Cannot present UIAlertController in swift

Question

I've this function

func showMessageNew(msg:String,title: String){
        let alertController = UIAlertController(title: title, message: msg, preferredStyle: .alert)
        let okAction = UIAlertAction(title: "OK", style: .default)
        alertController.addAction(okAction)
        self.present(alertController, animated: true)
}

But when I run it I've this in the console: whose view is not in the window hierarchy!

Answer 1

Below code can be used to present the UIAlertController,

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
            self.showMessageNew(msg: "hi", title: "hi")
            }
        }

    func showMessageNew(msg:String,title: String){
        let alertController = UIAlertController(title: title, message: msg, preferredStyle: .alert)
        let okAction = UIAlertAction(title: "OK", style: .default)
        alertController.addAction(okAction)
        self.present(alertController, animated: true)
    }
}