Flutter定位功能插件location_android的使用

Flutter定位功能插件location_android的使用

location_android 是 location 插件的 Android 实现。这个插件允许你在 Flutter 应用程序中获取设备的位置信息。

使用

此插件已被官方推荐为被认可的联邦插件，这意味着你可以像使用其他 Flutter 包一样正常使用 location。当你导入 location 时，location_android 会自动包含在你的应用中。

示例代码

以下是一个完整的示例代码，展示了如何使用 location 插件来获取设备的位置信息。

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

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

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

class LocationScreen extends StatefulWidget {
  @override
  _LocationScreenState createState() => _LocationScreenState();
}

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

  bool _serviceEnabled;
  PermissionStatus _permissionGranted;
  LocationData _locationData;

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

  // 检查服务是否开启和权限是否授予
  Future<void> _checkPermissionsAndServices() async {
    _serviceEnabled = await location.serviceEnabled();
    if (!_serviceEnabled) {
      _serviceEnabled = await location.requestService();
      if (!_serviceEnabled) {
        return;
      }
    }

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

    // 获取位置数据
    _getLocationData();
  }

  // 获取位置数据
  Future<void> _getLocationData() async {
    _locationData = await location.getLocation();

    // 监听位置变化
    location.onLocationChanged.listen((LocationData currentLocation) {
      setState(() {
        _locationData = currentLocation;
      });
    });

    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Flutter Location Demo'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              '纬度:',
              style: TextStyle(fontSize: 20),
            ),
            Text(
              '${_locationData?.latitude}',
              style: TextStyle(fontSize: 20),
            ),
            SizedBox(height: 20),
            Text(
              '经度:',
              style: TextStyle(fontSize: 20),
            ),
            Text(
              '${_locationData?.longitude}',
              style: TextStyle(fontSize: 20),
            ),
          ],
        ),
      ),
    );
  }
}

说明

1. 导入必要的包：

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

2. 初始化 Location 对象：

   Location location = Location();
   

3. 检查服务是否开启和权限是否授予：

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

4. 获取位置数据：

   _locationData = await location.getLocation();
   

5. 监听位置变化：

   location.onLocationChanged.listen((LocationData currentLocation) {
     setState(() {
       _locationData = currentLocation;
     });
   });