value from func from other viewController - ios

Question

I'm trying to write simple clicker but I have some problem, on "StartViewController" I have func value() it add per sec 1 + click 1 + last save value and I have shopViewController on the shopViewController I have button when I press it it must give +1(every time) to click but how can I access to current value from func value()? When I try get current value I get nil
func value() -> Float {
let endValue = appPerSec + valueToLoad + click
valueToSave = endValue
valueLable.text = "\(endValue)"
return valueToSave
}
// shopViewController
var StartView:StartViewController!
var currentValue:Float! = 0.0
#IBAction func testAdd(_ sender: Any) {
currentValue = StartView.value // here I get NIL
print(currentValue)
}

Answer 1

i did not UnderStand your question but i can give solution in parts for the terms i can read, or please improve your question so that i can understand exactly what you are looking for.
meanwhile i'll just give some concepts that i think you are looking for, if not useful please edit your question before rating not useful :
to make a timer you can use
#IBOutlet weak var timeInTimer: UILabel!
var timer = Timer()
#IBAction func buttonPressed(_ sender: Any) //to stop the timer
{
timer.invalidate()
}
#IBAction func playButtonPressed(_ sender: Any) //to start the timer
{
timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(ViewController.processTimer), userInfo: nil, repeats: true)
}
To pass data from one view to other view :
let anyObjectName = storyboard?.instantiateViewController(withIdentifier: "IdentifierOfSecondViewController") as! IdentifierOfSecondViewController
anyObjectName.userName = userName //where username is a variable in second view

Answer 2

You can use Delegate and Protocols. Above your shopView add:
protocol ShopProtocol{
func updateCount();
}
In your shopView add:
var delegateShop:ShopProtocol?
And when you change that variable, go to:
delegateShop.updateCount()
In your main view controller, when you present this shopViewController (before presenting it), add:
shopController.delegateShop = self
And change your ViewController definition to
class ...: UIViewController, ..., ShopProtocol{
And, of course, create in that view controller:
func updateCount(){
//do Stuff
}