loops - Looping Label Change Backround tast in Swift -

i'm new swift , looking way loop changing label cycles trough array of strings. ways i've tried have stopped other tasks while loop running.

you're view controller this:

class viewcontroller: uiviewcontroller {      @iboutlet weak var cyclelabel: uilabel!      var strings: [string]!     var timer: nstimer!     var index: int = 0      override func viewdidload() {         super.viewdidload()         self.strings = ["lorem", "ipsum", "dolor", "sit", "amet", "consectetur", "adipiscing", "elit", "vestibulum", "erat", "lacus", "congue"]     }      override func viewwillappear(animated: bool) {         super.viewwillappear(animated)         self.cyclelabel.text = self.strings[self.index]     }      @ibaction func begincyclingtapped(sender: uibutton) {         let interval = 1.0          if self.timer.valid {             self.timer.invalidate()         }          self.timer = nstimer.scheduledtimerwithtimeinterval(interval, target: self, selector: "updatelabel", userinfo: nil, repeats: true)     }      func updatelabel() {         self.index += 1         self.cyclelabel.text = self.strings[self.index % self.strings.count]     }  } 

this code update label text next string in strings property every 1 second. if you'd different interval, change interval constant in begincyclingtapped(:) method. label start restart beginning of strings array after reaches last element in array. if statement in begincyclingtapped(:) ensures multiple timers not scheduled update label, result in label getting updated more desired. also, make sure hook iboutlet uilabel on storyboard.