播放下一首歌AVAudioPlayer

Question

我有一個包含歌曲列表的tableviewcontroller，只要用戶點擊一首歌曲，它就會打開另一個視圖控制器並播放它。每當用戶按下下一個按鈕或前一個按鈕時，我都需要幫助，以便播放上一首或下一首歌曲。這裏是我的tableviewcontroller：

import UIKit 

class LibraryTableViewController: UITableViewController { 

    var titleText = ["Heroes", "Skyline", "In The Woods"] 
    var authorText = ["Kedam", "Kovan & Electro Light", "Max Pros"] 

    @IBOutlet var songList: UITableView! 


    override func viewDidLoad() { 
     super.viewDidLoad() 



    } 


    // MARK: - Table view data source 

    override func numberOfSections(in tableView: UITableView) -> Int { 
     // #warning Incomplete implementation, return the number of sections 
     return 1 
    } 

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int { 
     // #warning Incomplete implementation, return the number of rows 
     return titleText.count 
    } 

    //tableview delegate 

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell { 
     var cell : LibrarySongTableViewCell! = tableView.dequeueReusableCell(withIdentifier: "Library Cell") as! LibrarySongTableViewCell 
     if(cell == nil) 
     { 
      cell = Bundle.main.loadNibNamed("Library Cell", owner: self, options: nil)?[0] as! LibrarySongTableViewCell; 
     } 
     let titleTitle = titleText[indexPath.row] as String //NOT NSString 
     let authorTitle = authorText[indexPath.row] as String 
     cell.titleLabel.text=titleTitle 
     cell.authorLabel.text=authorTitle 
     cell.imageView?.image = UIImage(named: titleTitle) 
     cell.imageView?.layer.cornerRadius = 5 
     return cell as LibrarySongTableViewCell 

    } 


    override func prepare(for segue: UIStoryboardSegue, sender: Any?) 
    { 
     if segue.identifier == "toLibraryDetail" 
     { 
      let detailViewController = ((segue.destination) as! LibraryDetailViewController) 
      let indexPath = self.songList!.indexPathForSelectedRow! 
      let topicLabelText = titleText[indexPath.row] 
      let detailLabelText = authorText[indexPath.row] 
      detailViewController.titleLabelText = topicLabelText 
      detailViewController.authorLabelText = detailLabelText 



     } 

    } 

} 

這裏是該小區去播放該歌曲的視圖控制器：

import UIKit 
    import AVFoundation 
    import MediaPlayer 

    // audioPlayer Outlet 
    var libraryPlayer = AVAudioPlayer() 

    class LibraryDetailViewController: UITableViewController, AVAudioPlayerDelegate { 

     // Title and Author 
     var titleLabelText: String! 
     var authorLabelText: String! 
     @IBOutlet weak var albumArt: UIImageView! 
     @IBOutlet weak var titleText: UILabel! 
     // Image Outlets 
     @IBOutlet weak var authorText: UILabel! 
     @IBOutlet weak var blurredAlbumArt: UIImageView! 
     // Toolbar Outlets 
     @IBOutlet weak var toolbar: UIToolbar! 
     var playButton: UIBarButtonItem! 
     var pauseButton: UIBarButtonItem! 
     var flexibleSpace: UIBarButtonItem! 
     var nextButton: UIBarButtonItem! 
     var previousButton: UIBarButtonItem! 

     override func viewDidLoad() { 
      super.viewDidLoad() 
      // Customize Album Art 
      albumArt.image = UIImage(named: titleLabelText) 
      blurredAlbumArt.image = UIImage(named: titleLabelText) 
      albumArt.layer.cornerRadius = 10 
      // Set label text 
      titleText.text = titleLabelText 
      authorText.text = authorLabelText 


      // Create the audioPlayer 
      do { 

       libraryPlayer = try AVAudioPlayer(contentsOf: URL.init(fileURLWithPath: Bundle.main.path(forResource: titleLabelText, ofType: "mp3")!)) 
       libraryPlayer.delegate = self 


       libraryPlayer.prepareToPlay() 

       var audioSession = AVAudioSession.sharedInstance() 



       do { 

        try audioSession.setCategory(AVAudioSessionCategoryPlayback) 

       } 

      } 

      catch { 

       print(error) 

      } 

      // Create ToolBar Buttons 
      playButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.play, target: self, action: "playButtonTapped") 
      pauseButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.pause, target: self, action: "pauseButtonTapped") 
      flexibleSpace = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.flexibleSpace, target: self, action: nil) 
      previousButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.rewind, target: self, action: "previousButtonTapped") 
      nextButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.fastForward, target: self, action: "nextButtonTapped") 

      // Customize ToolBar Buttons 
      previousButton.tintColor = UIColor.lightGray 
      nextButton.tintColor = UIColor.lightGray 

      toolbar.items = [flexibleSpace, previousButton, flexibleSpace, pauseButton, flexibleSpace, nextButton, flexibleSpace] 


      // Set the delegate 

      // Play 
      libraryPlayer.play() 



      // Do any additional setup after loading the view. 
     } 

     // Play 
     func playButtonTapped() { 
      toolbar.items = [flexibleSpace, previousButton, flexibleSpace, pauseButton, flexibleSpace, nextButton, flexibleSpace]; 
      libraryPlayer.play() 
     } 

     // Pause 
     func pauseButtonTapped() { 
      toolbar.items = [flexibleSpace, previousButton, flexibleSpace, playButton, flexibleSpace, nextButton, flexibleSpace]; 
      libraryPlayer.pause() 
     } 

     // Previous 
     func previousButtonTapped() { 
// NEED HELP HERE 
     } 

     // Next 
     func nextButtonTapped() { 
// NEED HELP HERE 
     } 

     override func viewDidDisappear(_ animated: Bool) { 
      libraryPlayer.pause() 
     } 

     override func viewDidAppear(_ animated: Bool) { 
      libraryPlayer.play() 
     } 

     override func didReceiveMemoryWarning() { 
      super.didReceiveMemoryWarning() 
      // Dispose of any resources that can be recreated. 
     } 


     @IBAction func dismiss(_ sender: Any) { 
      dismiss(animated: true, completion: nil) 
     } 
    } 

感謝這麼多的幫助！我使用的是斯威夫特3和Xcode的8

Answer 1

你可以通過歌曲列表排列在Librarydetailviewcontroller和使用audioPlayerDidFinishPlaying委託下一首歌曲......否則，你可以在「nextButtonTapped」

var currentSoundsIndex: Int = 0 

override func viewDidLoad() { 
super.viewDidLoad() 
currentSoundsIndex = 0 
playCurrentSong() 
} 

func playCurrentSong() { 
var error: Error? 
mediaPlayer = try? AVAudioPlayer(contentsOfURL: URL(fileURLWithPath: Bundle.main.path(forResource: soundList[currentSoundsIndex], ofType: nil))) 
if error != nil { 
    print("\(error)") 
    //Also possibly increment sound index and move on to next song 
} 
else { 
    lblCurrentSongName.text = soundList[currentSoundsIndex] 
    mediaPlayer.delegate = self 
    mediaPlayer.prepareToPlay() 
    //This is not always needed, but good to include 
    mediaPlayer.play() 
    } 
} 


func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) { 
//Increment index but don't go out of bounds 
currentSoundsIndex = currentSoundsIndex += 1 % soundList.count 
playCurrentSong() 
} 

使用 playCurrentSong FUNC