Can I present a toast when alert is also presented?

Question

Do you know if it's possible to present a toast message while alert is presented?

More specific, the alert contains a textfield and I want to present a toast with error message when textfield's value is over Integer's max value. So, when user gives me an incorrect value, I want to inform the user before he/she presses the alert button.

Can you help me?

Answer 1

There is no such a thing as toast in native UIKit components!

So you can either use another Alert on top of the previous one:

class MainViewController: UIViewController {
    @IBOutlet weak var button: UIButton!
    var alert: UIAlertController!

    @IBAction func buttonDidTouch() {
        alert = UIAlertController(title: "Authentication", message: "Choose a username and password", preferredStyle: .alert)

        alert.addTextField { textfield in
            textfield.placeholder = "Username"
            textfield.addTarget(self, action: #selector(self.changeUsername), for: .editingChanged)
        }
        alert.addTextField() { $0.placeholder = "Password" }
        alert.addAction(.init(title: "Register", style: .default))
        present(alert, animated: true)
    }

    @objc func changeUsername(sender: UITextField) {
        let text = sender.text!
        guard text.count > 5 else { return }
        sender.text = String(text.prefix(5))

        let toast = UIAlertController(title: "Invalid username", message: "The username should not be longer than 5 letters", preferredStyle: .alert)
        toast.addAction(.init(title: "Ok", style: .cancel))

        alert.present(toast, animated: true)
    }
}

_{Note: You may want to get rid of all !s and make them safe as you wish}

---

Or create a new window with a level more than the alert like the statusBar (or using libraries like this) and present it on top of the current window to achieve something like this:

Note: window management is a large topic and beyond the scope of this question. I suggest you to start with simple approaches and then go for tough ones. You can start with this:

class MainViewController: UIViewController {
    @IBOutlet weak var button: UIButton!

    lazy var window: UIWindow = {
        let w = UIWindow(windowScene: view.window!.windowScene!)
        w.windowLevel = .statusBar
        w.backgroundColor = .green.withAlphaComponent(0.7)
        return w
    }()

    @IBAction func buttonDidTouch() {
        window.makeKeyAndVisible()
    }
}

Answer 2

In iOS, it's not possible to present a toast message while an alert is being displayed natively using UIKit or SwiftUI. The alert view typically blocks the UI until it is dismissed, preventing the presentation of other UI elements such as toast messages.

However, you can achieve a similar effect by customizing the alert view itself to display the error message directly within the alert. Instead of showing a separate toast message, you can include the error message within the alert's message or use a specific style to highlight the error.