how to store the location data in flutter?

Question

import 'package:firebase_core/firebase_core.dart';
import 'package:firstapp/screens/Login_screen.dart';
import 'package:firstapp/screens/authunication/phone_auth_screen.dart';
import 'package:firstapp/screens/home_screen.dart';
import 'package:firstapp/screens/location_screen.dart';
import 'package:firstapp/screens/splash_screen.dart';
import 'package:flutter/material.dart';
import 'package:location/location.dart';

Future<void> main() async {
WidgetsFlutterBinding.ensureInitialized();
await Firebase.initializeApp();
 runApp(MyApp());
 }
 

// ignore: use_key_in_widget_constructors
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
  debugShowCheckedModeBanner: false,
  theme: ThemeData(
    primaryColor: Colors.cyan.shade900,
  ),
  initialRoute: SplashScreen.id,
  routes: {
    SplashScreen.id: (context) => SplashScreen(),
    LoginScreen.id: (context) => LoginScreen(),
    PhoneAuthScreen.id: (context) => PhoneAuthScreen(),
    LocationScreen.id: (context) => LocationScreen(),
    HomeScreen.id: (context) => HomeScreen(locationData),
  },
);`

this is main dart code where it cause the error

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

 class HomeScreen extends StatelessWidget {
 static const String id = 'home-screen';
 final LocationData locationData;
 HomeScreen({
 required this.locationData, 
 });
 @override
 Widget build(BuildContext context) {
 return Scaffold(
  appBar: AppBar(
    title: Text(locationData.latitude.toString()),
  ),
  body: Center(
    child: Text('Home screen'),
  ),
  );
   }
  }

this is the code for the home screen where i want the location data

import 'package:firebase_auth/firebase_auth.dart';
import 'package:firstapp/screens/login_screen.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:location/location.dart';



class LocationScreen extends StatefulWidget {
static const String id = 'location-screen';

@override
State<LocationScreen> createState() => _LocationScreenState();
}

class _LocationScreenState extends State<LocationScreen> {
Location location = new Location();

late bool _serviceEnabled;
late PermissionStatus _permissionGranted;
late LocationData _locationData;


 Future<LocationData?>getLocation() async {
  _serviceEnabled = await location.serviceEnabled();
  if (!_serviceEnabled) {
    _serviceEnabled = await location.requestService();
    if (!_serviceEnabled) {
    return null;
    }
   }

   _permissionGranted = await location.hasPermission();
   if (_permissionGranted == PermissionStatus.denied) {
  _permissionGranted = await location.requestPermission();
   if (_permissionGranted != PermissionStatus.granted) {
    return null;
   }
 }

   _locationData = await location.getLocation();
   return _locationData;
}

this is location screen code form app
1 the named parammeter 'locationData' is required but there is no corresponding argument try adding the required argument

2undefined name locationData try correcting the name to one that is defined or defining the name

the location data in the main dart file bring an error please help me solve it

this is the screenshot of the error

Answer 1

So,

1. The first error says that when you try to implement a HomeScreen widget, withoug giving the required parameter named locationData,to give the required parameted follow this code example:

HomeScreen(locationData: locationData)

2. The second error says that you are trying to use a variable that is not defined yet. In the page that you try to implement the HomeScreen widget, you should define a variable named locationData, to give it a value and then to try to use the HomeScreen widget. For instance:

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


  @override
  State<LocationScreen> createState() => _LocationScreenState();

}

class _LocationScreenState extends State<LocationScreen> {

  LocationData locationData;

  @override
  Widget build(BuildContext context) {
    //in case that you use the HomeScreen as a widget
    return locationData == null ? Container() : HomeScreen(locationData: locationData);
    //in case that you use the HomeScreen as Screen
    return Container();
  }

  void getLocationData() async{
    //in case that you use the HomeScreen as a widget
    //this function will change the state after the locationData have been filled
    locationData = await getLocation();
    setState(() {
    });
  }

  void navigateToHomeScreen() async{
    //in case that you use the HomeScreen as a widget
    //this function will change the state after the locationData have been filled
    locationData = await getLocation();
    Navigator.push(context, MaterialPageRoute(
        builder: (context) => HomeScreen(locationData: locationData);
    ));
  }

  Future<LocationData?> getLocation() async {
    _serviceEnabled = await location.serviceEnabled();
    if (!_serviceEnabled) {
      _serviceEnabled = await location.requestService();
      if (!_serviceEnabled) {
        return null;
      }
    }

    _permissionGranted = await location.hasPermission();
    if (_permissionGranted == PermissionStatus.denied) {
      _permissionGranted = await location.requestPermission();
      if (_permissionGranted != PermissionStatus.granted) {
        return null;
      }
    }

    _locationData = await location.getLocation();
    return _locationData;
  }
}

3. The third error says that don't use any Positional parameters in your HomeScreen class because you use named parameters, If you follow my code, it will be fixed as well

Hope I helped, Enjoy flutter

Answer 2

On the HomeScreen, replace this line of code:

HomeScreen({required this.locationData,});

with

HomeScreen(this.locationData);

This should clear the error on main.dart