Firebase Push Notifications don't work when migrating my Xamarin app to .NET MAUI

[pedro-rodrigues18]

I need help to make push notifications via firebase work. I'm migrating an app from Xamarin to .NET MAUI and the notifications aren't arriving. I'm using Plugin.Firebase.

I am running the app using my Samsung S20FE smartphone with Android 13.

Does anyone have an idea of ​​what might be happening for notifications not arriving?

Note: I followed the tutorial: Firebase Push Notifications in .NET MAUI (Android)

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="br.com.testnotification" android:versionCode="2" android:versionName="2.2">
	<application android:allowBackup="true" android:icon="@mipmap/appicon" android:supportsRtl="true" android:label="He2Solar">
		<receiver
			android:name="com.google.firebase.iid.FirebaseInstanceIdInternalReceiver"
			android:exported="false" />
		<receiver
			android:name="com.google.firebase.iid.FirebaseInstanceIdReceiver"
			android:exported="true"
			android:permission="com.google.android.c2dm.permission.SEND">
			<intent-filter>
				<action android:name="com.google.android.c2dm.intent.RECEIVE" />
				<action android:name="com.google.android.c2dm.intent.REGISTRATION" />
				<category android:name="${applicationId}" />
			</intent-filter>
		</receiver>
	</application>
	<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
	<uses-permission android:name="android.permission.INTERNET" />
	<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
	<uses-permission android:name="android.permission.VIBRATE" />
	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
	<uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
</manifest>

MainActivity.cs

using Android.App;
using Android.Content;
using Android.Content.PM;
using Android.OS;
using AndroidX.Core.App;
using AndroidX.Core.Content;
using Plugin.Firebase.CloudMessaging;

namespace gdgestaomobile
{
    [Activity(Theme = "@style/Maui.SplashTheme", MainLauncher = true, LaunchMode = LaunchMode.SingleTop, ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation | ConfigChanges.UiMode | ConfigChanges.ScreenLayout | ConfigChanges.SmallestScreenSize | ConfigChanges.Density, ScreenOrientation = ScreenOrientation.Portrait)]
    public class MainActivity : MauiAppCompatActivity
    {
        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);
            HandleIntent(Intent);
            CreateNotificationChannelIfNeeded();
        }

        protected override void OnNewIntent(Intent intent)
        {
            base.OnNewIntent(intent);
            HandleIntent(intent);
        }

        private static void HandleIntent(Intent intent)
        {
            FirebaseCloudMessagingImplementation.OnNewIntent(intent);
        }

        private void CreateNotificationChannelIfNeeded()
        {
            if (Build.VERSION.SdkInt >= BuildVersionCodes.O)
            {
                CreateNotificationChannel();
            }
        }

        private void CreateNotificationChannel()
        {
            var channelId = $"{PackageName}.general";
            var notificationManager = (NotificationManager)GetSystemService(NotificationService);
            var channel = new NotificationChannel(channelId, "General", NotificationImportance.Default);
            notificationManager.CreateNotificationChannel(channel);
            FirebaseCloudMessagingImplementation.ChannelId = channelId;
        }
    }
}

MauiProgram.cs

using Microsoft.Extensions.Logging;
using Microsoft.Maui.LifecycleEvents;
using Plugin.Firebase.Auth;
using Plugin.Firebase.Bundled.Shared;
using Plugin.Firebase.Core.Platforms.Android;
using Plugin.Firebase.Crashlytics;
#if IOS
using Plugin.Firebase.Bundled.Platforms.iOS;
#else
using Plugin.Firebase.Bundled.Platforms.Android;
#endif

namespace gdgestaomobile
{
    public static class MauiProgram
    {
        public static MauiApp CreateMauiApp()
        {
            var builder = MauiApp.CreateBuilder();
            builder
                .UseMauiApp<App>()
                .ConfigureFonts(fonts =>
                {
                    fonts.AddFont("OpenSans-Regular.ttf", "OpenSansRegular");
                    fonts.AddFont("OpenSans-Semibold.ttf", "OpenSansSemibold");
                });

            Microsoft.Maui.Handlers.EntryHandler.Mapper.AppendToMapping(nameof(Entry), (handler, view) =>
            {
#if ANDROID
                handler.PlatformView.SetBackgroundColor(Android.Graphics.Color.Transparent);
#endif
            });

#if DEBUG
            builder.Logging.AddDebug();
#endif

            return builder.Build();
        }
        private static MauiAppBuilder RegisterFirebaseServices(this MauiAppBuilder builder)
        {
            builder.ConfigureLifecycleEvents(events => {
#if IOS
            events.AddiOS(iOS => iOS.FinishedLaunching((app, launchOptions) => {
                CrossFirebase.Initialize(CreateCrossFirebaseSettings());
                return false;
            }));
#else
                events.AddAndroid(android => android.OnCreate((activity, _) =>
                    Plugin.Firebase.Bundled.Platforms.Android.CrossFirebase.Initialize(activity, CreateCrossFirebaseSettings())));
                
                CrossFirebaseCrashlytics.Current.SetCrashlyticsCollectionEnabled(true);
#endif          
            });

            builder.Services.AddSingleton(_ => CrossFirebaseAuth.Current);
            return builder;
        }

        private static CrossFirebaseSettings CreateCrossFirebaseSettings()
        {
            return new CrossFirebaseSettings(
                isAuthEnabled: true,
                isCloudMessagingEnabled: true,
                isAnalyticsEnabled: true
            );
        }
    }
}

gdgestaomobile

<Project Sdk="Microsoft.NET.Sdk">

	<PropertyGroup>
		<TargetFrameworks>;net8.0-android34.0</TargetFrameworks>

		<OutputType>Exe</OutputType>
		<RootNamespace>gdgestaomobile</RootNamespace>
		<UseMaui>true</UseMaui>
		<SingleProject>true</SingleProject>
		<ImplicitUsings>enable</ImplicitUsings>
		<Nullable>enable</Nullable>

		<!-- Display name -->
		<ApplicationTitle>He2Solar</ApplicationTitle>

		<!-- App Identifier -->
		<ApplicationId>br.com.testnotification</ApplicationId>

		<!-- Versions -->
		<ApplicationDisplayVersion>2.2</ApplicationDisplayVersion>
		<ApplicationVersion>2</ApplicationVersion>

		<!--<SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'ios'">11.0</SupportedOSPlatformVersion>-->
		<SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'android'">21.0</SupportedOSPlatformVersion>
		<!--<SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'tizen'">6.5</SupportedOSPlatformVersion>-->
	</PropertyGroup>
	
	<ItemGroup>
		<!-- App Icon -->
		<MauiIcon Include="Resources\AppIcon\appicon.svg" ForegroundFile="Resources\AppIcon\icon.png" Color="#ff8c00" BaseSize="42,42" />

		<!-- Splash Screen -->
		<MauiImage Include="Resources\Splash\splash.svg" />

		<!-- Images -->
		<MauiImage Include="Resources\Images\*" />

		<!-- Custom Fonts -->
		<MauiFont Include="Resources\Fonts\*" />

		<!-- Raw Assets (also remove the "Resources\Raw" prefix) -->
		<MauiAsset Include="Resources\Raw\**" LogicalName="%(RecursiveDir)%(Filename)%(Extension)" />
	</ItemGroup>
	
	<ItemGroup>
		<PackageReference Include="CommunityToolkit.Mvvm" Version="8.2.2" /> 
		<PackageReference Include="Microsoft.Maui.Controls" Version="$(MauiVersion)" />
		<PackageReference Include="Microsoft.Maui.Controls.Compatibility" Version="$(MauiVersion)" />
		<PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="8.0.0" />
		<PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
		<PackageReference Include="sqlite-net-pcl" Version="1.9.172" />
		<PackageReference Include="Plugin.Firebase" Version="3.0.0" />
		<PackageReference Include="Plugin.Firebase.Crashlytics" Version="3.0.0" />
		<PackageReference Include="Xam.Plugin.Connectivity" Version="3.2.0" />
	</ItemGroup>
	
	<ItemGroup>
		<PackageReference Include="Xamarin.AndroidX.Fragment.Ktx" Version="1.6.2" />
		<PackageReference Include="Xamarin.Firebase.Messaging" Version="123.2.1.1" />		
	</ItemGroup>
	
	<ItemGroup>
		<GoogleServicesJson Include="Platforms\Android\google-services.json" />
	</ItemGroup>

	<ItemGroup>
	  <MauiXaml Update="Views\Contas\ContasPage.xaml">
	    <Generator>MSBuild:Compile</Generator>
	  </MauiXaml>
	  <MauiXaml Update="Views\Home\HomePage.xaml">
	    <Generator>MSBuild:Compile</Generator>
	  </MauiXaml>
	  <MauiXaml Update="Views\Home\Instalacoes\InstalacoesPage.xaml">
	    <Generator>MSBuild:Compile</Generator>
	  </MauiXaml>
	  <MauiXaml Update="Views\MainPage.xaml">
	    <Generator>MSBuild:Compile</Generator>
	  </MauiXaml>
	  <MauiXaml Update="Views\Login\LoginPage.xaml">
	    <Generator>MSBuild:Compile</Generator>
	  </MauiXaml>
	  <MauiXaml Update="Views\Notificacoes\NotificacoesPage.xaml">
	    <Generator>MSBuild:Compile</Generator>
	  </MauiXaml>
	  <MauiXaml Update="Views\Perfil\PerfilPage.xaml">
	    <Generator>MSBuild:Compile</Generator>
	  </MauiXaml>
	  <MauiXaml Update="Views\PrincipalPage.xaml">
	    <Generator>MSBuild:Compile</Generator>
	  </MauiXaml>
	</ItemGroup>

	<ItemGroup>
	  <Folder Include="Resources\Images\" />
	</ItemGroup>

	<ItemGroup>
	  <MauiImage Include="Resources\AppIcon\icon.png" />
	  <MauiImage Include="Resources\AppIcon\launcher_foreground.png" />
	  <MauiImage Include="Resources\AppIcon\logo.png" />
	</ItemGroup>

</Project>

[gautambjain]

Please implement what is discussed here: #22998 .

This thing works. I just launched my app yesterday on Google Play Store.