详解IOS图层转场动画

 控制器直接切换动画

 UIApplication *app=[UIApplication sharedApplication];
  AppDelegate *dd=app.delegate;
  
    MyViewController *my=[[MyViewController alloc] init];
  //切换根控制器，其实把视图控制器的view在window上切换。所以在转场动画要作用在window上
  dd.window.rootViewController=my;
  CATransition *trans=[CATransition animation];
  
  trans.type=@"pageCurl";
  trans.subtype=@"fromTop";
  
  [dd.window.layer addAnimation:trans forKey:nil];
  
  [my release];