小编use*_*467的帖子

我有一个CALayer,我想展示然后隐藏.

CALayer *layerOne = [CALayer layer];
[layerOne addSublayer:textOne];
layerOne.frame = CGRectMake(0, 0, size.width, size.height);
[layerOne setMasksToBounds:YES];
layerOne.opacity = 0.0;

CABasicAnimation *animationOne = [CABasicAnimation animationWithKeyPath:@"opacity"];
[animationOne setDuration:0];
[animationOne setFromValue:[NSNumber numberWithFloat:0.0]];
[animationOne setToValue:[NSNumber numberWithFloat:1.0]];
[animationOne setBeginTime:3];
[animationOne setRemovedOnCompletion:NO];
[animationOne setFillMode:kCAFillModeForwards];
[layerOne addAnimation:animationOne forKey:@"animateOpacity"];

此代码工作成功,3秒后出现layerOne.

但我想隐藏这一层,所以我添加了这个:

CABasicAnimation *animationTwo = [CABasicAnimation animationWithKeyPath:@"opacity"];
[animationTwo setDuration:0];
[animationTwo setFromValue:[NSNumber numberWithFloat:1.0]];
[animationTwo setToValue:[NSNumber numberWithFloat:0.0]];
[animationTwo setBeginTime:6];
[animationTwo setRemovedOnCompletion:NO];
[animationTwo setFillMode:kCAFillModeForwards];
[layerOne addAnimation:animationTwo forKey:@"animateOpacity"];

它不起作用.layerOne 3秒后不出现.它刚刚闪过第二个6并消失.它似乎是阻止第一个动画的第二个动画,只有第二个动画正在进行.

我做错了什么？