How to add extended splash to windows template studio?

I'm using windows template studio to create my app, and want to add a extended splash screen refered Display a splash screen for more time.

For the code write in App.xaml.cs in windows template studio, they use ActivationService. I don't know how to add the extended splash properly.

Is any one can help?

How to add extended splash to windows template studio?

You could try to edit ActivationService like the follow

public async Task ActivateAsync(object activationArgs)
{
    if (IsInteractive(activationArgs))
    {
        // Initialize things like registering background task before the app is loaded
        await InitializeAsync();

        if ((activationArgs as LaunchActivatedEventArgs).PreviousExecutionState != ApplicationExecutionState.Running)
        {
            bool loadState = ((activationArgs as LaunchActivatedEventArgs).PreviousExecutionState == ApplicationExecutionState.Terminated);
            ExtendedSplash extendedSplash = new ExtendedSplash((activationArgs as LaunchActivatedEventArgs).SplashScreen, loadState);
            var rootFrame = new Frame();
            rootFrame.Content = extendedSplash;
            Window.Current.Content = rootFrame;
        }

        // Do not repeat app initialization when the Window already has content,
        // just ensure that the window is active
        if (Window.Current.Content == null)
        {
            // Create a Frame to act as the navigation context and navigate to the first page
            Window.Current.Content = _shell?.Value ?? new Frame();
        }
    }

    await HandleActivationAsync(activationArgs);
    _lastActivationArgs = activationArgs;


    if (IsInteractive(activationArgs))
    {
        // Ensure the current window is active
        Window.Current.Activate();

        // Tasks after activation
        await StartupAsync();
    }
}

ExtendedSplash

void DismissExtendedSplash()
{
    // Navigate to mainpage
    rootFrame.Navigate(typeof(ShellPage));
    // Place the frame in the current Window
    Window.Current.Content = rootFrame;
}