ios - 尝试按一个按钮然后按顺序或随机播放音频

Question

我试图按下一个按钮，音频文件一个接一个地播放。

下面是我的代码。我按下播放按钮，两种声音同时播放。我试图按下播放按钮，声音开始和停止，然后另一个声音文件开始和停止。一键按下2个声音文件是我的目标。谢谢

我正在循环尝试此操作，但它不起作用。

import UIKit
import AVFoundation

class ViewController: UIViewController {

    @IBOutlet weak var sliderValue: UISlider!

    var player:AVAudioPlayer = AVAudioPlayer()
    var player1:AVAudioPlayer = AVAudioPlayer()

    @IBAction func play(_ sender: AnyObject) {
           player.play()
           player1.play()
    }

    @IBAction func pause(_ sender: AnyObject) {
        player.pause()
    }
    @IBAction func stop(_ sender: AnyObject) {
        player.stop()
        player.currentTime = 0 
    }
    @IBAction func sliderChanged(_ sender: AnyObject) {
        player.volume = sliderValue.value 
    }
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        let audioPath =  Bundle.main.path(forResource: "sound1", ofType: "mp3")!
        let audioPath1 =  Bundle.main.path(forResource: "sound2", ofType: "mp3")!
        do {   
            try player = AVAudioPlayer(contentsOf: URL(fileURLWithPath: audioPath))
            try player1 = AVAudioPlayer(contentsOf: URL(fileURLWithPath: audioPath1))

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

Answer 1

当然你不能循环执行!

一个接一个地播放声音文件的正确方法是使用AVAudioPlayerDelegate。

在你的 View Controller 中，符合AVAudioPlayerDelegate:

class YourViewController: UIViewController, AVAudioPlayerDelegate {
    // ...
    func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer,
                         successfully flag: Bool) {

    }
}

如您所见，我向 Controller 添加了一个 audioPlayerDidFinishPlaying 方法。

所以你想先玩player，然后再玩player1，对吧？

在viewDidLoad中，添加这一行:

player.delegate = self

在我刚刚添加的方法中，写:

player1.play()

其他的 IBAction 方法应该稍微改变一下:

@IBAction func play(_ sender: AnyObject) {
       player.play()
}

@IBAction func pause(_ sender: AnyObject) {
    if player.isPlaying {
        player.pause()
    } else if player1.isPlaying {
        player1.pause()
    }

}
@IBAction func stop(_ sender: AnyObject) {
    if player.isPlaying {
        player.stop()
    } else if player1.isPlaying {
        player1.stop()
    }
}
@IBAction func sliderChanged(_ sender: AnyObject) {
    player.volume = sliderValue.value 
    player1.volume = sliderValue.value
}