flutter: 用getxservice管理状态

一，安装所需的库：flutter_secure_storage

地址:

https://pub.dev/packages/flutter_secure_storage/install

安装：

dependencies:flutter_secure_storage: ^10.0.0

二，代码

service

import 'package:get/get.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';class AuthService extends GetxService {final storage = FlutterSecureStorage();//是否登录RxBool isLoggedIn = false.obs;//用户tokenRxString userToken = "".obs;//登录Future<void> login(String tokenStr) async {await storage.write(key: 'token', value: tokenStr);isLoggedIn.value = true;userToken.value = tokenStr;}//退出Future<void> logout() async {await storage.delete(key: 'token');isLoggedIn.value = false;userToken.value = "";}//从磁盘读取保存的数据Future<void> getDataFromDisk() async {String? value = await storage.read(key: 'token');if (value == null) {print("数据不存在");isLoggedIn.value = false;userToken.value = "";} else {print("读取到数据"+value);isLoggedIn.value = true;userToken.value = value;}}@overridevoid onInit() {super.onInit();getDataFromDisk();print('AuthService initialized');}

main中初始化

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'services/AuthService.dart';
import 'routes/routes.dart';void main() {Get.put(AuthService());runApp(const MyApp());
}class MyApp extends StatelessWidget {const MyApp({super.key});@overrideWidget build(BuildContext context) {return   GetMaterialApp(debugShowCheckedModeBanner: false, //去除debug图标defaultTransition: Transition.rightToLeft,   //指定动画theme: ThemeData(primarySwatch: Colors.red),initialRoute: "/",    //初始化页面getPages: APPage.routes,   //路由);}}

页面中调用：

import 'package:flutter/material.dart';
import 'package:get/get.dart';import '../services/AuthService.dart';class HomePage extends StatefulWidget {@overrideState<HomePage> createState() => _HomePageState();
}class _HomePageState extends State<HomePage>  {var authServ = Get.find<AuthService>();@overrideWidget build(BuildContext context) {return Scaffold(appBar: AppBar(backgroundColor: Theme.of(context).colorScheme.inversePrimary,title: const Text("home页面"),),body: Center(child:Column(children:[ElevatedButton(child: Text("跳转到detail页面"),onPressed: () {Get.toNamed("/detail",arguments: {"id":20,"name":"苏东坡新传",});},),SizedBox(height: 30,),Obx(() => Text('当前是否登录: ${authServ.isLoggedIn.value}')),Obx(() => Text('当前用户token: ${authServ.userToken.value}')),SizedBox(height: 30,),ElevatedButton(child: Text("登录"),onPressed: () async {authServ.login('老刘123321');},),SizedBox(height: 30,),ElevatedButton(child: Text("退出"),onPressed: () async {authServ.logout();},),],),),);}}

三，测试效果：