Change Label text in a ContainerView on click of a button from other class (Uiviewcontroller)

Question

I got small containerView with UILabel on main app screen. I got UIButton on main UIViewController. I want to change text of label that belongs to containerView class by clicking button in UIViewController. I try to make it with delegation, but for some reason i got a mistake (Unwraping optional)...

I try to make it with Protocol, bud method "addText" in ContView dont works((((((

    class ViewController: UIViewController {

var delegate: DelegateProtocol?

override func viewDidLoad() {
    super.viewDidLoad()

}


@IBAction func button(_ sender: Any) {

delegate?.addText(String2: "123")

}}

///////////////////////////////////////////////////////////////////////

   protocol DelegateProtocol {

    func addText(String2: String)
}

//////////////////////////////////////////////////////////////////////

class ContViewController: UIViewController, DelegateProtocol {


    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "con" {

            let vc = segue.destination as! ViewController
            vc.delegate = self
        }
    }


    func addText(String2: String) {

        label.text = String2

    }


    @IBOutlet weak var label: UILabel!


    override func viewDidLoad() {
        super.viewDidLoad()

    }

}

Error is the method addText is dont execute in ContViewController from button touchUp inside in ViewController class... — Ixar, Jul 21 '18 at 13:32

score 1 · Accepted Answer · edited Jul 19 '18 at 08:01

1

first make an global variable in your view controller

private var viewController: YourVC?

then give your container view segue an identifier and do follwing

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "yourviewcontroller Segue identifiew" {  //your container view segue identifier
        viewController = segue.destination as? SelectedImageVC
    }
}

now you can use you viewController to access label in your containerview controller like

if let controller = viewController {
    controller.yourlabel.text = "text you want"
}

edited Jul 19 '18 at 08:01

pacification

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answered Jul 19 '18 at 05:28

Devil Decoder

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Bro, your code dont work... Or maybe i do somrthing wrong. – Ixar Jul 21 '18 at 08:00
Bro your code dont help me, but i accept your answer. TY – Ixar Jul 25 '18 at 15:33

Change Label text in a ContainerView on click of a button from other class (Uiviewcontroller)

1 Answers1