Using an NSTimer in Swift

Question

In this scenario, timerFunc() is never called. What am I missing?

class AppDelegate: NSObject, NSApplicationDelegate {

    var myTimer: NSTimer? = nil

             


        

Answer 1

You can create a scheduled timer which automatically adds itself to the runloop and starts firing:

Swift 2

NSTimer.scheduledTimerWithTimeInterval(0.5, target: self, selector: "timerDidFire:", userInfo: userInfo, repeats: true)

Swift 3, 4, 5

Timer.scheduledTimer(withTimeInterval: 0.5, target: self, selector: #selector(timerDidFire(_:)), userInfo: userInfo, repeats: true)

Or, you can keep your current code, and add the timer to the runloop when you're ready for it:

Swift 2

let myTimer = NSTimer(timeInterval: 0.5, target: self, selector: "timerDidFire:", userInfo: nil, repeats: true)
NSRunLoop.currentRunLoop().addTimer(myTimer, forMode: NSRunLoopCommonModes)

Swift 3, 4, 5

let myTimer = Timer(timeInterval: 0.5, target: self, selector: #selector(timerDidFire(_:)), userInfo: nil, repeats: true)
RunLoop.current.add(myTimer, forMode: RunLoop.Mode.common)