Permanently running notification listener

Question

I'm trying to write an app that will permanently listen to any incoming notification and then process them. I'm struggling at the first hurdle of making a notification listener that can run permanently even when the app is in the background. Any advice on where to start would be much appreciated?

Thanks

Answer 1

You should be using a service to achieve this.

A service that receives calls from the system when new notifications are posted or removed or their ranking changed.

You should have an android service class which implements NotificationListener()

class NotificationListenerService: NotificationListener() {
   override fun onBind(intent: Intent) {
      return super.onBind(intent)
   }

   override fun onNotificationPosted(sbn: StatusBarNotification) {
      // Implement what you want here
   }

   override fun onNotificationRemoved(sbn: StatusBarNotification) {
      // Implement what you want here
   }
}

Another required thing to do is to have it in your manifest file:

<service android:name=".NotificationListener"
      android:label="@string/service_name"
      android:permission="android.permission.BIND_NOTIFICATION_LISTENER_SERVICE">
 <intent-filter>
     <action android:name="android.service.notification.NotificationListenerService" />
 </intent-filter>

Hope it helps!

Refer for more details: https://developer.android.com/reference/android/service/notification/NotificationListenerService