AVPlayerLayer停止播放时，进入后台模式

Question

我设置AVPlayerLayer有：

 audioPlayer = [[AVPlayer alloc]initWithURL:[NSURL fileURLWithPath:fileName]]; 
     avPlayerLayer = [AVPlayerLayer playerLayerWithPlayer:audioPlayer]; 
     [avPlayerLayer setFrame:self.view.bounds]; 
     [[self.view layer] addSublayer:avPlayerLayer]; 
     [audioPlayer play]; 

在AppDelegete我补充一下：

[[AVAudioSession sharedInstance] setDelegate:self];  
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil]; 
[[AVAudioSession sharedInstance] setActive: YES error: nil]; 

现在UIViewController类我补充一下：

-(void)viewDidAppear:(BOOL)animated{ 
    [super viewDidAppear:animated]; 
    [[UIApplication sharedApplication] beginReceivingRemoteControlEvents]; 
    [self becomeFirstResponder]; 
} 

- (BOOL)canBecomeFirstResponder { 
    return YES; 
} 

- (void)remoteControlReceivedWithEvent:(UIEvent *)event { 
    switch (event.subtype) { 
     case UIEventSubtypeRemoteControlTogglePlayPause: 
      if (audioPlayer.rate == 0.0) { 
       [avPlayerLayer.player play]; 
      } else { 
       [avPlayerLayer.player pause]; 
      } 
      NSLog(@"4"); 
      break; 
     case UIEventSubtypeRemoteControlPlay: 
      [avPlayerLayer.player play]; 
      break; 
     case UIEventSubtypeRemoteControlPause: 
      [avPlayerLayer.player pause]; 
      NSLog(@"3"); 
      break; 
     case UIEventSubtypeRemoteControlNextTrack: 
      [self didPressNextSong:nil]; 
      NSLog(@"2"); 
      break; 
     case UIEventSubtypeRemoteControlPreviousTrack: 
      [self didPressLastSong:nil]; 
      NSLog(@"1"); 
      break; 
     default: 
      break; 
    } 
} 

现在问题是当我移动到背景模式时，歌曲停止播放，但是当我按遥控器上的播放按钮时rol（当我按下双击主页按钮时弹出的菜单）歌曲继续播放它停止播放的位置。

任何想法，为什么我有这个问题？

Answer 1

把这个解决方案：

How do I get my AVPlayer to play while app is in background?

的关键是在信息plist中UIBackgroundModes。