iPhone UIImageView 旋转

Question

谁能告诉我如何以圆周运动旋转图像

Answer 1

您可以将 View 旋转一定的弧度，无论它是小于完整旋转还是完整旋转的许多倍，而不必将旋转分割成多个部分。例如，以下代码将每秒旋转一次 View 指定的秒数。您可以轻松地将其修改为将 View 旋转一定数量的旋转或一定数量的弧度。

- (void) runSpinAnimationWithDuration:(CGFloat) duration;
{
    CABasicAnimation* rotationAnimation;
    rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
    rotationAnimation.toValue = [NSNumber numberWithFloat: M_PI * 2.0 /* full rotation*/ * rotations * duration ];
    rotationAnimation.duration = duration;
    rotationAnimation.cumulative = YES;
    rotationAnimation.repeatCount = 1.0; 
    rotationAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut];

    [myView.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];
}