Swift Transferring data to the first view by pressing the "Back" button - swift

Question

Hello friends . Navigation control to the second screen. I need to go
to the one screen with the button(Sonucları Listele) on the second screen and I have to
make the number on the first screen to "2"
image 1
image 2
First View
class KonularViewController: UIViewController {
var number : Int?
#IBAction func barButtonKonuEkle(_ sender: Any) {
let childViewController = storyboard?.instantiateViewController(withIdentifier: "KonuEkleViewController") as! KonuEkleViewController
navigationController?.pushViewController(childViewController, animated: true)
}
}
Second View
class AramaViewController: UIViewController {
#IBOutlet weak var btn1: UIButton!
#IBOutlet weak var btn2: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
btn1.isSelected = true
}
#IBAction func btnListele(_ sender: Any) {
//First View "Number" variable on the first screen will be 2
}
#IBAction func btn_box(sender: UIButton) {
if sender.titleLabel?.text == "En Yeniler"
{
btn1.isSelected = true
btn2.isSelected = false
}
else
{
btn2.isSelected = true
btn1.isSelected = false
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}

Answer 1

One strategy would be to have a 3rd class that is your Model, which can hold state.
class Model {
static let shared = Model()
var count: Int = 1
}
class AramaViewController: UIViewController {
#IBAction fund btnListele(_ sender: Any) {
Model.shared.count += 1
//First View "Number" variable on the first screen will be 2
}
class KonularViewController: UIViewController {
override func viewWillAppear(animated:Bool) {
super.viewWillAppear(animated: animated)
numberView.text = "\(Model.shared.count)" //display your number here
}
}
Another Option
Reach back in the Navigation Controller View Controllers array to the previous view and set a property. This is a bit more fragile.
class KonularViewController: UIViewController {
var count: Int = 1
override func viewWillAppear(animated:Bool) {
super.viewWillAppear(animated: animated)
numberView.text = "\(count)" //display your number here
}
}
class AramaViewController: UIViewController {
#IBAction fund btnListele(_ sender: Any) {
let numberOfViews = navigationController.viewControllers.count
if count > 1, let previousViewController = self.navigationController.viewControllers[numberOfViews-2] as? KonularViewController
previousViewController.count += 1
//First View "Number" variable on the first screen will be 2
}

Answer 2

Assuming KonularViewController identifier is "KonularViewController".
In AramaViewController:
#IBAction func btnListele(_ sender: Any) {
//First View "Number" variable on the first screen will be 2
let konularViewController = storyboard?.instantiateViewController(withIdentifier: "KonularViewController") as! KonularViewController
konularViewController.number = 2
navigationController?.pushViewController(childViewController, animated: true)
}