SWIFT

create alert in swift

class ViewController: UIViewController {

    @IBAction func showAlertButtonTapped(_ sender: UIButton) {

        // create the alert
        let alert = UIAlertController(title: "My Title", message: "This is my message.", preferredStyle: .alert)

        // add an action (button)
        alert.addAction(UIAlertAction(title: "OK", style: UIAlertAction.Style.default, handler: nil))

        // show the alert
        self.present(alert, animated: true, completion: nil)
    }
}

alert swiftUI

@State private var showingAlert = false

Button("Show Alert") {
            showingAlert = true
        }
        .alert("Important message", isPresented: $showingAlert) {
            Button("OK", role: .cancel) { }
        }