Strange Swift Timer sequence

1

I am not sure if its “me” or a bug or what…

Tell me if this makes sense (from a logical point of view)

I need t fire an event (via a delegate) every 1, 3 and 7 seconds

So what I did was create a class (shown here in Pseudo code)

class MyTimer {
init() { setTimer(7) } // number is seconds

// this is supposed to initialize a ONE SHOT time that waits "sec"
private func setTimer(sec : Double) {
self.delegate.timer(sec) // fire event to notifiy of current interval
let _ = Timer.scheduledTimer(withTimeInterval: color.period(), repeats: false) {_ in self.changeTimer(sec) }
}

// when time elapsed, set next interval
private changeTimer(sec:double) {
switch sec{
case 1 : t = 3
case 3 : t = 7
case 7 : t = 1
}
setTimer(t)
}

the problem is… it calls SetTimer 2x in a row (0.02 seconds apart)

so it comes out
7 7 1 1 3 3 7 7 1 1 3 3
7 seconds 0.02 seconds 1 second .02 seconds 3 seconds .02 seconds etc.
not
7 1 3 7 1 3

does anyone see a flaw in my logic

2

Turns out I was creating the parent object twice… so it started two instances of the timer sequence, and since the sequences where created 0.02 seconds apart that accounted for the double counting, and slight offset.