如何逆时针旋转Imageview

Question

我使用以下代码完全旋转图像顺时针

       - (void) runSpinAnimationOnView:(UIView*)view duration:(CGFloat)duration         rotations:      (CGFloat)rotations repeat:(float)repeat;
  {
   CABasicAnimation* rotationAnimation;
   rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
       rotationAnimation.toValue = [NSNumber numberWithFloat: rotations * 2.0 /* full rotation*/ * rotations * duration ];
    rotationAnimation.duration = duration;
    rotationAnimation.cumulative = YES;
    rotationAnimation.repeatCount = repeat;
    [view.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];
    } 

并致电

          [self runSpinAnimationOnView:_cycleImage duration:0.1 rotations:M_PI_2 repeat:13];

它顺时针旋转图像并锁定很好，但如何旋转相同的图像和相同的动画和持续时间逆时针。 请帮忙

Answer 1

对于逆时针旋转，请将rotationAnimation.toValue设置为负值， 例如

rotationAnimation.toValue = @(-2.0*M_PI);

进行一次完整的逆时针旋转。