title: send URL of assets-library to MPMoviePlayerController
body: <p>I want to play movie from assets-library. I get a ALAsset from camera roll, then send its URL to MPMoviePlayerController:</p>
  
  <pre><code>xxxViewController *SelectVC = [[xxxViewController alloc] initWithContentURL: [[mediumAsset defaultRepresentation]url]];
  
  - (id)initWithContentURL:(NSURL *)contentURL
  {
      self = [super initWithNibName:nil bundle:nil];
  
      if (self)
      {
          moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:contentURL];
  
          [moviePlayer setShouldAutoplay:NO];
          [moviePlayer setControlStyle:MPMovieControlStyleFullscreen];
          [moviePlayer prepareToPlay];
  
          [[NSNotificationCenter defaultCenter] addObserver:self 
                                                   selector:@selector(moviePlayerLoadStateChanged:) 
                                                       name:MPMoviePlayerLoadStateDidChangeNotification 
                                                     object:nil];
  
      }
  
      return self;
  }
  </code></pre>
  
  <p>The error message as:</p>
  
  <pre><code>[MPAVController] Autoplay: Skipping autoplay, disabled (for current item: 0, on player: 1)
  2012-07-23 19:11:54.194 [5466:907] url assets-library://asset/asset.mov?id=DA201372-BC11-4C0A-B134-B7E89FBC7DAF&amp;ext=mov
  2012-07-23 19:11:54.286 [5466:907] [MPAVController] Autoplay: Enabling autoplay
  2012-07-23 19:11:54.289 [5466:907] Error (null) setting playback mode to 'AVAudioSessionModeDefault'
  2012-07-23 19:11:54.313 [5466:907] [MPAVController] Autoplay: Skipping autoplay, disabled (for current item: 0, on player: 1)
  2012-07-23 19:11:54.340 [5466:907] [MPQueuePlayer] Inserting item &lt;AVPlayerItem: 0x209eaae0, asset = &lt;AVURLAsset: 0x209e8f20, URL = assets-library://asset/asset.mov?id=DA201372-BC11-4C0A-B134-B7E89FBC7DAF&amp;ext=mov&gt;&gt; into player &lt;AVQueuePlayer: 0x20a65f90&gt;
  2012-07-23 19:11:54.408 [5466:907] [MPQueuePlayer] Items after insertion: (
      "&lt;AVPlayerItem: 0x209eaae0, asset = &lt;AVURLAsset: 0x209e8f20, URL = assets-library://asset/asset.mov?id=DA201372-BC11-4C0A-B134-B7E89FBC7DAF&amp;ext=mov&gt;&gt;"
  )
  2012-07-23 19:11:54.930 [5466:907] [MPAVController] Autoplay: Skipping autoplay, disabled (for current item: 0, on player: 1)
  2012-07-23 19:11:54.956 [5466:907] [MPAVController] Autoplay: _streamLikelyToKeepUp: 0 -&gt; 1
  </code></pre>