Plugin.Firebase.CloudMessaging 3.1.0

Cloud Messaging

Firebase Cloud Messaging offers a broad range of messaging options and capabilities. I invite you to read the following documentation to have a better understanding about notification messages and data messages and what you can do with them using FCM's options.

Installation

Nuget

Install-Package Plugin.Firebase.CloudMessaging

Setup

• Follow the instructions for the basic setup
• Enable Cloud Messaging at your project in the Firebase Console
• Add the following line of code after calling CrossFirebase.Initialize():

#if IOS
  FirebaseCloudMessagingImplementation.Initialize();
#endif

• Make sure the device is able to receive cloud messages and the user has granted the permissions for it:

  CrossFirebaseCloudMessaging.Current.CheckIfValid()

iOS specifics

• Go to developers.apple.com → Certificates, Identifiers & Profiles → enable Push Notifications in your provisioning profile, download and double tap it
• Create and upload APNs authentication key to your project in the Firebase Console
• Enable Push Notifications in your apps Entitlements.plist:

  <key>aps-environment</key>
  <string>development</string>

• For testing launch the app without the debugger, otherwise the push notification may not be received
• For more specific instructions take a look at the official Firebase documentation

Android specifics

• Add the following code snippet to the <application> tag in your apps AndroidManifest.xml:

  <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>

• Call FirebaseCloudMessagingImplementation.OnNewIntent(intent) from MainActivity.OnCreate(...) and MainActivity.OnNewIntent(...)
• Create a notification channel and set the ChannelId to FirebaseCloudMessagingImplementation:

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

Customize local push notifications

Local push notifications are shown by default in a specific way, but you have the following two options to customize this behavior:

Overriding FirebaseCloudMessagingImplementation.NotificationBuilderProvider:

FirebaseCloudMessagingImplementation.NotificationBuilderProvider = notificaion => new NotificationCompat.Builder(context, channelId)
    .SetSmallIcon(Android.Resource.Drawable.SymDefAppIcon)
    .SetContentTitle(notification.Title)
    .SetContentText(notification.Body)
    .SetPriority(NotificationCompat.PriorityDefault)
    .SetAutoCancel(true);

Setting FirebaseCloudMessagingImplementation.ShowLocalNotificationAction:

FirebaseCloudMessagingImplementation.ShowLocalNotificationAction = notification => {

    var intent = PackageManager.GetLaunchIntentForPackage(PackageName);
    intent.PutExtra(FirebaseCloudMessagingImplementation.IntentKeyFCMNotification, notification.ToBundle());
    intent.SetFlags(ActivityFlags.ClearTop | ActivityFlags.SingleTop);

    var pendingIntent = PendingIntent.GetActivity(context, 0, intent, PendingIntentFlags.Immutable | PendingIntentFlags.UpdateCurrent);
    var builder = new NotificationCompat.Builder(context, channelId)
        .SetSmallIcon(Android.Resource.Drawable.SymDefAppIcon)
        .SetContentTitle(notification.Title)
        .SetContentText(notification.Body)
        .SetPriority(NotificationCompat.PriorityDefault)
        .SetAutoCancel(true);

    var notificationManager = (NotificationManager) GetSystemService(NotificationService);
    notificationManager.Notify(123, builder.SetContentIntent(pendingIntent).Build());
};

You can find more specific instructions for android at the official Firebase documentation

Usage

Take a look at the documentation for the AdamE.Firebase.iOS.CloudMessaging packages, because Plugin.Firebase's code is abstracted but still very similar.

Since code should be documenting itself you can also take a look at the following classes:

• src/.../IFirebaseCloudMessaging.cs
• sample/.../PushNotificationService.cs

Test with curl

curl --location 'https://fcm.googleapis.com/fcm/send' \
--header 'Authorization: key=<your-api-token-from-firebase-console-cloud-messaging-project-settings>' \
--header 'Content-Type: application/json' \
--data '{
 "to" : "<your-device-fcm-token>",
 "collapse_key" : "type_a",
 "mutable_content": true,
 "notification" : {
     "title": "Knock knock",
     "body" : "Who's there?",
     "badge": 1
 },
 "data" : {
     "body" : "body of your notification in data",
     "title": "title of your notification in data",
     "is_silent_in_foreground": "false"
 }
}'

Extra flags

is_silent_in_foreground

Add "is_silent_in_foreground": "true" to the data payload to prevent showing the local push notification. The flag prevents a notification to be generated if the app is in foreground - otherwise the notifications will still be shown. Event CrossFirebaseCloudMessaging.Current.NotificationReceived is still triggered to allow for manual notification handling.

Note: this is a Plugin.Firebase custom field and hence not documented with google FCM documentation.

Troubleshooting

If you are having trouble receiving push notifications on your device, take a look at this helpful https://github.com/TobiasBuchholz/Plugin.Firebase/issues/145#issuecomment-1455182588 by @andyzukunft. Additionally he has created a dedicated project to simplify the demonstration on how Firebase Cloud Messaging works: https://github.com/andyzukunft/Plugin.Firebase/tree/fcm-demo/sample/Fcm

Release notes

• Version 3.0.0
  • Swapped Xamarin.Firebase.iOS.CloudMessaging (native SDK 8.10.0) for AdamE.Firebase.iOS.CloudMessaging (native SDK 10.24.0)
• Version 2.0.4
  • Add FirebaseCloudMessagingImplementation.ShowLocalNotificationAction (issue #163)
• Version 2.0.3
  • Enable silent push notifications when the app is in foreground (PR #188)
• Version 2.0.2
  • Prevent error message when no image is attached to push notifications
• Version 2.0.1
  • Remove unnecessary UseMaui property from csproj files
  • Readd net6.0 tfm