Xcode 7/Swift 2 Extra argument 'error' in call [duplicate] - ios

Question

I just opened my old project in Xcode 7 beta. The code works perfectly fine in Xcode 6, but now it's showing many error. I don"t know what those are. Can anybody explain why this happened, and how to fix it? Thank you! Here is the Code
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

Here's your updateAction() function with Swift 2.0's do/try/catch implementation:
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)"
}