Android缩放动画

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public void startAnimation(Animation animation)

• 执行动画，参数可以是各种动画的对象，Animation的多态，也可以是组合动画，后面会有。

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4个参数构造方法

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/**

 * Constructor to use when building a ScaleAnimation from code

 * 

 * @param fromX Horizontal scaling factor to apply at the start of the animation

 * @param toX Horizontal scaling factor to apply at the end of the animation

 * @param fromY Vertical scaling factor to apply at the start of the animation

 * @param toY Vertical scaling factor to apply at the end of the animation

 */

public ScaleAnimation(float fromX, float toX, float fromY, float toY) {

    mResources = null;

    mFromX = fromX;

    mToX = toX;

    mFromY = fromY;

    mToY = toY;

    mPivotX = 0;

    mPivotY = 0;

}

用法

public void scale(View view) {

    // 创建缩放的动画对象

    ScaleAnimation sa = new ScaleAnimation(0f,1.0f,0f,1.0f);

    // 设置动画播放的时间

    sa.setDuration(1000);

    // 开始播放动画

    iv.startAnimation(sa);

}

效果

以图片左上角为原点，从没有，放大到图片原大小

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6个参数构造方法

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   /**

    * Constructor to use when building a ScaleAnimation from code

    * 

    * @param fromX Horizontal scaling factor to apply at the start of the animation

    * @param toX Horizontal scaling factor to apply at the end of the animation

    * @param fromY Vertical scaling factor to apply at the start of the animation

    * @param toY Vertical scaling factor to apply at the end of the animation

    * @param pivotX The X coordinate of the point about which the object is being scaled, specified as an absolute number where 0 is the left edge. (This point remains fixed while the object changes size.)

    * @param pivotY The Y coordinate of the point about which the object is being scaled, specified as an absolute number where 0 is the top edge. (This point remains fixed while the object changes size.)

    */

   public ScaleAnimation(float fromX, float toX, float fromY, float toY, float pivotX, float pivotY) {

       mResources = null;

       mFromX = fromX;

       mToX = toX;

       mFromY = fromY;

       mToY = toY;



       mPivotXType = ABSOLUTE;

       mPivotYType = ABSOLUTE;

       mPivotXValue = pivotX;

       mPivotYValue = pivotY;

       initializePivotPoint();

   }

• 前4个参数和上面的用法一样，后两个参数是设置图片缩放的原点，四个参数的构造默认将这两个参数都设置了0，所以是在图片左上角开始缩放

用法

ScaleAnimation sa = new ScaleAnimation(0f, 1.0f, 0f, 1.0f, iv.getWidth() / 2, iv.getHeight() / 2);

// 设置动画播放的时间

sa.setDuration(1000);

// 开始播放动画

iv.startAnimation(sa);

效果

以图片的中心为原点，从没有放大到图片原大小

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8个参数构造方法

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  /**

    * Constructor to use when building a ScaleAnimation from code

    * 

    * @param fromX Horizontal scaling factor to apply at the start of the animation

    * @param toX Horizontal scaling factor to apply at the end of the animation

    * @param fromY Vertical scaling factor to apply at the start of the animation

    * @param toY Vertical scaling factor to apply at the end of the animation

    * @param pivotXType Specifies how pivotXValue should be interpreted. One of Animation.ABSOLUTE, Animation.RELATIVE_TO_SELF, or Animation.RELATIVE_TO_PARENT.

    * @param pivotXValue The X coordinate of the point about which the object is being scaled, specified as an absolute number where 0 is the left edge. (This point remains fixed while the object changes size.) This value can either be an absolute number if pivotXType is ABSOLUTE, or a percentage (where 1.0 is 100%) otherwise.

    * @param pivotYType Specifies how pivotYValue should be interpreted. One of Animation.ABSOLUTE, Animation.RELATIVE_TO_SELF, or Animation.RELATIVE_TO_PARENT.

    * @param pivotYValue The Y coordinate of the point about which the object is being scaled, specified as an absolute number where 0 is the top edge. (This point remains fixed while the object changes size.) This value can either be an absolute number if pivotYType is ABSOLUTE, or a percentage (where 1.0 is 100%) otherwise.

    */

   public ScaleAnimation(float fromX, float toX, float fromY, float toY, int pivotXType, float pivotXValue, int pivotYType, float pivotYValue) {

       mResources = null;

       mFromX = fromX;

       mToX = toX;

       mFromY = fromY;

       mToY = toY;



       mPivotXValue = pivotXValue;

       mPivotXType = pivotXType;

       mPivotYValue = pivotYValue;

       mPivotYType = pivotYType;

       initializePivotPoint();

   }

用法

// 创建缩放的动画对象

ScaleAnimation sa = new ScaleAnimation(0f, 1.0f, 0f, 1.0f, ScaleAnimation.RELATIVE_TO_SELF, 0.5f, ScaleAnimation.RELATIVE_TO_SELF, 0.5f);

// 设置动画播放的时间

sa.setDuration(1000);

// 开始播放动画

iv.startAnimation(sa);

• 和上面6个参数的相比只是多了第5和第7个参数，分别设置他们的类型，注释里面已经说明了，可以设置Animation.ABSOLUTE、Animation.RELATIVE_TO_SELF、Animation.RELATIVE_TO_PARENT类型

效果

效果和上面一样，以图片的中心为原点，从没有放大到图片原大小。

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设置动画重复播放的次数的方法

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/**

 * Sets how many times the animation should be repeated. If the repeat

 * count is 0, the animation is never repeated. If the repeat count is

 * greater than 0 or {@link #INFINITE}, the repeat mode will be taken

 * into account. The repeat count is 0 by default.

 *

 * @param repeatCount the number of times the animation should be repeated

 * @attr ref android.R.styleable#Animation_repeatCount

 */

public void setRepeatCount(int repeatCount) {

    if (repeatCount < 0) {

        repeatCount = INFINITE;

    }

    mRepeatCount = repeatCount;