IPhone：核心动画：在y轴上展开视图

Question

我正在学习核心动画，根据我的任务，我必须线性地在y轴上展开/折叠图层我有以下代码

CABasicAnimation *shrinkAnimation;
shrinkAnimation = [CABasicAnimation animationWithKeyPath:@"transform"]; //use transform instead of bounds.size
shrinkAnimation.repeatCount = 1;
shrinkAnimation.autoreverses = NO;
[shrinkAnimation setDuration:1.5];
shrinkAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn]; 
shrinkAnimation.toValue = [NSValue valueWithCATransform3D:CATransform3DScale(myView.layer.transform, 1, 0.1, 1.0)];
[myView.layer addAnimation:shrinkAnimation forKey:@"bounds.size"];

但这里的问题是图层同时从两端收缩/扩展，你能帮助我在一个方向上扩展/折叠。

提前致谢

此致

ANKIT

Answer 1

将图层的anchor point设置为0,0或1,1或其他一些值，以使您想要的边缘不会移动。

myView.layer.anchorPoint = CGPointMake(0,0);