How to make an Android status bar notification persist across phone reboot?

This example demonstrate about How to make an Android status bar notification persist across phone reboot

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: tools = "http://schemas.android.com/tools"
   android :layout_width = "match_parent"
   android :layout_height = "match_parent"
   android :padding = "16dp"
   tools :context = ".MainActivity" / >

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

package app.tutorialspoint.com.notifyme ;
import android.os.Bundle ;
import android.support.v7.app.AppCompatActivity ;
public class MainActivity extends AppCompatActivity {
   @Override
   protected void onCreate (Bundle savedInstanceState) {
      super .onCreate(savedInstanceState) ;
      setContentView(R.layout. activity_main ) ;
   }
}

Step 4 − Add the following code to src/USBStateReceiver.

package app.tutorialspoint.com.notifyme ;
import android.annotation. SuppressLint ;
import android.app.Notification ;
import android.app.NotificationChannel ;
import android.app.NotificationManager ;
import android.content.BroadcastReceiver ;
import android.content.Context ;
import android.content.Intent ;
import android.support.v4.app.NotificationCompat ;
import android.util.Log ;
public class USBStateReceiver extends BroadcastReceiver {
   public static final String NOTIFICATION_CHANNEL_ID = "10001" ;
   private final static String default_notification_channel_id = "default" ;
   boolean connected = true;
   @SuppressLint ( "UnsafeProtectedBroadcastReceiver" )
   @Override
   public void onReceive (Context context , Intent intent) {
      NotificationCompat.Builder builder = new NotificationCompat.Builder(context , default_notification_channel_id ) ;
      builder.setContentTitle( "USB - Notification" ) ;
      String action = intent.getAction() ;
      Log. e ( "USB" , action) ;
      assert action != null;
      builder.setContentText( "Connected" ) ;
      builder.setSmallIcon(R.drawable. ic_launcher_foreground ) ;
      builder.setAutoCancel( true ) ;
      builder.setChannelId( NOTIFICATION_CHANNEL_ID ) ;
      Notification notification = builder.build() ;
      NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context. NOTIFICATION_SERVICE ) ;
      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) ;
         assert notificationManager != null;
         notificationManager.createNotificationChannel(notificationChannel) ;
      }
      assert notificationManager != null;
      if ( connected ) {
         notificationManager.notify( 1 , notification) ;
         connected = false;
      } else {
         notificationManager.cancel( 1 ) ;
         connected = true;
   }
}

Step 5 − Add the following code to AndroidManifest.xml

<? xml version= "1.0" encoding= "utf-8" ?>
<manifest xmlns: android = "http://schemas.android.com/apk/res/android"
   package = "app.tutorialspoint.com.notifyme" >
   <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>
      <receiver android :name = ".USBStateReceiver" >
         <intent-filter>
            <action android :name = "android.intent.action.BOOT_COMPLETED" />
         </intent-filter>
      </receiver>
   <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 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