determinePosition method 
    
      
Future<Position>
determinePosition(
)
      
     
    
    
  Implementation
  Future<Position> determinePosition() async {
  bool serviceEnabled;
  LocationPermission permission;
  // Test if location services are enabled.
  serviceEnabled = await Geolocator.isLocationServiceEnabled();
  if (!serviceEnabled) {
    return Future.error('Location services are disabled.');
  }
  permission = await Geolocator.checkPermission();
  if (permission == LocationPermission.denied) {
    permission = await Geolocator.requestPermission();
    if (permission == LocationPermission.denied) {
      return Future.error('Location permissions are denied');
    }
  }
  if (permission == LocationPermission.deniedForever) {
    // Permissions are denied forever, handle appropriately.
    return Future.error(
        'Location permissions are permanently denied, we cannot request permissions.');
  }
  return await Geolocator.getCurrentPosition();
}