iphone - 带有旋转动画的 CALayer

Question

我屏蔽了这样一张图片:

UIView *maskImage; maskImage = [[UIView alloc] init];
maskImage.backgroundColor = UIColorFromRGB(FTRMaskColor);
maskImage.frame = newFrame;

CALayer *theLayer = [CALayer layer];
theLayer.contents = (id)[[UIImage imageNamed:@"image.png"] CGImage];
theLayer.frame = newFrame;

maskImage.layer.mask = theLayer;

它工作正常，但主要问题是如果我想旋转我的 Ipad， View 或层的旋转动画(我不太确定)不起作用。它在没有动画的情况下旋转。你能帮忙吗？

Answer 1

旋转CALayer:

NSNumber *rotationAtStart = [myLayer valueForKeyPath:@"transform.rotation"];
CATransform3D myRotationTransform = CATransform3DRotate(myLayer.transform, myRotationAngle, 0.0, 0.0, 1.0);
myLayer.transform = myRotationTransform;        
CABasicAnimation *myAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation"];
myAnimation.duration = kMyAnimationDuration;
myAnimation.fromValue = rotationAtStart;
myAnimation.toValue = [NSNumber numberWithFloat:([rotationAtStart floatValue] + myRotationAngle)];
[myLayer addAnimation:myAnimation forKey:@"transform.rotation"];

myRotationAngle 应该以弧度为单位。逆时针旋转使用负值，顺时针旋转使用正值。