location_service.dart

import 'package:flutter/material.dart';
import 'package:geolocator/geolocator.dart';

class LocationService {
  
  /// BuildContext is used to show alert dialog later.
  BuildContext context;

  LocationService(this.context);

  ///
  /// getCurrentLocation first checks location permissions if enabled,
  /// it requests to get user [currentLocation] and then return it.
  ///
  getCurrentLocation() async {
    Position currentLocation =
        await getCurrentPosition(desiredAccuracy: LocationAccuracy.high);
    if(currentLocation == null){
      await checkPermissionStatus();
      await checkGpsService();
      currentLocation =
        await getCurrentPosition(desiredAccuracy: LocationAccuracy.high);
    }
    return currentLocation;
    print('${currentLocation.latitude}, ${currentLocation.longitude}');
  }

  Future<Stream> getCurrentLocationStream() async {
    await checkPermissionStatus();
//    await checkGpsService();
    final stream = getPositionStream(desiredAccuracy: LocationAccuracy.best);
    return stream;
  }

  ///
  /// [checkPermissionStatus] checks if user has not provided location
  /// access permissions using [checkPermission] provided by geolocator.
  /// If permissions status is [denied] then it request for permission using
  /// [requestPermission] which is provided by geoLocator and
  /// It request for user to provide permissions using system dialog.
  ///
  checkPermissionStatus() async {
    LocationPermission permission = await checkPermission();
    if (permission == LocationPermission.denied ||
        permission == LocationPermission.deniedForever) {
      await requestPermission();
    }
  }

  checkGpsService() async {
    if (!await isLocationServiceEnabled()) {
      showDialog(
        context: context,
        child: AlertDialog(
          title: Text('GPS is Disabled'),
          content: Text('Please turn on your GPS Location'),
          actions: [
            RaisedButton(
              child: Text('TURN ON'),
              onPressed: () async {
                await openLocationSettings();
                Navigator.pop(context);
              },
            ),
            RaisedButton(
              child: Text('Skip'),
              onPressed: () {
                Navigator.pop(context);
              },
            ),
          ],
        ),
      );
    }
  }
}