HomePage.java

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

class HomePage extends StatefulWidget {
const HomePage({Key? key}) : super(key: key);

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

class _HomePageState extends State<HomePage> {
Completer<GoogleMapController> _controller = Completer();
// on below line we have specified camera position
static final CameraPosition _kGoogle = const CameraPosition(
	target: LatLng(20.42796133580664, 80.885749655962),
	zoom: 14.4746,
);

// on below line we have created the list of markers
final List<Marker> _markers = <Marker>[
	Marker(
		markerId: MarkerId('1'),
	position: LatLng(20.42796133580664, 75.885749655962),
	infoWindow: InfoWindow(
		title: 'My Position',
	)
),
];
final _polyline = <Polyline>[];

// created method for getting user current location
Future<Position> getUserCurrentLocation() async {
	await Geolocator.requestPermission().then((value){
	}).onError((error, stackTrace) async {
	await Geolocator.requestPermission();
	print("ERROR"+error.toString());
	});
	return await Geolocator.getCurrentPosition();
}

@override
Widget build(BuildContext context) {
	return Scaffold(
	appBar: AppBar(
		backgroundColor: Color(0xFF0F9D58),
		// on below line we have given title of app
		title: Text("GFG"),
	),
	body: Container(
		child: SafeArea(
		// on below line creating google maps
		child: GoogleMap(
		// on below line setting camera position
		initialCameraPosition: _kGoogle,
		// on below line we are setting markers on the map
		markers: Set<Marker>.of(_marker),
			polylines: Set<Polyline>.of(_polyline),
		// on below line specifying map type.
		mapType: MapType.normal,
		// on below line setting user location enabled.
		myLocationEnabled: true,
		// on below line setting compass enabled.
		compassEnabled: true,
		// on below line specifying controller on map complete.
		onMapCreated: (GoogleMapController controller){
				_controller.complete(controller);
			},
		),
		),
	),
	// on pressing floating action button the camera will take to user current location
	floatingActionButton: FloatingActionButton(
		onPressed: () async{
		getUserCurrentLocation().then((value) async {
			print(value.latitude.toString() +" "+value.longitude.toString());

			// marker added for current users location
			_markers.add(
				Marker(
				markerId: MarkerId("1"),
				position: LatLng(value.latitude, value.longitude),
				infoWindow: InfoWindow(
					title: 'My Current Location',
				),
				)
			);
			print('${value.latitude + 0.01} ${value.longitude + 0.01}');
			_markers.add(
					Marker(
							markerId: MarkerId("2"),
					position: LatLng(value.latitude + 0.01, value.longitude + 0.01
					infoWindow: InfoWindow(
					title: 'nEW LOCATIONn',
				),
				)
			);

			_polyline.add(
				Polyline(
					polylineId: PolylineId("1"),
					visible: true,
					points: [
						LatLng(value.latitude, value.longitude),
						LatLng(value.latitude + 0.01, value.longitude + 0.01),
					],
					width: 5,
					color: Colors.red,
					polylineId: PolylineId("distance"),
				)
			);

			// specified current users location
			CameraPosition cameraPosition = new CameraPosition(
			target: LatLng(value.latitude + 0.01, value.longitude + 0.01),
			zoom: 14,
			);

			final GoogleMapController controller = await _controller.future;
			controller.animateCamera(CameraUpdate.newCameraPosition(cameraPosition));
			setState(() {
			});
		});
		},
		child: Icon(Icons.local_activity),
	),
	);
}
}