锁屏 iPhone 上的音乐控制

Posted 2023-04-15

【中文标题】锁屏 iPhone 上的音乐控制

【英文标题】：Music control at lock screen iPhone

【发布时间】：2017-03-17 06:06:40

【问题描述】：

我正在开发音乐应用程序，但对于锁屏控制，我无法指定持续时间和经过的时间

这是我的代码

let commandCenter = MPRemoteCommandCenter.shared()

        commandCenter.previousTrackCommand.isEnabled = true;
        commandCenter.previousTrackCommand.addTarget(self, action:#selector(home_ViewController.btn_rewind(_:)))

        commandCenter.nextTrackCommand.isEnabled = true
        commandCenter.nextTrackCommand.addTarget(self, action:#selector(home_ViewController.btn_fast(_:)))

        commandCenter.playCommand.isEnabled = true
        commandCenter.playCommand.addTarget(self, action:#selector(home_ViewController.play_player))

        commandCenter.pauseCommand.isEnabled = true
        commandCenter.pauseCommand.addTarget(self, action:#selector(home_ViewController.pause_player))

        commandCenter.togglePlayPauseCommand.isEnabled = true
        commandCenter.togglePlayPauseCommand.addTarget(self, action:#selector(home_ViewController.togglePlay_Pause))

        commandCenter.skipBackwardCommand.isEnabled = false
        commandCenter.skipForwardCommand.isEnabled = false

        if #available(ios 9.1, *) 
            commandCenter.changePlaybackPositionCommand.isEnabled = true
         else 
            // Fallback on earlier versions
            return
        

和媒体信息

func setLockInfo()
    
        let url = URL(string: song_UrlString)
        let data = try? Data(contentsOf: url!)
        let art = MPMediaItemArtwork.init(image: UIImage(data: data!)!)



        let songInfo :[String : Any] = [MPMediaItemPropertyTitle :st_title,MPMediaItemPropertyArtwork : art]

        MPNowPlayingInfoCenter.default().nowPlayingInfo = songInfo


    

我正在获取标题和图片，但锁屏不显示时间

我正在使用 SWIFT 3 编码

【参考方案1】：

它没有显示时间，因为你没有告诉它显示时间。

要显示播放时间，您的 nowPlayingInfo 字典需要包含键的值：

MPNowPlayingInfoPropertyElapsedPlaybackTime，所以它知道你开始播放的当前时间， MPMediaItemPropertyPlaybackDuration，所以它知道当前时间是相对于条中的什么，并且 MPNowPlayingInfoPropertyPlaybackRate，所以它可以自动更新播放时间UI，无需您定期设置当前时间。

如果您希望播放时间栏具有交互性（即，允许跳转到其他时间而不是仅显示当前时间，请在远程指挥中心注册changePlaybackPositionCommand。

【讨论】：

让 songInfo :[String : Any] = [MPMediaItemPropertyTitle :st_title,MPMediaItemPropertyArtwork : art,MPNowPlayingInfoPropertyElapsedPlaybackTime : NSNumber.init(value: (player.currentTime()).value),MPMediaItemPropertyPlaybackDuration : NSNumber.init (value: ((player.currentItem?.duration)?.value)!),MPNowPlayingInfoPropertyPlaybackRate :NSNumber.init(value: 1)] 我已经改到上面了，但是还没来

能否举个例子

【参考方案2】：

Swift 3 示例，所有命令都在工作，包括 changePlaybackPositionCommand：

func remotePlayerInit() 
    UIApplication.shared.beginReceivingRemoteControlEvents()
    let commandCenter = MPRemoteCommandCenter.shared()

    commandCenter.pauseCommand.addTarget(self, action: #selector(self.pauseSongTouch(_:)))
    commandCenter.playCommand.addTarget(self, action: #selector(self.playSongTouch(_:)))
    commandCenter.nextTrackCommand.addTarget(self, action: #selector(self.nextSongTouch(_:)))
    commandCenter.previousTrackCommand.addTarget(self, action: #selector(self.previousSongTouch(_:)))
    commandCenter.changePlaybackPositionCommand.addTarget(self, action: #selector(self.changedThumbSlider(_:)))

    setLockInfo()


func changedThumbSlider(_ event: MPChangePlaybackPositionCommandEvent) -> MPRemoteCommandHandlerStatus 
    audioPlayer.currentTime = event.positionTime
    setLockInfo()
    return .success


func setLockInfo()

    let image = PlayerVC.songs[PlayerVC.currentSelection].image
    let artwork = MPMediaItemArtwork.init(boundsSize: image.size, requestHandler:  (size) -> UIImage in
        return image
    )

    let songInfo: [String: Any] = [MPMediaItemPropertyTitle:  PlayerVC.songs[PlayerVC.currentSelection].name, 
                                   MPMediaItemPropertyArtwork: artwork, 
                                   MPNowPlayingInfoPropertyElapsedPlaybackTime: TimeInterval(audioPlayer.currentTime),
                                   MPNowPlayingInfoPropertyPlaybackRate: 1,
                                   MPMediaItemPropertyPlaybackDuration: audioPlayer.duration,
                                   MPMediaItemPropertyArtist: "Artist"]

    MPNowPlayingInfoCenter.default().nowPlayingInfo = songInfo