我有一个 UIImageView sliderPump，我通过一个接一个地调用两个方法从屏幕的右侧移动到左侧无限次:
-(void)pumpGoesRight
{
if (slide)
{
[UIView animateWithDuration:0.8 animations:^
{
[sliderPump setFrame:CGRectMake(sliderPump.frame.origin.x+235, sliderPump.frame.origin.y, sliderPump.frame.size.width, sliderPump.frame.size.height)];
} completion:^(BOOL finished)
{
[self pumpGoesLeft];
}];
}
else
return;
}
-(void)pumpGoesLeft
{
if (slide)
{
[UIView animateWithDuration:0.8 animations:^
{
[sliderPump setFrame:CGRectMake(sliderPump.frame.origin.x-235, sliderPump.frame.origin.y, sliderPump.frame.size.width, sliderPump.frame.size.height)];
} completion:^(BOOL finished)
{
[self pumpGoesRight];
}];
[self performSelector:@selector(pumpGoesRight) withObject:nil afterDelay:0.8];
}
else
return;
}
然后我使用这段代码找出 UIImageView sliderPump 的 X 位置并停止动画:
-(void)stop
{
slide = NO;
NSLog(@"Slide Pump position: %f", sliderPump.layer.frame.origin.x);
[self.view.layer removeAllAnimations];
}
问题是，当我调用 stop 方法时，我想得到 sliderPump 的当前位置，但我得到的是 sliderPimp 的最终位置动画结束，即使动画还没有完成。我怎样才能得到框架的当前位置？谢谢!
最佳答案
你应该使用表现层。
NSLog(@"Slide Pump position: %f", [sliderPump.layer.presentationLayer frame].origin.x);
关于ios - Objective-C: block 中的动画，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/28817384/