Android属性动画特点详解

/*
属性动画的特点：动画效果会改变控件的位置.且开启动画的是动画对象,而不是控件对象.
    只有旋转的属性动画是经常用的,注意参数.
    注意:这些方法都是安卓在3.0以后出现的新特性,所以要把AndroidManifest.xml里的android:minSdkVersion值修改为11以上
*/
//注释后面有222的暂时不用管.
public class MainActivity extends AppCompatActivity implements View.OnClickListener {

  private ImageButton imageView;
  private Button alpha_bt;
  private Button rotationY_bt;
  private Button scaleX_bt;
  private Button translationX_bt;
  private Button AnimatorSet_bt;


  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
//    对控件进行初始化
    init();

//   此处用的是xml的形式.引用在Xml里的属性动画资源. AnimatorInflater.loadAnimator(上下文,R.animator..)222
    Animator Xmlanimator = AnimatorInflater.loadAnimator(this, R.animator.objectanimator);
//   把要做动画控件对象放进去.Animator.setTarget(View对象);222
    Xmlanimator.setTarget(imageView);
//   开启动画.Animator.start.222
    Xmlanimator.start();

  }

  // 对于控件进行初始化
  private void init() {
    //找到ImageView控件对象
    imageView = (ImageButton) findViewById(R.id.animation_iv);
    //找到Button控件对象.
    alpha_bt = (Button) findViewById(R.id.alpha_bt);
    rotationY_bt = (Button) findViewById(R.id.rotationY_bt);
    scaleX_bt = (Button) findViewById(R.id.scaleX_bt);
    translationX_bt = (Button) findViewById(R.id.translationY_bt);
    AnimatorSet_bt = (Button) findViewById(R.id.AnimatorSet_bt);
    //为button设置点击事件
    alpha_bt.setOnClickListener(this);
    rotationY_bt.setOnClickListener(this);
    scaleX_bt.setOnClickListener(this);
    translationX_bt.setOnClickListener(this);
    AnimatorSet_bt.setOnClickListener(this);

  }

  /**
   * 根据点击事件类型.调用控件做属性动画的
   *
   * @param view
   */
  @Override
  public void onClick(View view) {
    switch (view.getId()) {
      case R.id.alpha_bt:
        //做透明动画,参数1:View,代表你要修改那个控件的属性. 参数2:propertyName代表实现什么样子的动画:"alpha",String类型.
        //参数3:float... values,控件修改的参数,new float[]{0.0f, 0.2f, 0.4f, 0.6f, 0.8f, 1.0f}
        ObjectAnimator alpha = ObjectAnimator.ofFloat(imageView, "alpha", new float[]{0.0f, 0.2f, 0.4f, 0.6f, 0.8f, 1.0f});
        //设置动画执行时长.setDuration
        alpha.setDuration(2000);
        //设置动画执行的模式setRepeatMode,参数用ObjectAnimator引用.
        alpha.setRepeatMode(ObjectAnimator.RESTART);
        //设置动画执行的次数.setRepeatCount
        alpha.setRepeatCount(1);
        //使用ObjectAnimator对象开启动画.
        alpha.start();

        break;
      case R.id.rotationY_bt:
        //做旋转动画,"rotationY".rotationX,rotation new float[]{90f, 180f, 270f, 360f}
        ObjectAnimator rotatiOnY= ObjectAnimator.ofFloat(imageView, "rotationY", new float[]{90f, 180f, 270f, 360f});
        rotationY.setDuration(2000);
        rotationY.setRepeatMode(ObjectAnimator.RESTART);
        rotationY.setRepeatCount(1);
        rotationY.start();
        break;
      case R.id.scaleX_bt:
        //做缩放动画,scaleX,scaleY new float[]{1f, 2f, 3f, 4f, 5f, 6f,1f}
        ObjectAnimator scaleX = ObjectAnimator.ofFloat(imageView, "scaleX", new float[]{1f, 2f, 3f, 4f, 5f, 6f, 1f});
        scaleX.setDuration(2000);
        scaleX.setRepeatMode(ObjectAnimator.RESTART);
        scaleX.setRepeatCount(1);
        scaleX.start();

        break;
      case R.id.translationY_bt:
        //做平移动画,translationY,translationX new float[]{10f, 20f, 30f, 40f, 60f, 80f}
        ObjectAnimator translatiOnY= ObjectAnimator.ofFloat(imageView, "translationY", new float[]{10f, 20f, 30f, 40f, 60f, 80f});
        translationY.setDuration(2000);
        translationY.setRepeatMode(ObjectAnimator.RESTART);
        translationY.setRepeatCount(1);
        translationY.start();

        //做动画集合AnimatorSet,分别创建两个动画对象.注意playTogether(动画对象...)和playSequentially的区别.最后开启动画.start
      case R.id.AnimatorSet_bt:
        AnimatorSet set = new AnimatorSet();
        ObjectAnimator oa = ObjectAnimator.ofFloat(imageView, "translationX", new float[]{10f, 20f, 30f, 40f, 60f, 80f});
        oa.setDuration(3000);
        ObjectAnimator oa2 = ObjectAnimator.ofFloat(imageView, "translationY", new float[]{-10f, -20f, -30f, -40f, -60f, -80f});
        oa2.setDuration(3000);
        set.playTogether(oa, oa2);
        set.start();
        break;
      default:
        break;
    }
  }

}