MPRemoteCommandCenter 4中的错误

Question

我正在尝试设置我的应用程序使用MPRemoteCommandCenter。我从文档编程指南中获得了这个示例。我导入了AVFoundation，甚至尝试导入AVKIT，我得到了未解析标识符'MPRemoteCommandCenter'的错误用法。当我创建MPRemoteCommandCenter.shared()的实例时。任何帮助都将不胜感激。

func setupRemoteTransportControls() {

    // Get the shared MPRemoteCommandCenter
    let commandCenter = MPRemoteCommandCenter.shared()   Error //**Use of unresolved identifier 'MPRemoteCommandCenter'**

    // Add handler for Play Command
    commandCenter.playCommand.addTarget { [unowned self] event in
        if self.audioPlayer.rate == 0.0 {
            self.audioPlayer.play()
            return .success
        }
        return .commandFailed
    }

    // Add handler for Pause Command
    commandCenter.pauseCommand.addTarget { [unowned self] event in
        if self.audioPlayer.rate == 1.0 {
            self.audioPlayer.pause()
            return .success
        }
        return .commandFailed
    }
}

Answer 1

你需要import MediaPlayer