Question

我刚刚开始在iOS中开发并试图创建一个简单的应用程序，当我按下按钮时会一次又一次地改变图像和播放声音，但在运行时会一直出现错误。

错误“致命错误：在展开Optional值时意外发现nil （LLDB）“

这是我的“view controller.swift”

import UIKit
import AVFoundation

class ViewController: UIViewController {

let image0 = UIImage(named: "button.png")
let image1 = UIImage(named: "buttonPressed.png")

var sound = NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource("sound", ofType: "m4a")!)
var player = AVAudioPlayer()

@IBOutlet weak var clicker: UIButton!

@IBAction func clickerPressed(sender: UIButton) {

    sender.setImage(image1, forState:.Highlighted)

    player.stop()
    player.currentTime = 0
    player.play()

}

override func viewDidLoad() {
    super.viewDidLoad()

    clicker.setImage(image0, forState:.Normal)
    clicker.setImage(image1, forState:.Highlighted)

    player = AVAudioPlayer(contentsOfURL: sound, error: nil)
    player.prepareToPlay()

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()

}

}

Answer 1

谢谢你，迈克尔。问题解决了。显然原始的.m4a文件有问题。我将它转换为.mp3，一切都很好。

Swift - 音频 - 按钮声音不断出现错误

1 个答案: