从UITabBarController调用的MPMoviePlayerViewController不会在IOS5中发送通知

Question

我的应用程序在IOS4中运行良好，但在IOS5中停止显示视频。以前我使用MPMoviePlayerController，所以我切换到MPMoviePlayerViewController，现在视频在IOS5中显示正常。

但是，现在在IOS5中，当按下完成按钮时，视频停止在MPMoviePlayerViewController中播放，但MPMoviePlayerController不再调用通知。

层次结构如下：

AppDelegate - ＆gt; UITabBarController - ＆gt; UITableView - ＆gt;调用MPMoviePlayerViewController的UIViewController。在UIViewController中，代码如下：

MPMoviePlayerViewController *tmpMoviePlayer = [[MPMoviePlayerViewController alloc] initWithContentURL:movieURL];
self.moviePlayer = tmpMoviePlayer;

[self presentMoviePlayerViewControllerAnimated:self.moviePlayer];

NSNotificationCenter *notificationCenter = [ NSNotificationCenter defaultCenter ];
[notificationCenter addObserver:self  
                       selector:@selector(moviePlayerPlaybackDidFinish:)  
                           name:MPMoviePlayerWillExitFullscreenNotification  
                         object:[self.moviePlayer moviePlayer ]]; 

我还尝试了以下通知名称，但没有一个被触发：

 MPMoviePlayerPlaybackDidFinishNotification 
 MPMoviePlayerPlaybackStateDidChangeNotification
 MPMoviePlayerPlaybackDidFinishReasonUserInfoKey
 MPMoviePlayerNowPlayingMovieDidChangeNotification
 MPMoviePlayerWillExitFullscreenNotification
 MPMoviePlayerDidExitFullscreenNotification

我看过一个SO posting，其中从UITabBarController中调用了MPMoviePlayerViewController，并且没有正确选择调用presentMoviePlayerViewControllerAnimated的视图，但是我无法让任何其他视图用于调用presentMoviePlayerViewControllerAnimated。

当按下MPMoviePlayerViewController的Done按钮时，为什么不再调用通知的任何想法？

Answer 1

我确实解决了这个问题，但我不记得实际修复了什么。但我可以展示现在有效的代码：

[ notificationCenter addObserver: self 
                            selector:@selector(moviePlayerPlaybackDidFinish:) 
                            name: MPMoviePlayerPlaybackDidFinishNotification 
                            object: moviePlayer ];


self.moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:movieURL];
self.moviePlayer.shouldAutoplay = NO;  
[self.moviePlayer setControlStyle:MPMovieControlStyleFullscreen];
[[self view] addSubview:[self.moviePlayer view]];   
[self.moviePlayer setFullscreen:YES animated:YES];
[self.moviePlayer play];