iOS 启用 AVPlayer 以继续在后台播放

Question

I'm working on an app with a built in video player that plays mp4 videos from disk and I'm trying to make it continue playing the audio (of the video) when app goes into background .

I've read up on many other stack overflow questions but none of the answers worked for my case.

I have added:

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
  do {
    try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)
      print("AVAudioSession Category Playback OK")

    do {
      try AVAudioSession.sharedInstance().setActive(true)
      print("AVAudioSession is Active")
    } catch let error as NSError {
      print(error.localizedDescription)
    }
  } catch let error as NSError {
      print(error.localizedDescription)
  }
}

Besides, I also have the required background mode key App plays audio or streams audio/video using AirPlay in the app's Info.plist file. However, the AVPlayer stops when the app goes into background.

Anyone knows what might be wrong with the app?

Thanks :)

Edit: Note: I'm using AVPlayerLayer together with AVPlayer . Maybe this is the problem?

Answer 1

Yes AVPlayerLayer might be creating issue. You need to remove it from AVPlayer object. Set to nil before application go to background.

Two ways to resolve according to Apple Document,

1. Disable the video tracks in the player item (file-based content only).

2. Remove the AVPlayerLayer from its associated AVPlayer (set the AVPlayerLayer player property to nil).

Refer this link for more info.

Answer 2

First you must have enabled "Background Audio" in Capability. Follow bellow link to do so.

[See image to Enable Background Audio]

When your app moves to background, assign your player to nil.

// If presenting video with AVPlayerViewController
    playerViewController.player = nil

// If presenting video with AVPlayerLayer
    playerLayer.player = nil

When your app moves to foreground again, do as given bellow.

// If presenting video with AVPlayerViewController
playerViewController.player = player

// If presenting video with AVPlayerLayer
playerLayer.player = player