How to display count of notifications in Android App?

This example demonstrates how How to display the count of notifications in Android App launcher.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:app="http://schemas.android.com/apk/res-auto"
   xmlns:tools="http://schemas.android.com/tools"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding = "16dp"
   tools:context=".MainActivity">
   <Button
      android:onClick = "createNotification"
      android:text = "create notification"
      android:layout_centerInParent = "true"
      android:layout_width = "match_parent"
      android:layout_height = "wrap_content" />
</RelativeLayout>

Step 3 − Add the following code to src/MainActivity.java

package com.app.sample;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.NotificationCompat;
import android.annotation.SuppressLint;
import android.os.Bundle;
import android.app.NotificationChannel ;
import android.app.NotificationManager ;
import android.app.PendingIntent ;
import android.content.Intent ;
import android.os.Bundle ;
import android.view.View ;
import static android.app.Notification. BADGE_ICON_SMALL ;
public class MainActivity extends AppCompatActivity {
   static int count = 0 ;
   public static final String NOTIFICATION_CHANNEL_ID = "10001" ;
   private final static String default_notification_channel_id = "default" ;
   @Override
   protected void onResume () {
      super .onResume() ;
      count = 0 ;
   }
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
   }
   @SuppressLint("WrongConstant")
      public void createNotification (View view) {
      count ++ ;
      Intent notificationIntent = new Intent(getApplicationContext() , MainActivity.class ) ;
      notificationIntent.putExtra( "fromNotification" , true ) ;
      notificationIntent.setFlags(Intent. FLAG_ACTIVITY_CLEAR_TOP | Intent. FLAG_ACTIVITY_SINGLE_TOP ) ;
      PendingIntent pendingIntent = PendingIntent. getActivity ( this, 0 , notificationIntent , 0 ) ;
      NotificationManager mNotificationManager = (NotificationManager) getSystemService( NOTIFICATION_SERVICE ) ;
      NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getApplicationContext() , default_notification_channel_id ) ;
      mBuilder.setContentTitle( "My Notification" ) ;
      mBuilder.setContentIntent(pendingIntent) ;
      mBuilder.setContentText( "Notification Listener Service Example" ) ;
      mBuilder.setSmallIcon(R.drawable. ic_launcher_foreground ) ;
      mBuilder.setAutoCancel( true ) ;
      mBuilder.setBadgeIconType( BADGE_ICON_SMALL ) ;
      mBuilder.setNumber( count ) ;
      if (android.os.Build.VERSION. SDK_INT >= android.os.Build.VERSION_CODES. O ) {
         int importance = NotificationManager. IMPORTANCE_HIGH ;
         NotificationChannel notificationChannel = new NotificationChannel( NOTIFICATION_CHANNEL_ID , "NOTIFICATION_CHANNEL_NAME" , importance) ;
         mBuilder.setChannelId( NOTIFICATION_CHANNEL_ID ) ;
         assert mNotificationManager != null;
         mNotificationManager.createNotificationChannel(notificationChannel) ;
      }
      assert mNotificationManager != null;
      mNotificationManager.notify(( int ) System. currentTimeMillis () ,
      mBuilder.build()) ;
   }
}

Step 4 − Add the following code to Manifests/AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   package="com.app.sample">
   <uses-permission
      android:name="android.permission.VIBRATE" />
   <uses-permission
      android:name = "android.permission.RECEIVE_BOOT_COMPLETED" />
   <application android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:roundIcon="@mipmap/ic_launcher_round"
      android:supportsRtl="true"
      android:theme="@style/AppTheme">
      <activity android:name=".MainActivity">
         <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
   </application>
</manifest>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from the android studio, open one of your project's activity files and click Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −

Click here to download the project code.