Xcode swift - 未解決的標識符錯誤

Question

請幫我編輯我的代碼。我似乎無法解決這個錯誤。

import UIKit 
import AVKit 
import AVFoundation 
import MediaPlayer 

class ViewController: UIViewController { 

    let avPlayerViewControler = AVPlayerViewController() 
    var avPlayer:AVPlayer? 
    var videoNumber:Int! 
    var url:String! 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     let urlpathString:String? = NSBundle.mainBundle().pathForResource("url", ofType: "mp4") 

     if let urlPath = urlpathString { 

      switch videoNumber { 
      case 1 : url="20" 
      case 2 : url="10" 
      default : break 
      } 
      let movieUrl = NSURL(fileURLWithPath: urlPath) 

     } 
     self.avPlayer = AVPlayer(URL: movieUrl) 
     self.avPlayerViewControler.player = self.avPlayer 

    } 

    @IBAction func Cool(sender: UIButton) { 
     videoNumber=1 
    } 
} 

Answer 1

你有關於avPlayer和avPlayerViewControler的if內的兩個線移動，因爲不斷movieUrl僅僅是範圍內可用的 - 它只存在它是在限定的範圍內，它不存在在if之外 - 塊！

override func viewDidLoad() { 
    super.viewDidLoad() 

    let urlpathString:String? = NSBundle.mainBundle().pathForResource("url", ofType: "mp4") 

    if let urlPath = urlpathString { 

     switch videoNumber { 
      case 1 : url="20" 
      case 2 : url="10" 
      default : break 
     } 
     let movieUrl = NSURL(fileURLWithPath: urlPath) 
     self.avPlayer = AVPlayer(URL: movieUrl) 
     self.avPlayerViewControler.player = self.avPlayer 
    } 
}