在范围内找不到 MPRemoteCommandCenter

Question

我创建了一个音乐应用程序，现在我想添加一个功能来从锁定屏幕和控制中心控制音乐，但我收到错误消息，MPRemoteCommandCenter 不在范围内。

这是我的代码的样子。

我正在 XCode 12 中开发，但适用于 iOS 12.4。

import UIKit
import AVKit

class SongViewController: UIViewController {
    
    
   
    
override func viewDidLoad() {
        super.viewDidLoad()
        
        
        let swipeRight = UISwipeGestureRecognizer(target: self, action: #selector(respondToSwipeGesture))
        swipeRight.direction = .right
        self.view.addGestureRecognizer(swipeRight)
        
        let swipeLeft = UISwipeGestureRecognizer(target: self, action: #selector(respondToSwipeGesture))
        swipeLeft.direction = .left
        self.view.addGestureRecognizer(swipeLeft)
        
        setupRemoteTransportControls()
        setupNowPlaying()
        
        
    }
    
    func setupRemoteTransportControls() {
        
        let commandCenter = MPRemoteCommandCenter.shared()

       
        commandCenter.playCommand.addTarget { [unowned self] event in
            print("Play command - is playing: \(self.player.isPlaying)")
            if !self.player.isPlaying {
                self.play()
                return .success
            }
            return .commandFailed
        }

        // Add handler for Pause Command
        commandCenter.pauseCommand.addTarget { [unowned self] event in
            print("Pause command - is playing: \(self.player.isPlaying)")
            if self.player.isPlaying {
                self.pause()
                return .success
            }
            return .commandFailed
        }
    }

Answer 1

您需要导入MediaPlayer 框架

import UIKit
import AVKit
import MediaPlayer

...