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Build your first .NET MAUI app for Windows

Get hands-on with .NET MAUI by building your first cross-platform app on Windows.

Introduction

In this tutorial, you'll learn how to create and run your first .NET MAUI app for Windows in Visual Studio 2022 (17.3 or later). We will add some MVVM Toolkit features from the .NET Community Toolkit to improve the design the default project.

Setting up the environment

If you haven't already set up your environment for .NET MAUI development, please follow the steps to Get started with .NET MAUI on Windows.

Creating the .NET MAUI project

  1. Launch Visual Studio, and in the start window click Create a new project to create a new project:

Create a new project.

  1. In the Create a new project window, select MAUI in the All project types drop-down, select the .NET MAUI App template, and click the Next button:

.NET MAUI App template.

  1. In the Configure your new project window, give your project a name, choose a location for it, and click the Next button:

Name the new project.

  1. In the Additional information window, click the Create button:

Create new project.

  1. Wait for the project to be created, and for its dependencies to be restored:

Project is created.

  1. In the Visual Studio toolbar, press the Windows Machine button to build and run the app.

  2. In the running app, press the Click me button several times and observe that the count of the number of button clicks is incremented:

Run a MAUI app for the first time.

You just ran your first .NET MAUI app on Windows. In the next section, you'll learn how to add data binding and messaging features from the MVVM Toolkit to your app.

Troubleshooting

If your app fails to compile, review Troubleshooting known issues, which may have a solution to your problem.

Adding the MVVM Toolkit

Now that you have your first .NET MAUI app running on Windows, let's add some MVVM Toolkit features to the project to improve the app's design.

  1. Right-click the project in Solution Explorer and select Manage NuGet Packages... from the context menu.

  2. In the NuGet Package Manager window, select the Browse tab and search for CommunityToolkit.MVVM:

CommunityToolkit.MVVM package.

  1. Add the latest stable version of the CommunityToolkit.MVVM package (version 8.0.0 or later) to the project by clicking Install.

  2. Close the NuGet Package Manager window after the new package has finished installing.

  3. Right-click the project again and select Add | Class from the context menu.

  4. In the Add New Item window that appears, name the class MainViewModel and click Add:

Add MainViewModel class.

  1. The MainViewModel class will be the data binding target for the MainPage. Update it to inherit from ObservableObject in the CommunityToolkit.Mvvm.ComponentModel namespace This will also require updating the class to be public and partial.

  2. The MainViewModel class will contain the following code. The CountChangedMessage record defines a message that is sent each time the Click me button is clicked, notifying the view of the change. The ObservableProperty and RelayCommand attributes added to the message and IncrementCounter members are source generators provided by the MVVM Toolkit to create the MVVM boilerplate code for INotifyPropertyChanged and IRelayCommand implementations. The IncrementCounter method's implementation contains the logic from OnCounterClicked in MainPage.xaml.cs, with a change to send a message with the new counter message. We will be removing that code-behind code later.

using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using CommunityToolkit.Mvvm.Messaging;

namespace MauiOnWindows
{
    public sealed record CountChangedMessage(string Text);

    public partial class MainViewModel : ObservableObject
    {
        [ObservableProperty]
        private string message = "Click me";

        private int count;

        [RelayCommand]
        private void IncrementCounter()
        {
            count++;

            if (count == 1)
                message = $"Clicked {count} time";
            else
                message = $"Clicked {count} times";

            WeakReferenceMessenger.Default.Send(new CountChangedMessage(message));
        }
    }
}

Note

You will need to update the namespace in the previous code to match the namespace in your project.

  1. Open the MainPage.xaml.cs file for editing and remove the OnCounterClicked method and the count field.

  2. Add the following code to the MainPage constructor after the call to InitializeComponenent(). This code will receive the message sent by IncrementCounter() in the MainViewModel and will update the CounterBtn.Text property with the new message and announce the new text with the SemanticScreenReader:

WeakReferenceMessenger.Default.Register<CountChangedMessage>(this, (r, m) =>
{
    CounterBtn.Text = m.Text;
    SemanticScreenReader.Announce(m.Text);
});
  1. You will also need to add a using statement to the class:
using CommunityToolkit.Mvvm.Messaging;
  1. In MainPage.xaml, add a namespace declaration to the ContentPage so the MainViewModel class can be found:
xmlns:local="clr-namespace:MauiOnWindows"
  1. Add MainViewModel as the BindingContext for the ContentPage:
<ContentPage.BindingContext>
    <local:MainViewModel/>
</ContentPage.BindingContext>
  1. Update the Button on MainPage to use a Command instead of handling the Clicked event. The command will bind to the IncrementCounterCommand public property that is generated by the MVVM Toolkit's source generators:
<Button
    x:Name="CounterBtn"
    Text="Click me"
    SemanticProperties.Hint="Counts the number of times you click"
    Command="{Binding Path=IncrementCounterCommand}"
    HorizontalOptions="Center" />
  1. Run the project again and observe that the counter is still incremented when you click the button:

Click me button clicked three times.

  1. While the project is running, try updating the "Hello, World!" message in the first Label to read "Hello, Windows!" in MainPage.xaml. Save the file and notice that XAML Hot Reload updates the UI while the app is still running:

Hello World updated to Hello Windows with XAML Hot Reload.

Next steps

Learn to build an app that displays Microsoft Graph data for a user by leveraging the Graph SDK in a .NET MAUI for Windows tutorial.

Resources for learning .NET MAUI

Using the Microsoft Graph API with .NET MAUI on Windows