SWIFT - Multiple NSTimers - timer

Question

I have run in to a slight problem when trying to manage multiple NSTimers in SWIFT. No matter what I Try it will only ever invalidate the last timer I create. But I need to be able to invalidate any of the timers by choice.
Is there some way to create a reference ID that I could then use to select the specific NSTimer I want to invalidate? Any help would be great.
here is a snippet of my code.
import UIKit
var myTimer:NSTimer!
class TimerManager: NSObject {
}
public class Timer {
// each instance has it's own handler
private var handler: (timer: NSTimer) -> () = { (timer: NSTimer) in }
public class func start(duration: NSTimeInterval, repeats: Bool, handler:(timer: NSTimer)->()) {
var t = Timer()
t.handler = handler
myTimer = NSTimer.scheduledTimerWithTimeInterval(duration, target: t, selector: "processHandler:", userInfo: nil, repeats: repeats)
}
#objc private func processHandler(timer: NSTimer) {
self.handler(timer: timer)
}
}
class countdown{
//handles the countdown for the timer and invalidates when it reaches 0
var y = 0
func begin(length:Int) {
y = length
let delta = 1
let delay = 1.0
Timer.start(delay, repeats: true) {
(t: NSTimer) in
self.y -= delta
println(self.y)
if (self.y <= 0) {
t.invalidate()
}
}
}
func end () {
println("timer stopped")
myTimer.invalidate()
}
}
And I create the timer like so:
countdownTimer.begin(120) //time length in seconds ... 120 = 2 mins
To stop timer:
countdownTimer.end()

Answer 1

You may create a dictionary retaining NSTimer objects. Note that timerManager needs to be defined at global scope. Hope it shed light.
class TimerManager {
var _timerTable = [Int: NSTimer]()
var _id: Int = 0
/*! Schedule a timer and return an integer that represents id of the timer
*/
func startTimer(target: AnyObject, selector: Selector, interval: NSTimeInterval) -> Int {
var timer = NSTimer.scheduledTimerWithTimeInterval(interval, target: target, selector: selector, userInfo: nil, repeats: true)
_id += 1
_timerTable[_id] = timer
return _id
}
/*! Stop a timer of an id
*/
func stopTimer(id: Int) {
if let timer = _timerTable[id] {
if timer.valid {
timer.invalidate()
}
}
}
/*! Returns timer instance of an id
*/
func getTimer(id: Int) -> NSTimer? {
return _timerTable[id]
}
}
// This needs to be delcared at global scope, serving as "singleton" instance of TimerManager
let timerManager = TimerManager()
Following code creates a new timer.
var aTimer = timerManager.startTimer(self, selector: Selector("timerFunction"), interval: 1)
To stop the timer, simply pass id to stopTimer(id: Int).
/* Code ... */
timerManager.stopTimer(aTimer)
Also note getTimer method returns the actual instance with an id.
Regards