geo-smart-app/lib/main.dart

import 'dart:async';

import 'package:background_location/background_location.dart';
import 'package:flutter/material.dart';
import 'package:google_maps_flutter/google_maps_flutter.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Geo Smart App',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Geo Smart App'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  Completer<GoogleMapController> _controller = Completer();
  double latitude = 0.0;
  double longitude = 0.0;
  double altitude = 0.0;
  double accuracy = 0.0;
  double bearing = 0.0;
  double speed = 0.0;

  @override
  void initState() {
    super.initState();

    BackgroundLocation.startLocationService();
  }

  static final CameraPosition _kGooglePlex = CameraPosition(
    target: LatLng(-6.914744, 107.609810),
    zoom: 14.4746,
  );

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      body: GoogleMap(
        mapType: MapType.normal,
        initialCameraPosition: _kGooglePlex,
        myLocationEnabled: true,
        myLocationButtonEnabled: true,
        onMapCreated: (GoogleMapController controller) {
          _controller.complete(controller);
          BackgroundLocation.getLocationUpdates((location) async {
            setState(() {
              this.latitude = location.latitude;
              this.longitude = location.longitude;
              this.accuracy = location.accuracy;
              this.altitude = location.altitude;
              this.bearing = location.bearing;
              this.speed = location.speed;
            });
            final GoogleMapController controller = await _controller.future;
            controller.animateCamera(
              CameraUpdate.newCameraPosition(
                new CameraPosition(
                  target: LatLng(this.latitude, this.longitude),
                  zoom: 19.151926040649414,
                ),
              ),
            );
          });
        },
      ),
    );
  }

  @override
  void dispose() {
    BackgroundLocation.stopLocationService();
    super.dispose();
  }
}