MPNowPlayingInfoCenter 未显示，但后台播放正常

Question

我制作了 MPNowPlayingInfoCenter，但它不起作用。后台播放正常，但 MPNowPlayingCenter 没有出现。我就是这样做的。

import UIKit
import AVFoundation
import MediaPlayer

class AudioPlayViewController: UIViewController, AVAudioPlayerDelegate {
  var player: AVAudioPlayer!
  var updater: CADisplayLink! = nil

  @IBOutlet weak var playButton: UIButton!
  var url_2 = URL(string: "")
  var selectedFileName:String = ""

  override func viewDidLoad() {
    super.viewDidLoad()
    let path = selectedFileName
    let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
    let url = documentsURL.appendingPathComponent(path)
    url_2 = url

    do {
      player = try AVAudioPlayer(contentsOf: url)
      updater = CADisplayLink(target: self, selector: #selector(self.trackAudio))
      updater.preferredFramesPerSecond = 1
      updater.add(to: RunLoop.current, forMode: RunLoop.Mode.common)
      player.prepareToPlay()
      player.delegate = self
    catch {
      print(error)
    }
    let session = AVAudioSession.sharedInstance()
    do{
      try session.setCategory(AVAudioSession.Category.playback)
    }
    catch{
    }
  }

  func play(){
    player.play()
    MPNowPlayingInfoCenter.default().nowPlayingInfo = [
      MPMediaItemPropertyTitle: selectedFileName,
      MPMediaItemPropertyArtist: "Ariana",
      MPMediaItemPropertyLyrics: "test"
      ]
  }
}

我在 Targets > Signing&Capabilities 中设置了背景模式 > 音频、Airplay 和画中画。

Answer 1

我通过添加

解决了它

func setupNowPlayingInfoCenter(){
    UIApplication.shared.beginReceivingRemoteControlEvents()
    MPRemoteCommandCenter.shared().playCommand.addTarget {event in
      self.play()
      return .success
    }
    MPRemoteCommandCenter.shared().pauseCommand.addTarget {event in
      self.pause()
      return .success
    }
    MPRemoteCommandCenter.shared().nextTrackCommand.addTarget {event in
      self.goForward()
      return .success
    }
    MPRemoteCommandCenter.shared().previousTrackCommand.addTarget {event in
      self.goBackward()
      return .success
    }
  }

MPNowPlayingInfoCenter 未显示，但后台播放正常

MPNowPlayingInfoCenter is not showing but background playing does work

ios

avaudioplayer