1.难点：
- 无限循环：
ObjectAnimation.setRepeatCount(ValueAnimator.INFINITE);
- 匀速转动
ObjectAnimation.setInterpolator(new LinearInterpolator());
2.代码：
public static ObjectAnimator getRotateAnimation(View pView, boolean isClockWise, long duration, boolean isRepeat) {
int endAngle;
if (isClockWise) {
endAngle = 360;
} else {
endAngle = -360;
}
ObjectAnimator res = ObjectAnimator.ofFloat(pView, "rotation", 0, endAngle);
res.setDuration(duration);
res.setInterpolator(new LinearInterpolator());
if (isRepeat) {
res.setRepeatCount(ValueAnimator.INFINITE);
}
return res;
}
