Migrate your GcmListenerService

A custom service for receiving messages (previously based on (GcmListenerService and now on FirebaseMessagingService) is now required only for the following use cases:

• receiving messages with notification payload while the application is in foreground

• receiving messages with data payload only

• receiving errors in case of upstream message failures.

If you don't use these features, and you only care about displaying notifications messages when the app is not in the foreground, you can completely remove this service.

Note: For a list of mandatory migration tasks, see Migrate a GCM Client App for Android to Firebase Cloud Messaging.

Update the Android Manifest

Before

<service
    android:name=".MyGcmListenerService"
    android:exported="false">
    <intent-filter>
        <action android:name="com.google.android.c2dm.intent.RECEIVE" />
    </intent-filter>
</service>

After

<service
    android:name=".MyFcmListenerService">
    <intent-filter>
        <action android:name="com.google.firebase.MESSAGING_EVENT" />
    </intent-filter>
</service>

Update your GcmListenerService

Change MyGcmListenerService.java to extend FirebaseMessagingService and update the signature of the method onMessageReceived(). This example updates the service name to MyFcmListenerService. This is the same class used for token management. If you are also migrating a class extending InstanceIDListenerService these will need to be combined into a single class.

MyGcmListenerService.java Before

public class MyGcmListenerService extends GcmListenerService {
  @Override
  public void onMessageReceived(String from, Bundle data){
    ...
  }

  ...
}

MyFcmListenerService.java After

public class MyFcmListenerService extends FirebaseMessagingService {
  @Override
  public void onMessageReceived(RemoteMessage message){
    String from = message.getFrom();
    Map data = message.getData();
  }
  ...
}