FCM - MyFirebaseMessagingService.java

MyFirebaseMessagingService.java

package com.example.fcm;

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Color;
import android.media.RingtoneManager;
import android.support.v4.app.NotificationCompat;
import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;
import java.io.IOException;
import java.net.URL;
import java.util.Map;

public class MyFirebaseMessagingService extends FirebaseMessagingService {
	/**
	 * Called when message is received.
	 *
	 * @param remoteMessage Object representing the message received from Firebase Cloud Messaging.
	 */
	@Override
	public void onMessageReceived(RemoteMessage remoteMessage) {
		super.onMessageReceived(remoteMessage);
		// TODO(developer): Handle FCM messages here.
		// If the application is in the foreground handle both data and notification messages here.
		// 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.
		RemoteMessage.Notification notification = remoteMessage.getNotification();
		Map<String, String> data = remoteMessage.getData();

		sendNotification(notification, data);
	}

	/**
	 * Create and show a custom notification containing the received FCM message.
	 *
	 * @param notification FCM notification payload received.
	 * @param data FCM data payload received.
	 */
	private void sendNotification(RemoteMessage.Notification notification, Map<String, String> data) {
		Bitmap icon = BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher);

		Intent intent = new Intent(this, MainActivity.class);
		intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
		PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_ONE_SHOT);

		NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, "channel_id")
				.setContentTitle(notification.getTitle())
				.setContentText(notification.getBody())
				.setAutoCancel(true)
				.setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION))
				.setContentIntent(pendingIntent)
				.setContentInfo(notification.getTitle())
				.setLargeIcon(icon)
				.setColor(Color.RED)
				.setLights(Color.RED, 1000, 300)
				.setDefaults(Notification.DEFAULT_VIBRATE)
				.setSmallIcon(R.mipmap.ic_launcher);

		try {
			String picture_url = data.get("picture_url");
			if (picture_url != null && !"".equals(picture_url)) {
				URL url = new URL(picture_url);
				Bitmap bigPicture = BitmapFactory.decodeStream(url.openConnection().getInputStream());
				notificationBuilder.setStyle(
					new NotificationCompat.BigPictureStyle().bigPicture(bigPicture).setSummaryText(notification.getBody())
				);
			}
		} catch (IOException e) {
			e.printStackTrace();
		}

		NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
		
		// Notification Channel is required for Android O and above
		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
			NotificationChannel channel = new NotificationChannel(
				"channel_id", "channel_name", NotificationManager.IMPORTANCE_DEFAULT
			);
			channel.setDescription("channel description");
			channel.setShowBadge(true);
			channel.canShowBadge();
			channel.enableLights(true);
			channel.setLightColor(Color.RED);
			channel.enableVibration(true);
			channel.setVibrationPattern(new long[]{100, 200, 300, 400, 500});
			notificationManager.createNotificationChannel(channel);
		}
		
		notificationManager.notify(0, notificationBuilder.build());
	}
}

Sorry, as I know you cannot set custom notification sound by programming.

Nice example! Thanks a bunch!