在IOS开发中，我们model另外一个控制器的时候，一般都使用默认的转场动画。
其实我们可以自定义一些转场动画。达到不同的转场效果。
步骤如下：(photoBrowser是目标控制器)
1.在源控制器中，设置目标控制器的转场代理为 self
1 //设置Model转场代理 2 photoBrowser.transitioningDelegate = self
2.同时设置目标控制器的model类型
1 //设置Model类型 2 photoBrowser.modalPresentationStyle=UIModalPresentationStyle.Custom
3.定义一个变量记录转场还是退场 （true为转场，false为退场
1 var isPersent = false
4.在源控制器中设置跳转，目标控制器中设置关闭（动画要选择true）
1 presentViewController(photoBrowser, animated: true) { () -> Void in }
2 dismissViewControllerAnimated(true){SVProgressHUD.dismiss()}
5.源控制器遵守两个代理
UIViewControllerTransitioningDelegate，
UIViewControllerAnimatedTransitioning
6.源控制器实现2个代理方法
1 func animationControllerForPresentedController(presented: UIViewController, presentingController presenting: UIViewController, sourceController source: UIViewController) -> UIViewControllerAnimatedTransitioning?{
2 //转场
3 isPersent = true
4 //源控制器自己负责转场
5 return self
6 }
7
8 func animationControllerForDismissedController(dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning?{
9
10 //退场
11 isPersent = false
12 //源控制器自己负责转场
13 return self
14 }
7.源控制器再实现2个代理方法
1 //转场时间
2 func transitionDuration(transitionContext: UIViewControllerContextTransitioning) -> NSTimeInterval
3
4 //转场上下文，负责转场动画的具体内容
5 func animateTransition(transitionContext: UIViewControllerContextTransitioning){
6 //转场动画
7 if isPersent{
8 if let toView = transitionContext.viewForKey(UITransitionContextToViewKey){
9 //将傀儡视图（用于动画时展现的画面）加入containerView()
10 transitionContext.containerView().addSubview(self.persentedDummyView!)
11 toView.frame = CGRectZero
12 self.persentedDummyView?.frame = CGRectZero
13
14 UIView.animateWithDuration(2.0, animations: { () -> Void in
15 self.persentedDummyView?.frame = transitionContext.containerView().frame
16 toView.frame = UIScreen.mainScreen().bounds
17 }, completion: { (_) -> Void in
18 //移除傀儡视图
19 self.persentedDummyView?.removeFromSuperview()
20 //加入要正常显示的视图
21 transitionContext.containerView().addSubview(toView)
22 //结束
23 transitionContext.completeTransition(true)
24 })
25 }
26 }
27 //退场动画
28 if !isPersent{
29 if let fromView = transitionContext.viewForKey(UITransitionContextFromViewKey){
30
31 //隐藏目标控制器
32 let fromVC = transitionContext.viewControllerForKey(UITransitionContextFromViewControllerKey) as! HJCPhotoBrowserViewController
33 fromVC.view.hidden = true
34 //获得fromVC的快照
35 let dummy = fromVC.collectionView.visibleCells().last!.snapshotViewAfterScreenUpdates(false)
36 //将傀儡视图放入containerView
37 transitionContext.containerView().addSubview(dummy)
38 //执行动画
39 UIView.animateWithDuration(2.0, animations: { () -> Void in
40 dummy.frame = CGRectZero
41 }, completion: { (_) -> Void in
42 //移除傀儡视图
43 dummy.removeFromSuperview()
44 //结束
45 transitionContext.completeTransition(true)
46 })
47 }
48 }
49 }
50
51
52 }