播放/暫停按鈕不會在鎖屏中更新總是會在 Swift4 ios 中顯示暫停按鈕

Question

我有一個可以從 iOS 命令中心和鎖定屏幕播放的音頻播放器。 當我在我的應用程序中切換播放/暫停按鈕時，它應該通過更新 nowPlayingInfo (MPNowPlayingInfoCenter) 來更新命令中心 (MPRemoteCommandCenter) 中的播放/暫停按鈕。 但它沒有更新。

但是當我嘗試從鎖屏播放/暫停在我的應用程序切換按鈕中控制它的更新時，這工作正常。但類似地，當我從我的應用程序播放/暫停按鈕內部進行控制時。 它沒有更新鎖屏中的播放/暫停按鈕。總是顯示暫停按鈕。

我設置 Playbackrate 1.0 播放和 0.0 暫停。但它仍然沒有更新..

有些人可以給我任何建議或以下代碼中缺少的任何內容。

   func setupLockScreenDisplay() {
        var nowPlayingInfo = [String: Any]()
        nowPlayingInfo[MPMediaItemPropertyTitle] = self.currentSongName
        nowPlayingInfo[MPMediaItemPropertyPlaybackDuration] = self.currentAlbum == nil ? self.totalDurationTime : playerItem.asset.duration.seconds
        nowPlayingInfo[MPNowPlayingInfoPropertyPlaybackRate] = isPlaying ? 1.0 : 0.0
        nowPlayingInfo[MPNowPlayingInfoPropertyMediaType] = NSNumber(value: MPNowPlayingInfoMediaType.audio.rawValue)
        nowPlayingInfo[MPNowPlayingInfoPropertyElapsedPlaybackTime] = self.currentAlbum == nil ? self.storyPlayer.currentTime : CMTimeGetSeconds(player.currentTime())
        // Set the metadata
        MPNowPlayingInfoCenter.default().nowPlayingInfo = nowPlayingInfo
        MPNowPlayingInfoCenter.default().playbackState = .playing
    }

下面的遠程命令代碼工作正常..我可以從鎖屏控制

func setupRemoteCommandCenter() {
        let commandCenter = MPRemoteCommandCenter.shared()
        commandCenter.playCommand.isEnabled = true
        commandCenter.playCommand.addTarget { event in
            self.play()
            return .success
        }
        commandCenter.pauseCommand.isEnabled = true
        commandCenter.pauseCommand.addTarget { event in
            self.pause()
            return .success
        }
        commandCenter.nextTrackCommand.isEnabled = true
        commandCenter.nextTrackCommand.addTarget { event in
            self.nextPlay()
            return .success
        }
        commandCenter.previousTrackCommand.isEnabled = true
        commandCenter.previousTrackCommand.addTarget { event in
            self.lastPlay()
            return .success
        }
        commandCenter.togglePlayPauseCommand.isEnabled = true
    }

這里是內部播放按鈕的代碼

func play() {
        if self.currentAlbum == nil {
            self.storyPlayer.play()
        } else {
            self.player.play()
        }
        self.isPlaying = true
        NotificationCenter.default.post(name: Notification.Name(rawValue: kPlayerManagerChangePlayingStateRsp), object: nil)
        setupLockScreenDisplay()
        setupRemoteCommandCenter()
        MPNowPlayingInfoCenter.default().nowPlayingInfo![MPNowPlayingInfoPropertyPlaybackRate] = 1
        MPNowPlayingInfoCenter.default().nowPlayingInfo![MPNowPlayingInfoPropertyElapsedPlaybackTime] = CMTimeGetSeconds(player.currentTime())
    }

暫停按鈕內的代碼

func pause() {
        if self.currentAlbum == nil {
            self.storyPlayer.pause()
        } else {
            self.player.pause()
        }
        self.isPlaying = false
        NotificationCenter.default.post(name: Notification.Name(rawValue: kPlayerManagerChangePlayingStateRsp), object: nil)
        setupLockScreenDisplay()
        setupRemoteCommandCenter()
        MPNowPlayingInfoCenter.default().nowPlayingInfo![MPNowPlayingInfoPropertyPlaybackRate] = 0
        MPNowPlayingInfoCenter.default().nowPlayingInfo![MPNowPlayingInfoPropertyElapsedPlaybackTime] = CMTimeGetSeconds(player.currentTime())
    }

Answer 1

在您的視圖中添加此代碼確實加載了 func 或應用程序委托

do {
     try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default, options: [.mixWithOthers, .allowAirPlay])
     print("Playback OK")
     try AVAudioSession.sharedInstance().setActive(true)
     print("Session is Active")
   } 
   catch {
     print(error)
   }

以及您的后台模式功能。