Интеграция Android приложения с Firebase Cloud Messaging

<service>

            android:name="com.gidbet.dice.MyFirebaseMessagingService"

            android:exported="false">

            <intent-filter>

                <action android:name="com.google.firebase.MESSAGING_EVENT" />

            </intent-filter>

        </service>

public class MyFirebaseMessagingService extends FirebaseMessagingService {

@Override

public void onMessageReceived(RemoteMessage remoteMessage) {

    // ...

    // TODO(developer): Handle FCM messages here.

    // Not getting messages here? See why this may be: https://goo.gl/39bRNJ

    System.out.println("From: " + remoteMessage.getFrom());

    // Check if message contains a notification payload.

    if (remoteMessage.getNotification() != null) {

        System.out.println("Message Notification Body: " + remoteMessage.getNotification().getBody());

    }

    // Also if you intend on generating your own notifications as a result of a received FCM

    // message, here is where that should be initiated. See sendNotification method below.

    sendNotification(remoteMessage.getFrom(), remoteMessage.getNotification().getBody());

    sendNotification(remoteMessage.getNotification().getBody());

}

private void sendNotification(String from, String body) {

    new Handler(Looper.getMainLooper()).post(new Runnable() {

        @Override

        public void run() {

            Toast.makeText(MyFirebaseMessagingService.this.getApplicationContext(), from + " -> " + body,Toast.LENGTH_SHORT).show();

        }

    });

}

private void sendNotification(String messageBody) {

    Intent intent = new Intent(this, MainActivity.class);

    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,

            PendingIntent.FLAG_ONE_SHOT);

    String channelId = "My channel ID";

    Uri defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);

    NotificationCompat.Builder notificationBuilder =

            new NotificationCompat.Builder(this, channelId)

                    .setSmallIcon(R.drawable.ic_launcher_background)

                    .setContentTitle("My new notification")

                    .setContentText(messageBody)

                    .setAutoCancel(true)

                    .setSound(defaultSoundUri)

                    .setContentIntent(pendingIntent);

    NotificationManager notificationManager =

            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

    // Since android Oreo notification channel is needed.

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {

        NotificationChannel channel = new NotificationChannel(channelId,

                "Channel human readable title",

                NotificationManager.IMPORTANCE_DEFAULT);

        notificationManager.createNotificationChannel(channel);

    }

    notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());

}

}.