我阅读并实现了Technical Q&A QA1673关于暂停层树中的所有动画,但我遇到了使用延迟参数的动画的问题.我可以暂停和恢复动画,但是当动画恢复时,任何与其相关的延迟的动画块似乎都会延迟图层树暂停的时间.因此,例如,如果其中一个块的延迟为1秒,并且图层树暂停3秒,则动画在恢复后会延迟4秒.我猜这与beginTime属性有关？任何帮助,将不胜感激.

// Pause and Resume methods,right from the technical Q&A
- (void)pauseAnimationsOnLayer:(CALayer *)layer
{
    CFTimeInterval pausedTime = [layer convertTime:CACurrentMediaTime() fromLayer:nil];
    layer.speed = 0.0;
    layer.timeOffset = pausedTime;
}
 
- (void)resumeAnimationsOnLayer:(CALayer *)layer
{
    CFTimeInterval pausedTime = [layer timeOffset];
    layer.speed = 1.0;
    layer.timeOffset = 0.0;
    layer.beginTime = 0;
    CFTimeInterval timeSincePause = [layer convertTime:CACurrentMediaTime() fromLayer:nil] - pausedTime;
    layer.beginTime = timeSincePause;
}
 
// Chained animations
- (void)animateNextPopup
{
    [UIView animateWithDuration:kRFPVictorySequenceStatePopupDuration
                     animations:^{
                         [_currentStateImageView setHidden:NO];
                         [_currentStateImageView setTransform:CGAffineTransformIdentity];
 
                     }
                     completion:^(BOOL finished) {
                         [UIView animateWithDuration:kRFPVictorySequenceStateSlideOffDuration
                                               delay:kRFPVictorySequenceStateVoteDelay
                                             options:UIViewAnimationOptionCurveEaseInOut
                                          animations:^{
                                              if (winnerIsDem) {
                                                  [_currentStateImageView setFrame:CGRectMake(-_currentStateImageView.frame.size.width,_currentStateImageView.frame.origin.y,_currentStateImageView.frame.size.width,_currentStateImageView.frame.size.height)];
                                              }
                                              else {
                                                  [_currentStateImageView setFrame:CGRectMake(1024,_currentStateImageView.frame.size.height)];
                                              }
                                          }
                                          completion:^(BOOL finished) {
                                              // Do some stuff
                                          }
                          ];
                     }
     ];
}