How to do Login with Firebase integration in .NET MAUI?

Question

I'm trying to login with integration to social networks, more specifically to Google in .NET MAUI. I've done it with Xamarin Forms and it worked perfectly, however, in MAUI a standard error is occurring:

Error CS0246 The type or namespace name 'Android' could not be found (are you missing a using directive or an assembly reference?) LoginWithRedes (net6.0-ios), LoginWithRedes (net6.0-maccatalyst), LoginWithRedes (net6.0-windows10.0.19041) C:\MAUI\LoginWithRedes\LoginWithRedes\Platforms\Android\GoogleManager.cs

Libraries not being recognized

Packages I added to the project

Code of the GoogleManager.CS Class where the standard error occurs to me:

`[assembly: Dependency(typeof(GoogleManager))] namespace LoginWithRedes.Platforms.Android { public class GoogleManager : Java.Lang.Object, IGoogleManager, GoogleApiClient.IConnectionCallbacks, GoogleApiClient.IOnConnectionFailedListener { public static GoogleApiClient _googleApiClient { get; set; } public static GoogleManager Instance { get; private set; }

    public bool IsLogedIn { get; set; }

    Context _context;

    public GoogleManager()
    {
        _context = global::Android.App.Application.Context;
        Instance = this;
    }

    public void Login()
    {
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DefaultSignIn)
                                                         .RequestEmail()
                                                         .Build();
        _googleApiClient = new GoogleApiClient.Builder((_context).ApplicationContext)
            .AddConnectionCallbacks(this)
            .AddOnConnectionFailedListener(this)
            .AddApi(Auth.GOOGLE_SIGN_IN_API, gso)
            .AddScope(new Scope(Scopes.Profile))
            .Build();


        Intent signInIntent = Auth.GoogleSignInApi.GetSignInIntent(_googleApiClient);
        ((MainActivity)Forms.Context).StartActivityForResult(signInIntent, 1);
        _googleApiClient.Connect();
    }

    public void Logout()
    {
        var gsoBuilder = new GoogleSignInOptions.Builder(GoogleSignInOptions.DefaultSignIn).RequestEmail();

        GoogleSignIn.GetClient(_context, gsoBuilder.Build())?.SignOut();

        _googleApiClient.Disconnect();

    }

    public void OnAuthCompleted(GoogleSignInResult result)
    {
        if (result.IsSuccess)
        {
            IsLogedIn = true;
            Application.Current.MainPage = new MainPage();

        }
        else
        {



        }
    }`

OnActivityResult method that I implemented in MainActivity class

If anyone can help me with this error, I would be very grateful. Note: I'm new to Xamarin and Maui.

Thank you very much in advance

Answer 1

I'm also new to Maui, and in my experience, these errors were caused by using native Xamarin libraries in Maui. Xamarin targets each platform separately using separate nuget packages. Maui's combined 1-project architecture means you need to use packages that work for both at once.

At least when I was getting started a few months ago, these weren't readily available. Firebase client was not yet released for .NET 6.0 (Multiplatform by default).

Things may have changed since then. But I had great success using Firebase with this plugin https://github.com/TobiasBuchholz/Plugin.Firebase. It wraps up the platform specific libraries into a single project API, with a really easy to use c# interface. You can use await and stuff as you would expect. Calling the native APIs was difficult, and required a lot of code duplication. This plugin saves a lot of time, and I haven't yet run into any problems.

The documentation on the plugin is a bit sparse, but hey, it's free and works.