Sigabrt swift Xcode (making a timer) - xcode

Question

I'm trying to make a stopwatch, and I can't seem to understand why I am getting a sigabrt with my application. Sorry I didn't know what to include, so I included everything.
var timer = NSTimer()
var minutes: Int = 0
var seconds: Int = 0
var fractions: Int = 0
var startStopWatch: Bool = true
var StopwatchString: String = ""
#IBOutlet weak var display: UILabel!
#IBAction func start(sender: UIButton) {
if startStopWatch == true {
NSTimer.scheduledTimerWithTimeInterval(0.01, target: self, selector: Selector("updateStopwatch"), userInfo: nil, repeats: true)
startStopWatch = false
} else {
timer.invalidate()
startStopWatch = true
}
}
#IBAction func reset(sender: UIButton) {
}
override func viewDidLoad() {
super.viewDidLoad()
display.text = "00:00.00"
}
func updateStopWatch() {
fractions += 1
if fractions == 100 {
seconds += 1
fractions = 0
}
if seconds == 60 {
minutes += 1
seconds = 0
}
let fractionsString = fractions > 9 ? "\(fractions)" : "0\(fractions)"
let secondsString = seconds > 9 ? "\(seconds)" : "0\(seconds)"
let minutesString = minutes > 9 ? "\(minutes)" : "0\(minutes)"
StopwatchString = "\(minutesString):\(secondsString).\(fractionsString)"
display.text = StopwatchString
}

Answer 1

I cut and pasted your code into a project and when I tapped the start button the first line of the error message said:
-[My.ViewController updateStopwatch]: unrecognized selector sent to instance 0x7fe0034b3520
That tells you all you need to know. You send the updateStopwatch message to your view controller but it doesn't implement that method. I noticed though that your ViewController does implement an updateStopWatch method. Looks like a basic capitalization error to me.
Always, always, always, read at least the first line of the error message.

Answer 2

Here are some fixes:
+I changed the timer variable initially to nil - it will be saved in the start function.
+Your if statement in the start function looked like this:
if startStopWatch == true
But it should be like this:
if (startStopWatch)
Hope this helpes :)
var timer = nil
var minutes = 0
var seconds = 0
var fractions = 0
var startStopWatch = true
var StopwatchString = ""
#IBOutlet weak var display: UILabel!
#IBAction func start(sender: UIButton) {
if (startStopWatch == true) {
timer = NSTimer.scheduledTimerWithTimeInterval(0.01, target: self, selector: Selector("updateStopwatch"), userInfo: nil, repeats: true)
startStopWatch = false
//I added one thing. If the start button is pushed the text will change to stop. You can change this if you like.
sender.setTitle("Stop", forState: .Normal)
//
} else {
timer.invalidate()
startStopWatch = true
}
}
#IBAction func reset(sender: UIButton) {
display.text! = "00:00.00"
}
override func viewDidLoad() {
super.viewDidLoad()
display.text! = "00:00.00"
}
func updateStopWatch() {
fractions++
if (fractions == 100) {
seconds++
fractions = 0
}
if (seconds == 60) {
minutes++
seconds = 0
}
var fractionsString = fractions > 9 ? "\(fractions)" : "0\(fractions)"
var secondsString = seconds > 9 ? "\(seconds)" : "0\(seconds)"
var minutesString = minutes > 9 ? "\(minutes)" : "0\(minutes)"
StopwatchString = "\(minutesString):\(secondsString).\(fractionsString)"
display.text! = StopwatchString
}