Swift 2迁移问题

我刚刚在Xcode 7testing版中打开了我的旧项目。 代码在Xcode 6中工作得很好，但是现在显示了很多错误。 我不知道这是什么，有谁能解释为什么发生这种情况，以及如何解决这个问题？谢谢！

import UIKit import AVFoundation class ViewController: UIViewController { var player: AVAudioPlayer = AVAudioPlayer() @IBOutlet weak var firstCardImageView: UIImageView! @IBOutlet weak var secondCardImageView: UIImageView! @IBOutlet weak var label: UILabel! var cardNamesArray:[String] = ["dice1","dice2","dice3","dice4","dice5","dice6"] override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib. } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() // Dispose of any resources that can be recreated. } @IBAction func rollaction(sender: AnyObject) { updateAction() } func updateAction(){ var firstRandomNumber = Int(arc4random_uniform(5)) var firstCardString:String = String(self.cardNamesArray[firstRandomNumber]) var secondRandomNumber = Int(arc4random_uniform(5)) var secondCardString:String = String(self.cardNamesArray[secondRandomNumber]) self.firstCardImageView.image = UIImage(named: firstCardString) self.secondCardImageView.image = UIImage(named: secondCardString) var fileLocation = NSBundle.mainBundle().pathForResource("sound", ofType: ".mp3") var error: NSError? = nil player = AVAudioPlayer(contentsOfURL: NSURL(fileURLWithPath: fileLocation!), error: &error) //Error: Cannot find an initializer for type 'AVAudioPlayer' that accepts an argument list of type '(contentsOfURL: NSURL, error: inout NSError?)' AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryAmbient, error: nil) //Error:Extra argument 'error' in call AVAudioSession.sharedInstance().setActive(true, error: nil) //Error:Extra argument 'error' in call player.play() let num = firstRandomNumber + secondRandomNumber + 2 self.label.text = "The sum is \(num)" } override func motionEnded(motion: UIEventSubtype, withEvent event: UIEvent) { if event.subtype == UIEventSubtype.MotionShake { //Error:Method does not override any method from its superclass updateAction() } } } 

Answer 1

这里是你的updateAction（）函数与Swift 2.0的do / try / catch实现：

 func updateAction(){ var firstRandomNumber = Int(arc4random_uniform(5)) var firstCardString:String = String(self.cardNamesArray[firstRandomNumber]) var secondRandomNumber = Int(arc4random_uniform(5)) var secondCardString:String = String(self.cardNamesArray[secondRandomNumber]) self.firstCardImageView.image = UIImage(named: firstCardString) self.secondCardImageView.image = UIImage(named: secondCardString) let fileLocation = NSBundle.mainBundle().pathForResource("sound", ofType: ".mp3") do { player = try AVAudioPlayer(contentsOfURL: NSURL(fileURLWithPath: fileLocation!)) try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryAmbient) try AVAudioSession.sharedInstance().setActive(true) } catch { print("Something bad happened. Try catching specific errors to narrow things down") } player.play() let num = firstRandomNumber + secondRandomNumber + 2 self.label.text = "The sum is \(num)" }