实现 图片 X，Y， Z 三轴 持续旋转动画
直接上代码
// 如果是y, 则transform.rotation.z改为transform.rotation.y, x轴旋转也是一样
CABasicAnimation* rotationAnimation;
rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
rotationAnimation.toValue = [NSNumber numberWithFloat: (M_PI * 2.0)];
rotationAnimation.duration = 3.0;
rotationAnimation.removedOnCompletion = NO;
rotationAnimation.repeatCount = MAXFLOAT;
rotationAnimation.fillMode = kCAFillModeForwards;
[self.imageView.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];
