Android属性动画设置中心点
public static void rotateIn(RelativeLayout layout, long delay) {
ObjectAnimator rotate = ObjectAnimator.ofFloat(layout, "rotation", -180f, 0f);
layout.setPivotX(layout.getWidth()/2);
layout.setPivotY(layout.getHeight());
//显示的调用invalidate
layout.invalidate();
rotate.setDuration(500);
rotate.setStartDelay(delay);
rotate.addListener(new MyAnimationListener2());
rotate.start();
}
