CABasicAnimation will not animate my opacity

Question

I am using CABasicAnimation to try and animate my root level views layer and it won't animate. The animation is happening in about 0.2 NOT the 77.0 I have below.

CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"opacity"];
animation.beginTime = 1.0;
animation.duration = 77.0;
animation.fromValue = [NSNumber numberWithFloat:0.0f];
animation.toValue = [NSNumber numberWithFloat:1.0f];
animation.removedOnCompletion = NO;
animation.fillMode = kCAFillModeBoth;
animation.additive = NO;

[self.layer addAnimation:animation forKey:@"show-anim" ];

Answer 1

您需要相对于当前媒体时间设置开始时间：

    animation.beginTime = CACurrentMediaTime() + 1;