Button Title Resetting to Default After Change

Question

After changing a button title, the title correctly changes based on a pickerView. Then I when I click on a different page in the app and come back, the button title reverts back to its defaults When I try to change it again, it goes to its correct new changed title as soon as the pickerView pops up. Why is this happening and how do I fix it?

Here's the code for the button title I want to change when the user chooses a row in the pickerView -

  @IBAction func roleButton(sender: UIButton) {
    sender.setTitle(Manager.roleText, forState: UIControlState.Normal)
}

And here's the pickerView code -

var Array = ["A", "B", "C", "D", "E"]

var Placement = 0

@IBOutlet var rolePicker: UIPickerView!

override func viewDidLoad() {
    super.viewDidLoad()

    rolePicker.delegate = self
    rolePicker.dataSource = self
}

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {
    return Array[row]
}

func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    return Array.count
}

func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {

    return 1
}

@IBAction func Submit(sender: AnyObject) {
    if Placement == 0 {
        Manager.roleText = Array[0]
    }
    else if Placement == 1 {
        Manager.roleText = Array[1]
    }
    else if Placement == 2 {
        Manager.roleText = Array[2]
    }
    else if Placement == 3 {
        Manager.roleText = Array[3]
    }
    else if Placement == 4 {
        Manager.roleText = Array[4]
    }


}

func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    Placement = row
}

Answer 1

I believe that, if there are no references to the ViewController with the button on it, it's destroyed to free up memory as soon as you leave it. (That is, as soon as there are no more references to it). If you pass a reference to ViewController1 to ViewController2 (e.g. segue.destinationViewController.delegate = self) during prepareForSegue, it should preserve it so you can come back to it.