用于Modal UIViewController的UIViewAnimationTransitionCurlDown或UIViewAnimationTransitionCurlUp

Question

我正在以模态方式添加UIViewController，并希望应用UIViewAnimationTransitionCurlDown转换。下面的代码不能很好地工作。它试图过渡，但很快就会震撼视野，没有任何反应。请建议可以做些什么。这是我第一次以模态方式添加UIViewController。

aboutViewController = [[AboutViewController alloc]
                       initWithNibName:@"AboutViewController" bundle:nil];
[self presentModalViewController: aboutViewController animated: YES];
UIViewAnimationTransition trans = UIViewAnimationTransitionCurlDown;
[UIView beginAnimations: nil context: nil];
[UIView setAnimationTransition: trans forView: [aboutViewController view] cache: YES];
[UIView commitAnimations];