FirebaseInstanceIdService is deprecated

Update 11-12-2020

Now FirebaseInstanceId is also deprectaed

Now we need to use FirebaseMessaging.getInstance().token

SAMPLE CODE

        FirebaseMessaging.getInstance().token.addOnCompleteListener {
            if(it.isComplete){
                firebaseToken = it.result.toString()
                Util.printLog(firebaseToken)
            }
        }

    

Yes FirebaseInstanceIdService is deprecated

FROM DOCS :- This class was deprecated. In favour of overriding onNewToken in FirebaseMessagingService. Once that has been implemented, this service can be safely removed.

No need to use FirebaseInstanceIdService service to get FCM token You can safely remove FirebaseInstanceIdService service

Now we need to @Override onNewToken get Token in FirebaseMessagingService

SAMPLE CODE

public class MyFirebaseMessagingService extends FirebaseMessagingService {

    @Override
    public void onNewToken(String s) {
        Log.e("NEW_TOKEN", s);
    }

    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {

        Map<String, String> params = remoteMessage.getData();
        JSONObject object = new JSONObject(params);
        Log.e("JSON_OBJECT", object.toString());

        String NOTIFICATION_CHANNEL_ID = "Nilesh_channel";

        long pattern[] = {0, 1000, 500, 1000};

        NotificationManager mNotificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            NotificationChannel notificationChannel = new NotificationChannel(NOTIFICATION_CHANNEL_ID, "Your Notifications",
                    NotificationManager.IMPORTANCE_HIGH);

            notificationChannel.setDescription("");
            notificationChannel.enableLights(true);
            notificationChannel.setLightColor(Color.RED);
            notificationChannel.setVibrationPattern(pattern);
            notificationChannel.enableVibration(true);
            mNotificationManager.createNotificationChannel(notificationChannel);
        }

        // to diaplay notification in DND Mode
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            NotificationChannel channel = mNotificationManager.getNotificationChannel(NOTIFICATION_CHANNEL_ID);
            channel.canBypassDnd();
        }

        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID);

        notificationBuilder.setAutoCancel(true)
                .setColor(ContextCompat.getColor(this, R.color.colorAccent))
                .setContentTitle(getString(R.string.app_name))
                .setContentText(remoteMessage.getNotification().getBody())
                .setDefaults(Notification.DEFAULT_ALL)
                .setWhen(System.currentTimeMillis())
                .setSmallIcon(R.drawable.ic_launcher_background)
                .setAutoCancel(true);


        mNotificationManager.notify(1000, notificationBuilder.build());
    }
}

#EDIT

You need to register your FirebaseMessagingService in manifest file like this

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

#how to get token in your activity

.getToken(); is also deprecated if you need to get token in your activity than Use getInstanceId ()

Now we need to use getInstanceId () to generate token

getInstanceId () Returns the ID and automatically generated token for this Firebase project.

This generates an Instance ID if it does not exist yet, which starts periodically sending information to the Firebase backend.

Returns

• Task which you can use to see the result via the InstanceIdResult which holds the ID and token.

SAMPLE CODE

FirebaseInstanceId.getInstance().getInstanceId().addOnSuccessListener( MyActivity.this,  new OnSuccessListener<InstanceIdResult>() {
     @Override
     public void onSuccess(InstanceIdResult instanceIdResult) {
           String newToken = instanceIdResult.getToken();
           Log.e("newToken",newToken);

     }
 });

##EDIT 2

Here is the working code for kotlin

class MyFirebaseMessagingService : FirebaseMessagingService() {

    override fun onNewToken(p0: String?) {

    }

    override fun onMessageReceived(remoteMessage: RemoteMessage?) {


        val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        val NOTIFICATION_CHANNEL_ID = "Nilesh_channel"

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val notificationChannel = NotificationChannel(NOTIFICATION_CHANNEL_ID, "Your Notifications", NotificationManager.IMPORTANCE_HIGH)

            notificationChannel.description = "Description"
            notificationChannel.enableLights(true)
            notificationChannel.lightColor = Color.RED
            notificationChannel.vibrationPattern = longArrayOf(0, 1000, 500, 1000)
            notificationChannel.enableVibration(true)
            notificationManager.createNotificationChannel(notificationChannel)
        }

        // to diaplay notification in DND Mode
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val channel = notificationManager.getNotificationChannel(NOTIFICATION_CHANNEL_ID)
            channel.canBypassDnd()
        }

        val notificationBuilder = NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID)

        notificationBuilder.setAutoCancel(true)
                .setColor(ContextCompat.getColor(this, R.color.colorAccent))
                .setContentTitle(getString(R.string.app_name))
                .setContentText(remoteMessage!!.getNotification()!!.getBody())
                .setDefaults(Notification.DEFAULT_ALL)
                .setWhen(System.currentTimeMillis())
                .setSmallIcon(R.drawable.ic_launcher_background)
                .setAutoCancel(true)


        notificationManager.notify(1000, notificationBuilder.build())

    }
}

firebaser here

Check the reference documentation for FirebaseInstanceIdService:

This class was deprecated.

In favour of overriding onNewToken in FirebaseMessagingService. Once that has been implemented, this service can be safely removed.

Weirdly enough the JavaDoc for FirebaseMessagingService doesn't mention the onNewToken method yet. It looks like not all updated documentation has been published yet. I've filed an internal issue to get the updates to the reference docs published, and to get the samples in the guide updated too.

In the meantime both the old/deprecated calls, and the new ones should work. If you're having trouble with either, post the code and I'll have a look.

Simply call this method to get the Firebase Messaging Token

public void getFirebaseMessagingToken ( ) {
        FirebaseMessaging.getInstance ().getToken ()
                .addOnCompleteListener ( task -> {
                    if (!task.isSuccessful ()) {
                        //Could not get FirebaseMessagingToken
                        return;
                    }
                    if (null != task.getResult ()) {
                        //Got FirebaseMessagingToken
                        String firebaseMessagingToken = Objects.requireNonNull ( task.getResult () );
                        //Use firebaseMessagingToken further
                    }
                } );
    }

The above code works well after adding this dependency in build.gradle file

implementation 'com.google.firebase:firebase-messaging:21.1.0'

Note: This is the code modification done for the above dependency to resolve deprecation. (Working code as of 9th May 2021)