MAUI DisplayAlert() When User Closes Window : Getting Unhandled Exception

Question

I want to show an ALERT/POPUP to the user to ask him/her before he closes the Application.

This is what I am already doing :

In App.xaml.cs

Application.Current.MainPage.DisplayAlert this line throws unhandled exception,
The Exception gets unhandled by debugger itself. and it says :

a debugger is attached to but not configured to debug this unhandled
exception.

https://github.com/BhangeeF16/MAUI-DOT-NET/blob/main/SampleApp/App.xaml.cs

    public partial class App : Application  
    {  
    	public static IServiceProvider Services;  
      
        public App(IServiceProvider serviceProvider)  
        {  
            InitializeComponent();  
            Services = serviceProvider;  
            MainPage = new MainPage();  
        }  
        protected override Window CreateWindow(IActivationState activationState)  
        {  
            Window window = base.CreateWindow(activationState);  
            window.Page = MainPage;  
            window.Destroying += Window_Destroying;  
            return window;  
        }  
      
        private void Window_Destroying(object sender, EventArgs e)  
        {  
            try  
            {  
                System.Diagnostics.Debug.WriteLine("Destroying");  
                App.Current.Dispatcher.Dispatch(async () =>  
                await App.Current.MainPage.DisplayAlert("Alert", "Are you sure you want to close the application.", "Yes", "No"));      
            }  
            catch (Exception)  
            {  
            }  
        }  
    }  
  

Answer 1

It does not make sense to pop up an alert from a destroyed window, the handle will not be valid. The destroy event is for releasing resources.