.NET MAUI Loader logic

AppLoader.cs

using App.Resources.Languages;
using Mopups.Services;

namespace App.Features.Loader;

public class AppLoader : IAsyncDisposable
{
	readonly LoadingPopup _defaultLoadingPopup = new();
	readonly string _defaultLoadingText = AppResources.LblLoading;

	public static async Task<AppLoader> CreateAsync()
	{
		AppLoader myClass = new();
		await myClass.ShowLoader();

		return myClass;
	}

	public static async Task<AppLoader> CreateAsync(string loadingText)
	{
		AppLoader myClass = new();
		await myClass.ShowLoader(loadingText);

		return myClass;
	}

	public async Task ShowLoader(string? loadingText = null)
	{
		try
		{
			_defaultLoadingPopup.UpdateText(loadingText ?? _defaultLoadingText);
			await MopupService.Instance.PushAsync(_defaultLoadingPopup);
		}
		catch(Exception)
		{
			//! Important - Loading pop up is already open. Hide and reshow the loader.
			// This mainly happens on page navigation.
			// i.e. Loader is open on the previous page and is not closed in time before the OnAppearing method is triggered on the next page

			await HideLoader();

			await ShowLoader(loadingText);
		}
	}

	public async Task HideLoader()
	{
		try
		{
			await MopupService.Instance.RemovePageAsync(_defaultLoadingPopup);
		}
		catch(Exception)
		{
			//! Important - thrown if loading pop up has already been removed
		}
	}

	public void UpdateText(string loadingText)
	{
		_defaultLoadingPopup.UpdateText(loadingText);
	}

	bool _disposed; // to detect redundant calls

	public async ValueTask DisposeAsync()
	{
		await DisposeAsyncCore();
		GC.SuppressFinalize(this);
	}

	protected virtual async ValueTask DisposeAsyncCore()
	{
		if(!_disposed)
		{
			await HideLoader();
			_disposed = true;
		}
	}
}

HowToUseIt.cs

async void LoaderExample_Clicked(object sender, EventArgs e)
{
	await using AppLoader loader = await AppLoader.CreateAsync();

	await Task.Delay(2000);
}

LoadingPopup.xaml

<?xml version="1.0" encoding="utf-8" ?>
<Mopups:PopupPage x:Class="App.Features.Loader.LoadingPopup"
                  xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
                  xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
                  xmlns:Animation="clr-namespace:Mopups.Animations;assembly=Mopups"
                  xmlns:Mopups="clr-namespace:Mopups.Pages;assembly=Mopups">
    <Mopups:PopupPage.Animation>
        <Animation:ScaleAnimation DurationIn="500"
                                  PositionIn="Center"
                                  PositionOut="Right"
                                  ScaleIn="1"
                                  ScaleOut="0" />
    </Mopups:PopupPage.Animation>
    <Border Margin="20,20"
            Padding="20"
            BackgroundColor="{DynamicResource BackgroundGradientEndColor}"
            HorizontalOptions="Center"
            VerticalOptions="Center">
        <Border.StrokeShape>
            <RoundRectangle CornerRadius="10" />
        </Border.StrokeShape>
        <VerticalStackLayout Spacing="10">
            <ActivityIndicator x:Name="Spinner"
                               AutomationProperties.ExcludedWithChildren="True"
                               AutomationProperties.IsInAccessibleTree="False"
                               BackgroundColor="Transparent"
                               IsRunning="true"
                               Color="{DynamicResource AccentColour}" />
            <Label x:Name="LoadingLbl"
                   Margin="0"
                   FontAttributes="Bold"
                   FontFamily="InterRegular"
                   HorizontalTextAlignment="Center"
                   Loaded="LoadingLbl_Loaded"
                   TextColor="{DynamicResource TextPrimaryColour}"
                   VerticalTextAlignment="Center" />
        </VerticalStackLayout>
    </Border>
</Mopups:PopupPage>

LoadingPopup.xaml.cs

using App.Extensions;
using App.Resources.Languages;
using Mopups.Pages;

namespace App.Features.Loader;

public partial class LoadingPopup : PopupPage
{
	public LoadingPopup(string? loadingText = null)
	{
		InitializeComponent();
		BackgroundColor = Color.FromArgb("#80000000");

		LoadingLbl.Text = loadingText;

		if(loadingText is not null)
		{
			SemanticProperties.SetDescription(LoadingLbl, loadingText.Equals(AppResources.LblLoading) ? AppResources.LblLoadingAccessibility : loadingText);
		}
	}

	protected override bool OnBackButtonPressed()
	{
		return true;
	}

	protected override bool OnBackgroundClicked()
	{
		return false;
	}

	public void UpdateText(string loadingText)
	{
		LoadingLbl.Text = loadingText;
		SemanticProperties.SetDescription(LoadingLbl, loadingText.Equals(AppResources.LblLoading) ? AppResources.LblLoadingAccessibility : loadingText);

		try
		{
			LoadingLbl.TrySetSemanticFocusForcefully();
		}
		catch(Exception)
		{
			// Intentionally left empty
		}
	}

	void LoadingLbl_Loaded(object sender, EventArgs e)
	{
		if(sender is Label label)
		{
			label.TrySetSemanticFocusForcefully();
		}
	}
}