CALayer动画缩放动画效果问题

在用CABasicAnimation实现视图缩放效果的时候，如果不加上下面两句会入到视图缩放动画后又恢复原大小的问题

animGroup.removedOnCompletion =NO;
animGroup.fillMode =kCAFillModeForwards;

另备注一下常用的animationWithKeyPath

bounds

opacity

position

transform.rotation.z/y/x

transform.scale

今天看一个源码，发现还可以设置

borderColor

CABasicAnimation *borderAnimation = [CABasicAnimation animationWithKeyPath:@"borderColor"];
borderAnimation.fromValue = (id)[UIColor clearColor].CGColor;
borderAnimation.toValue = (id)stroke.CGColor;
borderAnimation.duration = 0.5f;
[view.layer addAnimation:borderAnimation forKey:nil]