ios - "ViewController.Type does not have a member named ' 变量

Question

我一直在 IOS 上使用 Swift 开发应用程序，当您按下按钮时它会发出声音(我是初学者)。
这段代码虽然一直给我带来问题，但当我刚刚输入“The Wilhelm 尖叫音效”时，该代码有效，但是当我尝试输入字符串时，它给了我“ViewController.Type 没有名为尖叫的成员”错误.

我已经坚持了一段时间，所以任何帮助将不胜感激。

class ViewController: UIViewController {

required init(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}


let scream: String = "The Wilhelm scream sound effect"



var pianoSound = NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource(scream, ofType: "mp3")!)
var audioPlayer = AVAudioPlayer()
}

Answer 1

你的代码在那里不起作用。你必须把它放在一个函数中，如下所示:

let audioPlayer = AVAudioPlayer()
let scream = "The Wilhelm scream sound effect"
func playMySound(sound:String) {
    // you can get the file url instead of the path like this:
    let soundUrl = NSBundle.mainBundle().URLForResource(sound, withExtension: "mp3")
    // now you can play your audio using the soundUrl
    // ...        
}

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    playMySound("The Wilhelm scream sound effect")
    // or
    playMySound(scream)
}