I/flutter ( 6959): │ ⛔ MissingPluginException(No implementation found for method start on channel com.myappp.name/methods)

[narzullayev0772]

@pragma('vm:entry-point')
Future<void> geofenceTriggered(GeofenceCallbackParams params) async {
  const MethodChannel channel = MethodChannel('com.myappp.name/methods');
  try {
    debugPrint('Geofence triggered with params: $params');
// i have tried with this it returned error
    if (params.event == GeofenceEvent.enter) {
      await channel.invokeMethod('start');
    } else {
      await channel.invokeMethod('stop');
    }

// 2. i have tried this it works
// but it works when app is active
    final sendPort = IsolateNameServer.lookupPortByName(AppConstants.kGeofenceIsolateName);
    if (sendPort != null) {
      sendPort.send([params.event.name, params.geofences.first.id]);
    }
  } catch (e, s) {
    LogService.e('Error on geofenceTriggered  $s $e');
  }
}

returned error:
I/flutter ( 6959): │ ⛔ MissingPluginException(No implementation found for method startTracking on channel com.myappp.name/methods)

Problem:
when geofence triggering (enter,exit) i should call channel methods. but it doesnt work. what can i do?

[orkun1675]

It sounds like you are trying to use Flutter plugins in an isolate.

This is unfortunately a Flutter limitation, the plugins are not registered in spawned isolates; and the geofence trigger is running in an insolate.

For a 1P workaround see this. Unfortunately, I don't think there is a way to obtain the RootIsolateToken when the app isn't active.

Another option might be to look into https://pub.dev/packages/flutter_isolate. This might require some code changes in this repo and I'm happy to review PRs if you're willing to contribute.

---

In any case, this is an interesting use case. IIUC you are trying to start geolocator to fetch GPS location in response to a geofence trigger. I'd be interested to know how you get this to work. Please keep us updated.

PS: The promoteToForeground method should come in handy since IIRC Android doesn't allow fetching user location without a foreground service.

[narzullayev0772]

i've already wroted my location tracking plagin in native side. it works when user tap start or stop button (at this time app is active so it works i think). And next i need automatic tracking, it means when user entered to region should start my service, when exit should stop my service.

If you have any suggestion at this situatuion, for example " in native side, you can listen this plugin events " please explain to me

Thanks for reply