public class MyBroadcastReceiver : BroadcastReceiver() {
  override fun onReceive(context : Context, intent: Intent) {
  
  }
}

BroadcastReceiver myBroadcastReceiver = new MyBroadcastReceiver();
IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
filter.addAction(Intent.ACTION_AIRPLANE_MODE_CHANGED);

// Registration
this.registerReceiver(myBroadcastReceiver, filter);

// Un-registration
unregisterReceiver(myBroadcastReceiver);