Xcode: instantiating a view controller with custom variable

January 9, 2023

So I want to instantiate a view controller from storyboard and change it’s static variables…

this is "vc1" – the view controller to be instantiated:

import UIKit

class vc1: UIViewController {
    @IBOutlet weak var lbl_title: UILabel!
    
    static var title = "initial value"
    
    override func viewDidLoad() {
        super.viewDidLoad()

        lbl_title.text = vc1.title
    }
}

And this is my root vc…

import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var btn_go: UIButton!
    
    @IBAction func btn_gogogo(_ sender: Any) {
        
        let vc = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "vc1") as! vc1
        
        vc.title = "bla"

        self.present(vc, animated: true, completion: nil)
    }

}

here I’m trying to change the static variable of the view controller that I just instantiated…
with no effect… the variable ( in my case ‘title’ ) is always stuck to it’s initial value…

What is the problem here ?

Best

Mark

>Solution :

Don’t try to override the view controller’s title property. Instead, create your own:

class vc1: UIViewController {
    @IBOutlet weak var lbl_title: UILabel!
    
    var myTitle = "initial value"
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        lbl_title.text = myTitle
    }
}

class ViewController: UIViewController {
    
    @IBOutlet weak var btn_go: UIButton!
    
    @IBAction func btn_gogogo(_ sender: Any) {
        
        let vc = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "vc1") as! vc1
        
        vc.myTitle = "bla"
        
        self.present(vc, animated: true, completion: nil)
    }
    
}