Why does my timer starts at 4:00:00 ?

Question

My Timer is starting at 4:00:00 while I want it to start at 0:00:00.

At the beginning I was using "mm:ss" as a dateFormatter, but it was problematic because as soon as my timer gets to 60 min, it restarts from 0.

I wanted my timer to keep going over 60min so I added "hh:mm:ss", but now my timer is starting at 4:00:00 instead of 0:00:00.

var timer = NSTimer()
var sec = 0

override func viewDidAppear(animated: Bool) {
    super.viewDidAppear(animated)
    timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("updateTheTime"), userInfo: nil, repeats: true)
  }

func theTime(interval:NSTimeInterval) -> String {
    var dateFormatter = NSDateFormatter()
    var date = NSDate(timeIntervalSince1970: interval)
    dateFormatter.dateFormat = "h:mm:ss"
    return dateFormatter.stringFromDate(date)
  }

func updateTheTime(){
    sec++
    self.timeElapsed.text = self.theTime(Double(sec))
  }

Answer 1

You can remedy this by specifying the time zone for the formatter:

 dateFormatter.timeZone = NSTimeZone(forSecondsFromGMT: 0)

Frankly, though, I'd advise against manually counting seconds yourself, and instead save the start time and then use NSDateComponentsFormatter to format a nice counter:

var timer: NSTimer?
var startTime: NSDate!

var formatter: NSDateComponentsFormatter = {
    let _formatter = NSDateComponentsFormatter()
    _formatter.allowedUnits = .CalendarUnitHour | .CalendarUnitMinute | .CalendarUnitSecond
    _formatter.zeroFormattingBehavior = .Pad
    return _formatter
}()

func startTimer() {
    startTime = NSDate()
    timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: "handleTimer:", userInfo: nil, repeats: true)
}

func stopTimer() {
    timer?.invalidate()
    timer = nil
}

func handleTimer(timer: NSTimer) {
    timeElapsed.text = formatter.stringFromDate(startTime, toDate: NSDate())
}