swift - swift 4 中的 MPRemoteCommandCenter 错误

Question

我正在尝试设置我的应用程序以使用 MPRemoteCommandCenter。我从文档编程指南中得到了这个例子。我导入了 AVFoundation，甚至尝试导入 AVKIT，我收到错误消息Use of unresolved identifier 'MPRemoteCommandCenter'。当我创建 MPRemoteCommandCenter.shared() 的实例时。任何帮助将不胜感激。

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

您需要导入MediaPlayer