AVAudio播放器在模拟器中播放录制的音频，但不在手机上播放

Question

我正在尝试创建一个仅录制和播放音频的应用程序。我已经尝试了多种不同的音频播放方法，但在iPhone 6和iPhone 8 Plus上播放时似乎不起作用，但在模拟器上工作。

错误：

线程 1：致命错误：解开可选值时意外发现 nil

当 SoundPlayer 尝试播放时会发生这种情况。控制台中打印的错误是：

Error Domain=NSOSStatusErrorDomain Code=2003334207 "(null(">

@IBOutlet weak var recordBtn: UIButton!
@IBOutlet weak var playBtn: UIButton!
var soundRecorder : AVAudioRecorder!
var soundPlayer : AVAudioPlayer!
var fileName = "audioFile0.aac"

var screenCounter = 0(全局变量(

override open func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}
override open func viewDidLoad() {
    super.viewDidLoad()
    if (screenCounter == 0){
    // Do any additional setup after loading the view, typically from a nib.
        setupRecorder()
        screenCounter += 1
    }
}

func setupRecorder(){
    let recordSettings = [ AVFormatIDKey : kAudioFormatMPEG4AAC
        , AVEncoderAudioQualityKey : AVAudioQuality.max.rawValue, AVEncoderBitRateKey : 320000, AVNumberOfChannelsKey : 2, AVSampleRateKey : 44100.0 ] as [String : Any]
    let _ : NSError?
    do{
        soundRecorder = try AVAudioRecorder(url : getFileURL() as URL, settings : recordSettings)
    }catch{
        print("Something went wrong")
    }
    soundRecorder.delegate = self
    soundRecorder.prepareToRecord()
}
func getCacheDirectory() -> String{
    let paths = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory, FileManager.SearchPathDomainMask.userDomainMask, true)
     return paths[0]
}
func getFileURL() -> NSURL{
    let pathURL = NSURL(fileURLWithPath : getCacheDirectory()).appendingPathComponent(fileName)
    let pathString = pathURL?.path
    let filePath = NSURL(fileURLWithPath : pathString!)
    return filePath
}

@IBAction func record(_ sender: UIButton) {
    if sender.titleLabel?.text == "Record"{
        soundRecorder.record()
        sender.setTitle("Stop", for : .normal)
        playBtn.isEnabled = false
    }else{
        soundRecorder.stop()
        sender.setTitle("Record", for : .normal)
        playBtn.isEnabled = false
    }
}
@IBAction func playSound(_ sender: UIButton) {
    if sender.titleLabel?.text == "Play"{
            recordBtn.isEnabled = false
            sender.setTitle("Stop", for : .normal)
            preparePlayer()
            soundPlayer.play()
    }else{
        soundPlayer.stop()
        sender.setTitle("Play", for : .normal)
    }
}
func preparePlayer(){
    let _ : NSError?
    do{
        soundPlayer = try AVAudioPlayer(contentsOf : getFileURL() as URL)
    }catch{
        print(error)
    }
    soundPlayer.delegate = self
    soundPlayer.prepareToPlay()
    soundPlayer.volume = 1.0
}

open func audioRecorderDidFinishRecording(_ recorder: AVAudioRecorder, successfully flag: Bool) {
    playBtn.isEnabled = true
}
open func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) {
    recordBtn.isEnabled = true
    playBtn.setTitle("Play", for : .normal)
}

任何帮助将不胜感激。

更新

感谢您的所有建议！我最终在这里的另一个论坛上发现了错误。似乎在录制和播放音频之间需要一个中介，称为音频会话。

Answer 1

尝试在

playSoung方法之外初始化soundPlayer。

var soundPlayer = AVAudioPlayer()
func preparePlayer() {
    ...
}

Answer 2

似乎音频文件网址为零。你会尝试使用这个文件管理器吗

//func to give path(URL) to store the recording
    func getDirectory() -> URL {
        let path = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
        let docDirectory = path[0]
        return docDirectory
    }

并且您的文件 URL 完整路径应为：

let path =   getDirectory().appendingPathComponent(fileName)

注意：由于我无法运行和测试您的代码，因此我不确定解决方案。让我知道结果。否则，我将删除我的帖子。