连续animation调用不起作用

我有一个button，调用animateWithDuration代码淡出图像，淡入淡出的文本和新的颜色，然后重置为正常。 animation需要几秒钟才能完成，效果很好。

然而！ 有一个问题：

有时候这个button会在animation结束之前再次被按下。 发生这种情况时，我希望当前animation停止并重新开始。

研究解决scheme不工作

根据我的阅读，解决scheme应该是简单的，只需导入QuartzCore并添加：

button.layer.removeAllAnimations() 

这确实删除了animation，但新的/第二个animation是完全搞砸了。 应该隐藏的图像不是，文本从不出现，颜色转换全部错误。 发生了什么！？！

 //Animate Finished feedback in footer bar func animateFinished(textToDisplay: String, footerBtn: UIButton, footerImg: UIImageView) { //Should cancel any current animation footerBtn.layer.removeAllAnimations() footerBtn.alpha = 0 footerBtn.setTitle(textToDisplay, forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Regular", size: 18) footerBtn.setTitleColor(UIColor(red: 255/255.0, green: 255/255.0, blue: 255/255.0, alpha: 1.0), forState: UIControlState.Normal) footerBtn.backgroundColor = UIColor(red: 217/255.0, green: 217/255.0, blue: 217/255.0, alpha: 1.0) UIView.animateWithDuration(0.5, delay: 0.0, options: nil, animations: { footerImg.alpha = 0.01 //Img fades out footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 163/255.0, blue: 00/255.0, alpha: 0.6) } , completion: { finished in UIView.animateWithDuration(0.5, delay: 0.0, options: nil, animations: { footerBtn.alpha = 1 //Text fades in footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 208/255.0, blue: 11/255.0, alpha: 0.6) } , completion: { finished in UIView.animateWithDuration(0.5, delay: 1.0, options: nil, animations: { footerBtn.alpha = 0.01 //Text fades out footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 173/255.0, blue: 00/255.0, alpha: 0.6) } , completion: { finished in UIView.animateWithDuration(0.5, delay: 0.0, options: nil, animations: { footerImg.alpha = 1 //Img fades in } , completion: { finished in footerBtn.backgroundColor = UIColor.clearColor() footerBtn.setTitleColor(UIColor(red: 55/255.0, green: 55/255.0, blue: 55/255.0, alpha: 1.0), forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Light", size: 18) footerBtn.setTitle("", forState: UIControlState.Normal) footerBtn.alpha = 1 //Completion blocks sets values back to norm }) }) }) }) }//End of animation 

@Shripadabuild议我切换到关键帧以获取更多可读代码。 下面的关键帧格式。 它没有解决animation中断问题。 如果你能解决嵌套或关键帧格式的问题，请发布！

 func animateFinished(textToDisplay: String, footerBtn: UIButton, footerImg: UIImageView) { //Should cancel any current animation footerBtn.layer.removeAllAnimations() footerBtn.alpha = 0 footerBtn.setTitle(textToDisplay, forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Regular", size: 18) footerBtn.setTitleColor(UIColor(red: 255/255.0, green: 255/255.0, blue: 255/255.0, alpha: 1.0), forState: UIControlState.Normal) //footerBtn.backgroundColor = UIColor(red: 217/255.0, green: 217/255.0, blue: 217/255.0, alpha: 1.0) UIView.animateKeyframesWithDuration(3.0 /*Total*/, delay:0.0, options: UIViewKeyframeAnimationOptions.CalculationModeLinear, animations: { UIView.addKeyframeWithRelativeStartTime(0.0, relativeDuration:0.10, animations:{ footerImg.alpha = 0.01 //Img fades out footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 103/255.0, blue: 00/255.0, alpha: 0.6) //Bg turns to green }) UIView.addKeyframeWithRelativeStartTime(0.10, relativeDuration:0.30, animations:{ footerBtn.alpha = 1 //Text and green bg fades in footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 173/255.0, blue: 11/255.0, alpha: 0.6) //BG turns greener }) UIView.addKeyframeWithRelativeStartTime(0.40, relativeDuration:0.50, animations:{ footerBtn.alpha = 0.01 //Text fades out & bg fade out }) }, completion: { finished in footerImg.alpha = 1 footerBtn.alpha = 1 footerBtn.backgroundColor = UIColor.clearColor() footerBtn.setTitleColor(UIColor(red: 55/255.0, green: 55/255.0, blue: 55/255.0, alpha: 1.0), forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Light", size: 18) footerBtn.setTitle("", forState: UIControlState.Normal) //Completion blocks sets values back to norm } ) }//End of 'Finished' animation 

Answer 1

我为你的animateFinished方法添加了一些print行，以便看看发生了什么：

 func animateFinished(textToDisplay: String, footerBtn: UIButton, footerImg: UIImageView) { //Should cancel any current animation print("Remove animations") footerBtn.layer.removeAllAnimations() print("Animations removed") footerBtn.alpha = 0 footerBtn.setTitle(textToDisplay, forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Regular", size: 18) footerBtn.setTitleColor(UIColor(red: 255/255.0, green: 255/255.0, blue: 255/255.0, alpha: 1.0), forState: UIControlState.Normal) //footerBtn.backgroundColor = UIColor(red: 217/255.0, green: 217/255.0, blue: 217/255.0, alpha: 1.0) print("Initial animation setup completed") UIView.animateKeyframesWithDuration(3.0 /*Total*/, delay:0.0, options: UIViewKeyframeAnimationOptions.CalculationModeLinear, animations: { UIView.addKeyframeWithRelativeStartTime(0.0, relativeDuration:0.10, animations:{ footerImg.alpha = 0.01 //Img fades out footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 103/255.0, blue: 00/255.0, alpha: 0.6) //Bg turns to green }) UIView.addKeyframeWithRelativeStartTime(0.10, relativeDuration:0.30, animations:{ footerBtn.alpha = 1 //Text and green bg fades in footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 173/255.0, blue: 11/255.0, alpha: 0.6) //BG turns greener }) UIView.addKeyframeWithRelativeStartTime(0.40, relativeDuration:0.50, animations:{ footerBtn.alpha = 0.01 //Text fades out & bg fade out }) }, completion: { finished in print("Completion block started") footerImg.alpha = 1 footerBtn.alpha = 1 footerBtn.backgroundColor = UIColor.clearColor() footerBtn.setTitleColor(UIColor(red: 55/255.0, green: 55/255.0, blue: 55/255.0, alpha: 1.0), forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Light", size: 18) footerBtn.setTitle("", forState: UIControlState.Normal) //Completion blocks sets values back to norm print("Completion block finished") } ) }//End of 'Finished' animation 

如果您允许animation运行完成，日志会显示如您所期望的那样：

 Remove animations Animations removed Initial animation setup completed Completion block started Completion block finished 

但是，如果在animation过程中点击button，您会看到：

 Remove animations Animations removed Initial animation setup completed Remove animations Animations removed Initial animation setup completed Completion block started Completion block finished Completion block started Completion block finished 

在第二次调用的初始设置完成之后， 在执行第二次animation之前 ， removeAllAnimations会导致完成块（用于第一次调用）被执行。 所以，例如，第二个animation中的button标题是“”。

修复相对简单：如果animation未完成，则不要执行完成块：

  completion: { finished in if (!finished) { return } print("Completion block started") footerImg.alpha = 1 footerBtn.alpha = 1 footerBtn.backgroundColor = UIColor.clearColor() footerBtn.setTitleColor(UIColor(red: 55/255.0, green: 55/255.0, blue: 55/255.0, alpha: 1.0), forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Light", size: 18) footerBtn.setTitle("", forState: UIControlState.Normal) print("Completion block finished") //Completion blocks sets values back to norm } 

此外，根据Shripada，您将需要从footerImg以及footerBtn中删除animation：

 footerImg.layer.removeAllAnimations() 

在方法的开始。

Answer 2

您应该避免使用连续animation的完成块在这种嵌套中sortinganimation。 这不仅使得它难以理解，而且难以理解和解决你所提到的问题。

有一个更好的select，称为关键帧animation，你应该考虑使用它（可用iOS 7以上）。

 animateKeyFramesWithDuration:delay:options:animation:completion 

参考文档

您的animation代码可以使用关键帧来重写（PS：我没有testing过这个，只需input你的参考）

 func animateFinished(textToDisplay: String, footerBtn: UIButton, footerImg: UIImageView) { //Should cancel any current animation footerBtn.layer.removeAllAnimations() footerImg.layer.removeAllAnimations() footerBtn.alpha = 0 footerBtn.setTitle(textToDisplay, forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Regular", size: 18) footerBtn.setTitleColor(UIColor(red: 255/255.0, green: 255/255.0, blue: 255/255.0, alpha: 1.0), forState: UIControlState.Normal) //footerBtn.backgroundColor = UIColor(red: 217/255.0, green: 217/255.0, blue: 217/255.0, alpha: 1.0) UIView.animateKeyframesWithDuration(3.0 /*Total*/, delay:0.0, options: UIViewKeyframeAnimationOptions.CalculationModeLinear, animations: { UIView.addKeyframeWithRelativeStartTime(0.0, relativeDuration:0.10, animations:{ footerImg.alpha = 0.01 //Img fades out footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 103/255.0, blue: 00/255.0, alpha: 0.6) //Bg turns to green }) UIView.addKeyframeWithRelativeStartTime(0.0, relativeDuration:0.30, animations:{ footerBtn.alpha = 1 //Text and green bg fades in footerBtn.backgroundColor = UIColor(red: 46/255.0, green: 173/255.0, blue: 11/255.0, alpha: 0.6) //BG turns greener }) UIView.addKeyframeWithRelativeStartTime(0.0, relativeDuration:0.50, animations:{ footerBtn.alpha = 0.01 //Text fades out & bg fade out }) }, completion: { finished in footerImg.alpha = 1 footerBtn.alpha = 1 footerBtn.backgroundColor = UIColor.clearColor() footerBtn.setTitleColor(UIColor(red: 55/255.0, green: 55/255.0, blue: 55/255.0, alpha: 1.0), forState: UIControlState.Normal) footerBtn.titleLabel!.font = UIFont(name: "HelveticaNeue-Light", size: 18) footerBtn.setTitle("", forState: UIControlState.Normal) //Completion blocks sets values back to norm } ) }//End of 'Finished' animation 

也请参阅这个链接，虽然它是obj c，非常丰富。 http://www.raizlabs.com/dev/2015/01/uiview-animation-sequencing-and-grouping-techniques/