使用 AVAudioPlayer 播放多个音频文件

Question

我在 Main StoryBoard 上创建了 3 个 UIButton。

当我按下“Button1”或“Button2”时，每个都会播放一个音频文件（“player 1”，“player 2”。），当音频播放时，UIButton 设置为selected。

我想让“Button3”连续实现多个功能。 这意味着当我按下“按钮 3”时，应该首先播放“玩家 3”，然后是“玩家 1”，然后是“玩家 2”。

但是，当我按下“Button3”时，“player 1”和“player 2”同时播放，因为前一个完成没有延迟。

我发现设置 AVAudioPlayer 的委托或使用 AVQueuePlayer 可以解决问题，但我发现很难进行更改。

    fileprivate var player1:AVAudioPlayer?
    fileprivate var player2:AVAudioPlayer?
    fileprivate var player3:AVAudioPlayer?


    @IBAction func pushButton1(sender: UIButton) {
        audioPlayer1(url: url1)
    }

    @IBAction func pushButton2(sender: UIButton) {
        audioPlayer2(url: url2)
    }

    @IBAction func pushButton3(_ sender: UIButton) {
        audioPlayer3(url: url1, url2: url2, url3: url3)
    }


    func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) {
        if (player === player1) {
            yourButton1.isSelected = false
        } else if (player === player2) {
            yourButton2.isSelected = false
        } else if (player === player3) {

            //"player 1" and "player 2" are played at same time

            yourButton3.isSelected = false
            player1!.play()
            yourButton1.isSelected = true
            player2!.play()
            yourButton2.isSelected = false
        }
    }


    func audioPlayer1(url: URL) {
        do {
            try player1 = AVAudioPlayer(contentsOf:url)
            player1!.play()
            yourButton1.isSelected = true
            player1!.delegate = self
        } catch {
            print(error)
        }
    }

    func audioPlayer2(url: URL) {
        do {
            try player2 = AVAudioPlayer(contentsOf:url)
            player2!.play()
            yourButton2.isSelected = true
            player2!.delegate = self

        } catch {
            print(error)
        }
    }

    func audioPlayer3(url: URL, url2: URL, url3: URL) {
        do {
            try player3 = AVAudioPlayer(contentsOf:url3)
            try player1 = AVAudioPlayer(contentsOf: url1)
            try player2 = AVAudioPlayer(contentsOf: url2)
            player3!.play()
            yourButton3.isSelected = true
            player3!.delegate = self
            player1!.delegate = self
        } catch {
            print(error)
        }
    }
}

更改代码

    var queue = AVQueuePlayer()
    var items = [AVPlayerItem]()


    override func viewDidLoad() {
        super.viewDidLoad()
        player1?.delegate = self
        player2?.delegate = self
        player3?.delegate = self

        let asset1 = AVPlayerItem(url: url1)
        let asset2 = AVPlayerItem(url: url2)
        let asset3 = AVPlayerItem(url: url3)
        let asset4 = AVPlayerItem(url: url4)

        items = [asset1, asset2, asset3, asset4]

        queue = AVQueuePlayer(items: items)
        for item in queue.items() {
            NotificationCenter.default.addObserver(self, selector: #selector(playerItemDidReachEnd(notification:)), name: .AVPlayerItemDidPlayToEndTime, object: item)
        }

    }
 @IBAction func pushButton3(_ sender: UIButton) {
        //audioPlayer3(url: url1, url2: url2)
        sender.isSelected = true
        queue.play()
    }
 func playerItemDidReachEnd(notification: NSNotification) {

        if notification.object as? AVPlayerItem == items[0] {
            yourButton3.isSelected = false
            yourButton1.isSelected = true
        }

        if notification.object as? AVPlayerItem == items[1] {
            yourButton1.isSelected = false
            yourButton2.isSelected = true
        }

        if notification.object as? AVPlayerItem == items[2] {
            yourButton2.isSelected = false
            yourButton4.isSelected = true
            //yourButton1.isSelected = true
        }

        if notification.object as? AVPlayerItem == items[3] {
            yourButton4.isSelected = false
            print("item 3")
        }

Answer 1

编辑：This is the method 用于 AVAudioPlayer

所以基本上：

1：只添加一个玩家，移除其余玩家。

2： Create an NSMutableArray 与您想玩的对象。

3：根据按下的按钮，您可以重新排列NSMutableArray 对象以根据需要设置正确的顺序。 （如果你想让它变得简单，只需重新创建数组）并开始播放数组中的firstObject（url），将它相应地添加到你的播放器中。

4：播放器完成播放后，您可以开始播放下一个对象，将其从NSMutableArray 添加到播放器，方法与上述相同。

遵循上述步骤将避免多个玩家同时玩，以及其他好处（例如避免同时加载多个 URL 等）

您可能需要一些变量来检查 currentPlayingObject 以确定哪个是下一个，可能是int，并检查如果它是最后播放的项目，您不会尝试从数组中加载新项目，以避免在访问不存在的 objectAtIndex 时崩溃。