IOS setAnimationTransition设置过度效果

setAnimationTransition(_transition：UIView-AnimationTransition,
 for view：UIView, cache：Bool)
 //第一个参数：
 flipFromLeft 从左边滑入
 flipFromRight
 curlUp    从底部
 curlDown 从顶部
 none
//实现翻页的效果
 23 func playAnimation()
 24 {
 25 UIView.beginAnimations(nil, context：nil)
 26 UIView.setAnimationCurve(.easeOut)
 27 UIView.setAnimationDuration(5)
 28 UIView.setAnimationBeginsFromCurrentState(true)
 29
 30 let view = self.view.viewWithTag(1)
 31 UIView.setAnimationTransition(.curlUp, for：view！,
 cache：true)
 32
 33 UIView.setAnimationDelegate(self)
 34
 UIView.setAnimationDidStopSelector(#selector(ViewController.animationStop))
 35 UIView.commitAnimations()
 36 }