swift if statement, condition will never be executed : I thought I was good with if statements but apparently Im still missing something. In the following the **timer.invalidate()** line returns a "**Will never be executed**". As far as I can tell my syntax is correct..
xcode 9 beta6

    @IBAction func button(_ sender: Any) {
     
            let timer = Timer.scheduledTimer(timeInterval:0.2 , target: self, selector: #selector(ViewController.imageSwitch) , userInfo: nil, repeats: true)

        var buttonState = false
        
        if buttonState == true {
            timer.invalidate()
            buttonState = false
        }
        if buttonState == false {
            timer.fire()
            buttonState = true
        }
    }