iphone - CALayer 的动画结束回调？

Question

我想知道 CALayer 中动画的回调在哪里(或者是否有任何东西)。具体来说，对于隐式动画，例如更改框架、位置等。在 UIView 中，您可以执行以下操作:

[UIView beginAnimations:@"SlideOut" context:nil];
[UIView setAnimationDuration:.3];
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:@selector(animateOut:finished:context:)];
CGRect frame = self.frame;
frame.origin.y = 480;
self.frame = frame;
[UIView commitAnimations];

具体来说，setAnimationDidStopSelector 是我想要的 CALayer 动画。有这样的事吗？

TIA。

Answer 1

您可以使用 CATransaction，它有一个完成 block 处理程序。

[CATransaction begin];
CABasicAnimation *pathAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
[pathAnimation setDuration:1];
[pathAnimation setFromValue:[NSNumber numberWithFloat:0.0f]];    
[pathAnimation setToValue:[NSNumber numberWithFloat:1.0f]];
[CATransaction setCompletionBlock:^{_lastPoint = _currentPoint; _currentPoint = CGPointMake(_lastPoint.x + _wormStepHorizontalValue, _wormStepVerticalValue);}];
[_pathLayer addAnimation:pathAnimation forKey:@"strokeEnd"];
[CATransaction commit];