我正在嘗試播放聲音，AVAudioPlayer但無法正常工作。編輯1：仍然行不通。編輯2：此代碼有效。我的設備處于靜音模式。import UIKitimport AVFoundationclass ViewController: UIViewController {    var audioPlayer = AVAudioPlayer()    override func viewDidLoad() {        super.viewDidLoad()        var alertSound = NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource("button-09", ofType: "wav"))        println(alertSound)        var error:NSError?        audioPlayer = AVAudioPlayer(contentsOfURL: alertSound, error: &error)        audioPlayer.prepareToPlay()        audioPlayer.play()    }}