ios - `audioPlayerDidFinishPlaying` 未被调用

Question

这个问题已经有答案了:

AVAudioPlayer.play() does not play sound (1 个回答)

已关闭 3 年前。

遇到问题 audioPlayerDidFinishPlaying没有被调用...

我查看了其他一些 SO 线程:

Swift: AudioPlayerDidFinished will not be called

AVAudioPlayerDelegate doesn't call the method

...但仍然遇到同样的问题。

我已经设置了我的ViewController符合AVAudioPlayerDelegate :

class ViewController: UIViewController, AVAudioPlayerDelegate {
var audioEngine = AVAudioEngine()
...
}

并在此处创建播放器；创建播放器本身后立即设置委托(delegate):

func startAudioEngine(audioFileURL: URL) {

    var player: AVAudioPlayer?

    do {
        try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default)
        try AVAudioSession.sharedInstance().setActive(true)

        player = try AVAudioPlayer(contentsOf: audioFileURL, fileTypeHint: AVFileType.mp3.rawValue)

        guard let player = player else { return }
        player.delegate = self

        player.prepareToPlay()
        player.play()

    } catch let error {
        print(error.localizedDescription)
    }
}

Answer 1

你的问题是双重的:

1. var player: AVAudioPlayer? 被声明为 func startAudioEngine() 的本地函数，因此一旦该函数存在，您就会失去对 player 的引用>.
2. 您正在选择性绑定(bind)的播放器上设置委托(delegate)

更改为此(或类似的内容):

class ViewController: UIViewController, AVAudioPlayerDelegate {
  var audioEngine = AVAudioEngine()
  var player: AVAudioPlayer?
}

然后在分配 player 后，声明您的委托(delegate) self.player?.delegate = self。确保包含 self.，以便在类属性上设置委托(delegate)，而不是在可选绑定(bind)上设置委托(delegate)；