Android Push Notification Example Java

1/ First Create an Empty Project: Firebase Push Notification

2/ Open Firebase window from Tool Window: Tools -> Firebase

3/ From the Firebase window click the cloud messaging option. You can see two options click on the set up the firebase cloud messaging [ Java ]

After clicking on the link you will see this page 

4/ Click on Connect Firebase

  when you click on the Connect Firebase link you will be redirected to your default browser in the Firebase console

 4.1/ Click on Create a project then Firebase will auto-suggest a name for you and then Click on Continue

 4.2/ You will see another window click on Continue

 4.3/In The next window you need to select Default account for Firebase and click on Create Project

  4.4/ After that your project will create and wait for some time after completing the project click on Continue

4.5/ Then you will be redirected to your project and you will see another window for connecting to your app with Firebase Click on Connect

4.6/ Now you will see the message that the Firebase is connected with the Android app

Close this window and again open your project.

5/ Then add FCM to your app and click on accept changes

6/ Create a new Java class:  FirebasePushNotificationServices

package com.example.fireabasepushnotification;

import android.content.pm.PackageManager;

import androidx.annotation.NonNull;
import androidx.core.app.ActivityCompat;
import androidx.core.app.NotificationCompat;
import androidx.core.app.NotificationManagerCompat;

import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;

public class FirebasePushNotificationServices extends FirebaseMessagingService {
    @Override
    public void onMessageReceived(@NonNull RemoteMessage message) {
        super.onMessageReceived(message);

        NotificationCompat.Builder builder = new NotificationCompat.Builder(this, "fcm_notification")
                .setSmallIcon(R.drawable.notification_icon)
                .setContentTitle(message.getNotification().getTitle())
                .setContentText(message.getNotification().getBody())
                .setAutoCancel(true);

        NotificationManagerCompat notificationManagerCompat = NotificationManagerCompat.from(this);
        if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.POST_NOTIFICATIONS) != PackageManager.PERMISSION_GRANTED) {
            // TODO: Consider calling
            //    ActivityCompat#requestPermissions
            // here to request the missing permissions, and then overriding
            //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
            //                                          int[] grantResults)
            // to handle the case where the user grants the permission. See the documentation
            // for ActivityCompat#requestPermissions for more details.
            return;
        }
        notificationManagerCompat.notify(111, builder.build());
    }
}

7/ Modify Your AndroidManifest.xml

   Add Internet and post notification permission and register the Service (FirebasePushNotificationServices)

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools">

    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>


    <application
        android:allowBackup="true"
        android:dataExtractionRules="@xml/data_extraction_rules"
        android:fullBackupContent="@xml/backup_rules"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.FirebasePushNotification"
        tools:targetApi="31">
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

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

    </application>

</manifest>

8/ Now you can send notifications from firebase to your app

  8.1/ First open your Firebase project and click on Messaging form Run option 

Then click on Create your first campaign

  8.2/ Then Select Firebase Notification Message

8.3/ Create a notification 
     1. Set Notification Title 

    2. Set Notification Text 

   3. Set Notification Image (this is optional )

   after that click on Next

8.4 / Select Target: From the Target option select your app from the dropdown 

And then Click on Review then click on Publish

Run your app

** Note Your phone or emulator must have permission for notifications for your apps
you can check this -> open app info and here you can see  if permission is denied then give the permission