property动画

最新推荐文章于 2022-08-25 17:24:35 发布

原创最新推荐文章于 2022-08-25 17:24:35 发布 · 213 阅读

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CC 4.0 BY-SA版权

本文介绍如何使用Android中的ObjectAnimator实现各种动画效果，包括单个动画、连续动画、从XML加载动画、一个动画改变多个属性值、View的多个属性动画、自定义Evaluator及关键帧动画。

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/*
 * 单个动画
 */
public void testObjectAnimator(View btnView) {
   float width = m_tv.getWidth();
   if (m_tv.getX() == 0) {
      ObjectAnimator translationRight = ObjectAnimator.ofFloat(m_tv, "X",
            width);
      translationRight.setDuration(1500);
      translationRight.start();
   } else {
      ObjectAnimator translationLeft = ObjectAnimator.ofFloat(m_tv, "X",
            0f);
      translationLeft.setDuration(1500);
      translationLeft.start();
   }
}




/*
 * 连续动画
 */
public void testAnimationSet(View v) {
   float width = m_tv.getWidth();
   float height = m_tv.getHeight();
   ObjectAnimator translationRight = ObjectAnimator.ofFloat(m_tv, "X", width);
   ObjectAnimator translationLeft = ObjectAnimator.ofFloat(m_tv, "X", 0f);
   ObjectAnimator translationDown = ObjectAnimator.ofFloat(m_tv, "Y",height);
   ObjectAnimator translationUp = ObjectAnimator.ofFloat(m_tv, "Y", 0);

   AnimatorSet as = new AnimatorSet();
   as.play(translationRight).before(translationLeft);
   as.play(translationRight).with(translationDown);
   as.play(translationLeft).with(translationUp);

   // 和上边四句等效，另一种写法
       /*
   AnimatorSet as = new AnimatorSet();
   as.playTogether(translationRight, translationDown);
   as.playSequentially(translationRight, translationLeft);
   as.playTogether(translationLeft, translationUp);
       */
   as.setDuration(1500);
   as.start();
}




从xml中加载动画 animator
<?xml version="1.0" encoding="utf-8"?>
<!-- /res/animator/fadein.xml -->
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:ordering="sequentially" >

    <objectAnimator
        android:duration="2000"
        android:interpolator="@android:interpolator/accelerate_cubic"
        android:propertyName="alpha"
        android:valueFrom="1"
        android:valueTo="0"
        android:valueType="floatType" />
    <objectAnimator
        android:duration="2000"
        android:interpolator="@android:interpolator/accelerate_cubic"
        android:propertyName="alpha"
        android:valueFrom="0"
        android:valueTo="1"
        android:valueType="floatType" />

</set>

/*
 * XML，便于代码重用
 */
public void testAnimationXML(View bView) {
   m_tv.setAlpha(1f);
   AnimatorSet set = (AnimatorSet) AnimatorInflater.loadAnimator(this,
         R.animator.fadein);
   set.setTarget(m_tv);
   set.start();





一个动画改变多个属性值
/*
 * 一个动画改变多个属性值
 */
public void testPropertyValuesHolder(View v) {
   m_tv.setAlpha(1f);
   float h = m_tv.getHeight();
   float w = m_tv.getWidth();
   float x = m_tv.getX();
   float y = m_tv.getY();

   m_tv.setX(w);
   m_tv.setY(h);
   PropertyValuesHolder pvhX = PropertyValuesHolder.ofFloat("x", x);
   PropertyValuesHolder pvhY = PropertyValuesHolder.ofFloat("y", y);

   ObjectAnimator oa = ObjectAnimator.ofPropertyValuesHolder(m_tv, pvhX,
         pvhY);
   oa.setDuration(3000);
   // oa.setInterpolator(new AccelerateDecelerateInterpolator());
   oa.setInterpolator(new BounceInterpolator());
   oa.start();
}



一个View的多个属性进行动画
/*
 * 一个View的多个属性进行动画，3.1中引入，对多属性动画进行了优化
 */
@TargetApi(Build.VERSION_CODES.HONEYCOMB_MR1)
public void testViewPropertyAnimator(View v) {
   m_tv.setAlpha(1f);
   float h = m_tv.getHeight();
   float w = m_tv.getWidth();
   float x = m_tv.getX();
   float y = m_tv.getY();

   m_tv.setX(w);
   m_tv.setY(h);

   ViewPropertyAnimator vpa = m_tv.animate().x(x).y(y);

   vpa.setDuration(1500);
   vpa.setInterpolator(new BounceInterpolator());
}



/*
 * 自定义Evaluator
 */
public void testTypeEvaluator(View v) {
   m_tv.setAlpha(1f);

   float h = m_tv.getHeight();
   float w = m_tv.getWidth();
   float x = m_tv.getX();
   float y = m_tv.getY();

   ObjectAnimator tea = ObjectAnimator.ofObject(m_atv, "point",
         new MyPointEvaluator(), new PointF(w, h), new PointF(x, y));
   tea.setDuration(2000);
   tea.setInterpolator(new OvershootInterpolator());
   tea.start();

}
import android.animation.TypeEvaluator;
import android.graphics.PointF;

public class MyPointEvaluator implements TypeEvaluator<PointF> {
   public PointF evaluate(float fraction, PointF startValue, PointF endValue) {
      PointF startPoint = (PointF) startValue;
      PointF endPoint = (PointF) endValue;
      return new PointF(
            startPoint.x + fraction * (endPoint.x - startPoint.x),
            startPoint.y + fraction * (endPoint.y - startPoint.y));
   }
}





/*
 * 关键帧
 */
public void testKeyFrames(View v) {
   float h = m_tv.getHeight();
   float w = m_tv.getWidth();
   float x = m_tv.getX();
   float y = m_tv.getY();

   Keyframe kf0 = Keyframe.ofFloat(0.2f, 360);
   Keyframe kf1 = Keyframe.ofFloat(0.5f, 30);
   Keyframe kf2 = Keyframe.ofFloat(0.8f, 1080);
   Keyframe kf3 = Keyframe.ofFloat(1f, 0);
   PropertyValuesHolder pvhRotation = PropertyValuesHolder.ofKeyframe(
         "rotation", kf0, kf1, kf2, kf3);

   PropertyValuesHolder pvhX = PropertyValuesHolder.ofFloat("x", w, x);
   PropertyValuesHolder pvhY = PropertyValuesHolder.ofFloat("y", h, y);

   ObjectAnimator anim = ObjectAnimator.ofPropertyValuesHolder(m_tv,
         pvhRotation, pvhX, pvhY);
   anim.setDuration(2000);
   anim.start();
}