x, y);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates over float values for a multiple
       * parameters setter. Only public methods that take only float parameters are supported.
       * Each <code>float[]</code> contains a complete set of parameters to the setter method.
       * At least two <code>float[]</code> values must be provided, a start and end. 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. This object may
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> parameter. <code>propertyName</code> may also
       * be the case-sensitive complete name of the public setter method.
       * @param propertyName The name of the property being animated or the name of the setter method.
       * @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 ofMultiFloat(Object target, String propertyName,
              float[][] values) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofMultiFloat(propertyName, values);
          return ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates the target using a multi-float setter
       * along the given <code>Path</code>. A <code>Path</code></> animation moves in two dimensions,
       * animating coordinates <code>(x, y)</code> together to follow the line. In this variation, the
       * coordinates are float x and y coordinates used in the first and second parameter of the
       * setter, respectively.
       *
       * @param target The object whose property is to be animated. This object may
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> parameter. <code>propertyName</code> may also
       * be the case-sensitive complete name of the public setter method.
       * @param propertyName The name of the property being animated or the name of the setter method.
       * @param path The <code>Path</code> to animate values along.
       * @return An ObjectAnimator object that is set up to animate along <code>path</code>.
       */
      public static ObjectAnimator ofMultiFloat(Object target, String propertyName, Path path) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofMultiFloat(propertyName, path);
          return ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates over values for a multiple float
       * parameters setter. Only public methods that take only float parameters are supported.
       * <p>At least two values must be provided, a start and end. 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).</p>
       *
       * @param target The object whose property is to be animated. This object may
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> parameter. <code>propertyName</code> may also
       * be the case-sensitive complete name of the public setter method.
       * @param propertyName The name of the property being animated or the name of the setter method.
       * @param converter Converts T objects into float parameters for the multi-value setter.
       * @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.
       */
      @SafeVarargs
      public static <T> ObjectAnimator ofMultiFloat(Object target, String propertyName,
              TypeConverter<T, float[]> converter, TypeEvaluator<T> evaluator, T... values) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofMultiFloat(propertyName, converter,
                  evaluator, values);
          return ObjectAnimator.ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between Object values. A single
       * value implies that that value is the one being animated to, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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).
       *
       * <p><strong>Note:</strong> The values are stored as references to the original
       * objects, which means that changes to those objects after this method is called will
       * affect the values on the animator. If the objects will be mutated externally after
       * this method is called, callers should pass a copy of those objects instead.
       *
       * @param target The object whose property is to be animated. This object should
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> 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 a property along a <code>Path</code>.
       * A <code>Path</code></> animation moves in two dimensions, animating coordinates
       * <code>(x, y)</code> together to follow the line. This variant animates the coordinates
       * in a <code>PointF</code> to follow the <code>Path</code>. If the <code>Property</code>
       * associated with <code>propertyName</code> uses a type other than <code>PointF</code>,
       * <code>converter</code> can be used to change from <code>PointF</code> to the type
       * associated with the <code>Property</code>.
       *
       * @param target The object whose property is to be animated. This object should
       * have a public method on it called <code>setName()</code>, where <code>name</code> is
       * the value of the <code>propertyName</code> parameter.
       * @param propertyName The name of the property being animated.
       * @param converter Converts a PointF to the type associated with the setter. May be
       *                  null if conversion is unnecessary.
       * @param path The <code>Path</code> to animate values along.
       * @return An ObjectAnimator object that is set up to animate along <code>path</code>.
       */
      @NonNull
      public static ObjectAnimator ofObject(Object target, String propertyName,
              @Nullable TypeConverter<PointF, ?> converter, Path path) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofObject(propertyName, converter, path);
          return ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between Object values. A single
       * value implies that that value is the one being animated to, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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).
       *
       * <p><strong>Note:</strong> The values are stored as references to the original
       * objects, which means that changes to those objects after this method is called will
       * affect the values on the animator. If the objects will be mutated externally after
       * this method is called, callers should pass a copy of those objects instead.
       *
       * @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.
       */
      @NonNull
      @SafeVarargs
      public static <T, V> ObjectAnimator ofObject(T target, Property<T, V> property,
              TypeEvaluator<V> evaluator, V... values) {
          ObjectAnimator anim = new ObjectAnimator(target, property);
          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, in which case the start value
       * will be derived from the property being animated and the target object when {@link #start()}
       * is called for the first time. Two values imply 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).
       * This variant supplies a <code>TypeConverter</code> to convert from the animated values to the
       * type of the property. If only one value is supplied, the <code>TypeConverter</code> must be a
       * {@link android.animation.BidirectionalTypeConverter} to retrieve the current value.
       *
       * <p><strong>Note:</strong> The values are stored as references to the original
       * objects, which means that changes to those objects after this method is called will
       * affect the values on the animator. If the objects will be mutated externally after
       * this method is called, callers should pass a copy of those objects instead.
       *
       * @param target The object whose property is to be animated.
       * @param property The property being animated.
       * @param converter Converts the animated object to the Property type.
       * @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.
       */
      @NonNull
      @SafeVarargs
      public static <T, V, P> ObjectAnimator ofObject(T target, Property<T, P> property,
              TypeConverter<V, P> converter, TypeEvaluator<V> evaluator, V... values) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofObject(property, converter, evaluator,
                  values);
          return ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates a property along a <code>Path</code>.
       * A <code>Path</code></> animation moves in two dimensions, animating coordinates
       * <code>(x, y)</code> together to follow the line. This variant animates the coordinates
       * in a <code>PointF</code> to follow the <code>Path</code>. If <code>property</code>
       * uses a type other than <code>PointF</code>, <code>converter</code> can be used to change
       * from <code>PointF</code> to the type associated with the <code>Property</code>.
       *
       * <p>The PointF passed to <code>converter</code> or <code>property</code>, if
       * <code>converter</code> is <code>null</code>, is reused on each animation frame and should
       * not be stored by the setter or TypeConverter.</p>
       *
       * @param target The object whose property is to be animated.
       * @param property The property being animated. Should not be null.
       * @param converter Converts a PointF to the type associated with the setter. May be
       *                  null if conversion is unnecessary.
       * @param path The <code>Path</code> to animate values along.
       * @return An ObjectAnimator object that is set up to animate along <code>path</code>.
       */
      @NonNull
      public static <T, V> ObjectAnimator ofObject(T target, @NonNull Property<T, V> property,
              @Nullable TypeConverter<PointF, V> converter, Path path) {
          PropertyValuesHolder pvh = PropertyValuesHolder.ofObject(property, converter, path);
          return ofPropertyValuesHolder(target, pvh);
      }
  
      /**
       * Constructs and returns an ObjectAnimator that animates between the sets of values specified
       * in <code>PropertyValueHolder</code> 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 <code>setName()</code>, where <code>name</code> is the name of
       * the property passed in as the <code>propertyName</code> 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.
       */
      @NonNull
      public static ObjectAnimator ofPropertyValuesHolder(Object target,
              PropertyValuesHolder... values) {
          ObjectAnimator anim = new ObjectAnimator();
          anim.setTarget(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);
          }
      }
  
      /**
       * autoCancel controls whether an ObjectAnimator will be canceled automatically
       * when any other ObjectAnimator with the same target and properties is started.
       * Setting this flag may make it easier to run different animators on the same target
       * object without having to keep track of whether there are conflicting animators that
       * need to be manually canceled. Canceling animators must have the same exact set of
       * target properties, in the same order.
       *
       * @param cancel Whether future ObjectAnimators with the same target and properties
       * as this ObjectAnimator will cause this ObjectAnimator to be canceled.
       */
      public void setAutoCancel(boolean cancel) {
          mAutoCancel = cancel;
      }
  
      private boolean hasSameTargetAndProperties(@Nullable Animator anim) {
          if (anim instanceof ObjectAnimator) {
              PropertyValuesHolder[] theirValues = ((ObjectAnimator) anim).getValues();
              if (((ObjectAnimator) anim).getTarget() == getTarget() &&
                      mValues.length == theirValues.length) {
                  for (int i = 0; i < mValues.length; ++i) {
                      PropertyValuesHolder pvhMine = mValues[i];
                      PropertyValuesHolder pvhTheirs = theirValues[i];
                      if (pvhMine.getPropertyName() == null ||
                              !pvhMine.getPropertyName().equals(pvhTheirs.getPropertyName())) {
                          return false;
                      }
                  }
                  return true;
              }
          }
          return false;
      }
  
      @Override
      public void start() {
          AnimationHandler.getInstance().autoCancelBasedOn(this);
          if (DBG) {
              Log.d(LOG_TAG, "Anim target, duration: " + getTarget() + ", " + getDuration());
              for (int i = 0; i < mValues.length; ++i) {
                  PropertyValuesHolder pvh = mValues[i];
                  Log.d(LOG_TAG, "   Values[" + i + "]: " +
                      pvh.getPropertyName() + ", " + pvh.mKeyframes.getValue(0) + ", " +
                      pvh.mKeyframes.getValue(1));
              }
          }
          super.start();
      }
  
      boolean shouldAutoCancel(AnimationHandler.AnimationFrameCallback anim) {
          if (anim == null) {
              return false;
          }
  
          if (anim instanceof ObjectAnimator) {
              ObjectAnimator objAnim = (ObjectAnimator) anim;
              if (objAnim.mAutoCancel && hasSameTargetAndProperties(objAnim)) {
                  return true;
              }
          }
          return false;
      }
  
      /**
       * This function is called immediately before processing the first animation
       * frame of an animation. If there is a nonzero <code>startDelay</code>, 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.
       *
       *  <p>Overriders of this method should call the superclass method to cause
       *  internal mechanisms to be set up correctly.</p>
       */
      @CallSuper
      @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.
              final Object target = getTarget();
              if (target != null) {
                  final int numValues = mValues.length;
                  for (int i = 0; i < numValues; ++i) {
                      mValues[i].setupSetterAndGetter(target);
                  }
              }
              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
       * <code>ObjectAnimator.ofInt(target, propertyName, 0, 10).setDuration(500).start()</code>.
       */
      @Override
      @NonNull
      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
       */
      @Nullable
      public Object getTarget() {
          return mTarget == null ? null : mTarget.get();
      }
  
      @Override
      public void setTarget(@Nullable Object target) {
          final Object oldTarget = getTarget();
          if (oldTarget != target) {
              if (isStarted()) {
                  cancel();
              }
              mTarget = target == null ? null : new WeakReference<Object>(target);
              // New target should cause re-initialization prior to starting
              mInitialized = false;
          }
      }
  
      @Override
      public void setupStartValues() {
          initAnimation();
  
          final Object target = getTarget();
          if (target != null) {
              final int numValues = mValues.length;
              for (int i = 0; i < numValues; ++i) {
                  mValues[i].setupStartValue(target);
              }
          }
      }
  
      @Override
      public void setupEndValues() {
          initAnimation();
  
          final Object target = getTarget();
          if (target != null) {
              final int numValues = mValues.length;
              for (int i = 0; i < numValues; ++i) {
                  mValues[i].setupEndValue(target);
              }
          }
      }
  
      /**
       * 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 <code>end()</code>
       * function is called, to set the final value on the property.
       *
       * <p>Overrides of this method must call the superclass to perform the calculation
       * of the animated value.</p>
       *
       * @param fraction The elapsed fraction of the animation.
       */
      @CallSuper
      @Override
      void animateValue(float fraction) {
          final Object target = getTarget();
          if (mTarget != null && target == null) {
              // We lost the target reference, cancel and clean up. Note: we allow null target if the
              /// target has never been set.
              cancel();
              return;
          }
  
          super.animateValue(fraction);
          int numValues = mValues.length;
          for (int i = 0; i < numValues; ++i) {
              mValues[i].setAnimatedValue(target);
          }
      }
  
      @Override
      boolean isInitialized() {
          return mInitialized;
      }
  
      @Override
      public ObjectAnimator clone() {
          final ObjectAnimator anim = (ObjectAnimator) super.clone();
          return anim;
      }
  
      @Override
      @NonNull
      public String toString() {
          String returnVal = "ObjectAnimator@" + Integer.toHexString(hashCode()) + ", target " +
              getTarget();
          if (mValues != null) {
              for (int i = 0; i < mValues.length; ++i) {
                  returnVal += "\n    " + mValues[i].toString();
              }
          }
          return returnVal;
      }
  }
  