Android notifications

FirebaseMessagingService.java

public class FirebaseMessagingService extends FirebaseMessagingService {

    @Override
    public void onMessageReceived(@NotNull RemoteMessage remoteMessage) {

        // Not getting messages here? See why this may be: https://goo.gl/39bRNJ
        Log.d(ContentValues.TAG, "From: " + remoteMessage.getFrom());

        // Check if message contains a data payload.
        if (!remoteMessage.getData().isEmpty()) {
            Log.d(ContentValues.TAG, "Message data payload: " + remoteMessage.getData());
        }

        // Check if message contains a notification payload.
        if (remoteMessage.getNotification() != null) {
            Log.d(ContentValues.TAG, "Message Notification Body: " + remoteMessage.getNotification().getBody());
        }

    }

    @Override
    public void onNewToken(@NotNull String token) {
        Log.d(ContentValues.TAG, "Refreshed token: $token");
    }
}

FirebaseMessagingService.kt

class FirebaseMessagingService : FirebaseMessagingService() {

    override fun onMessageReceived(remoteMessage: RemoteMessage) {

        // Not getting messages here? See why this may be: https://goo.gl/39bRNJ
        Log.d(ContentValues.TAG, "From: " + remoteMessage.from!!)

        // Check if message contains a data payload.
        if (remoteMessage.data.isNotEmpty()) {
            Log.d(ContentValues.TAG, "Message data payload: " + remoteMessage.data)
        }

        // Check if message contains a notification payload.
        if (remoteMessage.notification != null) {
            Log.d(ContentValues.TAG, "Message Notification Body: " + remoteMessage.notification!!.body!!)
        }
    }

    override fun onNewToken(token: String) {
        Log.d(ContentValues.TAG, "Refreshed token: $token")
    }

}

MainActivity.java

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        // Subscribe
        FirebaseMessaging.getInstance().subscribeToTopic("VisionNews")
                .addOnCompleteListener(new OnCompleteListener<Void>() {
                    @Override
                    public void onComplete(@NonNull Task<Void> task) {
                        String msg = getString(R.string.msg_subscribed);

                        if (!task.isSuccessful()) {
                            msg = getString(R.string.msg_subscribe_failed);
                        }

                        Log.d(ContentValues.TAG, msg);
                        Toast.makeText(getBaseContext(), msg, Toast.LENGTH_SHORT).show();
                    }
                });


        // Get firebase token
        FirebaseInstanceId.getInstance().getInstanceId().addOnCompleteListener(new OnCompleteListener<InstanceIdResult>() {
            @Override
            public void onComplete(@NonNull Task<InstanceIdResult> task) {
                if (!task.isSuccessful()) {
                    Log.w(ContentValues.TAG, "getInstanceId failed", task.getException());
                }

                // Get new Instance ID token
                String token = task.getResult().getToken();

                // Log and toast
                String msg = getString(R.string.msg_token_fmt, token);
                Log.d(ContentValues.TAG, msg);
                Toast.makeText(getBaseContext(), msg, Toast.LENGTH_SHORT).show();
            }
        });
    }
}

MainActivity.kt

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // Subscribe
        FirebaseMessaging.getInstance().subscribeToTopic("VisionNews")
            .addOnCompleteListener { task ->
                var msg = getString(R.string.msg_subscribed)
                if (!task.isSuccessful) {
                    msg = getString(R.string.msg_subscribe_failed)
                }
                Log.d(ContentValues.TAG, msg)
                Toast.makeText(baseContext, msg, Toast.LENGTH_SHORT).show()
            }

        // Get firebase token
        FirebaseInstanceId.getInstance().instanceId
            .addOnCompleteListener{ task ->
                if (!task.isSuccessful) {
                    Log.w(ContentValues.TAG, "getInstanceId failed", task.exception)
                }

                // Get new Instance ID token
                val token = task.result?.token

                // Log and toast
                val msg = getString(R.string.msg_token_fmt, token)
                Log.d(ContentValues.TAG, msg)
                Toast.makeText(baseContext, msg, Toast.LENGTH_SHORT).show()
            }
    }
}