使用库：location

在pubspec.yaml中导入：

dependencies:
  #地理位置
  location: ^2.3.5

示例代码：

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

import 'package:flutter/material.dart';

//地理位置
import 'package:location/location.dart';

class WSLocation extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: LocationPage(title: 'Flutter Demo Home Page'),
    );
  }
}

class LocationPage extends StatefulWidget {
  LocationPage({Key key, this.title}) : super(key: key);
  final String title;
  @override
  LocationPageState createState() => LocationPageState();
}

class LocationPageState extends State<LocationPage> {
  int _counter = 0;

  LocationData currentLocation;

  var location = new Location();

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

  _incrementCounter() async {
    try {
      currentLocation = await location.getLocation();
    } catch (e) {
      if (e.code == 'PERMISSION_DENIED') {
        print('Permission denied');
      }
      currentLocation = null;
    }

    location.onLocationChanged().listen((LocationData currentLocation) {
      print(currentLocation.latitude);
      print(currentLocation.longitude);
    });

    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed PATHText $_counter the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
}