Swift技术问题：无法按数组顺序依次播放音频序列

你的问题其实很典型——当你在循环里直接创建并播放AVAudioPlayer时，循环会瞬间执行完毕，而AVAudioPlayer.play()是异步操作，不会阻塞当前线程。这就导致每次循环都会覆盖之前的audioPlayer实例，最后只有数组里最后一个元素对应的音频会被实际播放，前面的还没来得及启动就被替换掉了。

下面给你两种可行的解决思路，你可以根据自己的需求选择：

方案一：递归+AVAudioPlayer代理（适合需要精细控制每个播放环节） #

这种方式会在前一个音频播放完成后，自动启动下一个，完美符合你“依次播放后停止”的需求：

1. 首先在你的控制器里添加几个变量：

import UIKit
import AVFoundation

class UIController: UIViewController {
    var audioPlayer: AVAudioPlayer!
    let soundSeq = [1, 2, 3, 4, 5] // 替换成你的实际数组
    var currentPlayIndex = 0 // 跟踪当前播放的位置

2. 实现一个递归播放的函数：

func playNextSound() {
    // 先判断是否已经播放完所有音频
    guard currentPlayIndex < soundSeq.count else {
        currentPlayIndex = 0 // 播放完可以重置索引，或者做其他收尾操作
        return
    }
    
    let tagId = soundSeq[currentPlayIndex]
    var audioURL: URL?
    
    // 这里替换成你实际的音频文件匹配逻辑
    switch tagId {
    case 1:
        audioURL = Bundle.main.url(forResource: "sound1", withExtension: "mp3")
    case 2:
        audioURL = Bundle.main.url(forResource: "sound2", withExtension: "mp3")
    case 3:
        audioURL = Bundle.main.url(forResource: "sound3", withExtension: "mp3")
    case 4:
        audioURL = Bundle.main.url(forResource: "sound4", withExtension: "mp3")
    case 5:
        audioURL = Bundle.main.url(forResource: "sound5", withExtension: "mp3")
    default:
        audioURL = nil
    }
    
    guard let url = audioURL else {
        // 如果当前tagId没有对应音频，直接跳到下一个
        currentPlayIndex += 1
        playNextSound()
        return
    }
    
    do {
        audioPlayer = try AVAudioPlayer(contentsOf: url)
        audioPlayer.delegate = self // 设置代理监听播放完成
        audioPlayer.play()
    } catch {
        print("音频播放失败：\(error.localizedDescription)")
        currentPlayIndex += 1
        playNextSound()
    }
}

3. 遵守AVAudioPlayerDelegate协议，在播放完成时触发下一个音频：

extension UIController: AVAudioPlayerDelegate {
    func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) {
        currentPlayIndex += 1
        playNextSound()
    }
}

4. 最后在Play按钮的点击事件里启动播放：

@IBAction func playButtonTapped(_ sender: UIButton) {
    currentPlayIndex = 0 // 每次点击都从数组开头开始
    playNextSound()
}

方案二：使用AVQueuePlayer（适合简单的顺序播放需求） #

如果你不需要对每个音频的播放过程做精细控制，AVQueuePlayer是更简单的选择——它本身就是用来按顺序播放多个媒体资源的：

func playSoundSequence() {
    var playerItems: [AVPlayerItem] = []
    
    for tagId in soundSeq {
        var audioURL: URL?
        // 同样替换成你的音频匹配逻辑
        switch tagId {
        case 1:
            audioURL = Bundle.main.url(forResource: "sound1", withExtension: "mp3")
        case 2:
            audioURL = Bundle.main.url(forResource: "sound2", withExtension: "mp3")
        case 3:
            audioURL = Bundle.main.url(forResource: "sound3", withExtension: "mp3")
        case 4:
            audioURL = Bundle.main.url(forResource: "sound4", withExtension: "mp3")
        case 5:
            audioURL = Bundle.main.url(forResource: "sound5", withExtension: "mp3")
        default:
            audioURL = nil
        }
        
        if let url = audioURL {
            playerItems.append(AVPlayerItem(url: url))
        }
    }
    
    let queuePlayer = AVQueuePlayer(items: playerItems)
    queuePlayer.play()
}

然后在按钮点击事件里调用这个函数即可：

@IBAction func playButtonTapped(_ sender: UIButton) {
    playSoundSequence()
}

这两种方案都能解决你当前只播放最后一个音频的问题，你可以根据自己的实际需求来选择~

内容的提问来源于stack exchange，提问作者Chelseawillrecover