flutter基于provider状态管理设置主题颜色、实现简单登录、注册功能---页面+逻辑

一、provider状态管理设置主题颜色

第一步：
安装依赖库

provider: ^4.3.2+3

第二步:
创建共享数据模型

import 'package:flutter/material.dart';
import 'package:privider_test/base/baseThemes.dart';

class ThemesViewmodel extends ChangeNotifier {
  int _index = 0;
  int get getColor {
    return _index;
  }

  void SetColor(int value) {
    if (value > themes.length - 1) return;
    _index = value;
    notifyListeners();
  }
}

在main函数中引入共享模型

第三步:
创建base颜色数组

import 'package:flutter/material.dart';

List themes = [
  Colors.green,
  Colors.yellow,
  Colors.purple,
  Colors.orange,
  Colors.cyan,
  Colors.blue,
];

在主题中使用provider状态管理，由于想让颜色的值发生改变这里我们使用statefulWidget

mian.dart

import 'package:flutter/material.dart';
import 'package:privider_test/page/UserLoginpage.dart';
import 'package:provider/provider.dart';

import 'ViewModel/ThemesViewmodel.dart';
import 'base/baseThemes.dart';

void main() {
  runApp(MultiProvider(
    providers: [
      ChangeNotifierProvider(
        create: (context) => ThemesViewmodel(),
      )
    ],
    child: MyApp(),
  ));
}

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

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

class _MyAppState extends State<MyApp> {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      home: UserLoginpage(),
      theme: ThemeData(
          primarySwatch:
              themes[Provider.of<ThemesViewmodel>(context).getColor]), //变换主题颜色
    );
  }
}

第四步:
画出ui，并添加点击事件

import 'package:flutter/material.dart';
import 'package:privider_test/ViewModel/ThemesViewmodel.dart';
import 'package:privider_test/base/baseThemes.dart';
import 'package:provider/provider.dart';
class UserLoginpage extends StatefulWidget {
  const UserLoginpage({ Key key }) : super(key: key);

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

class _UserLoginpageState extends State<UserLoginpage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("登录界面"),
      ),
      body: Padding(
        padding: EdgeInsets.all(10),
        child: Container(
       child: ListView.builder(
         shrinkWrap: true,
         itemCount: themes.length,
         itemBuilder: _itemBuilder,//如果加()就是执行这个方法,不加就是将这个返回
       ), 
      ),
      )
    );
  }
  Widget _itemBuilder(BuildContext context,int index){
    return GestureDetector(
      onTap: ()async{
        (context).read<ThemesViewmodel>().SetColor(index);
      },
      child: Container(
        margin: EdgeInsets.symmetric(vertical: 8),
        height: 50,
        width: double.infinity,
      decoration: BoxDecoration(
        borderRadius: BorderRadius.circular(8),
        color: themes[index]
      ),
    ),
    );
  }
}

二、flutter登录功能的实现

第一步：创建目录文件夹

第二步：
配置yaml文件依赖

  provider: ^4.3.2+3
  dio: ^4.0.0
  tdui: 0.0.3
  encrypt: ^5.0.1
  # 提示框
  flutter_easyloading: ^3.0.0

编写global.dart

import 'package:dio/dio.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart';

class Global {
  static Global _instance;
  Dio dio;
  String token;
  Map user;

  static Global getInstance() {
    if (_instance == null) _instance = new Global();
    return _instance;
  }

  Global() {
    dio = new Dio();
    dio.options = BaseOptions(
      baseUrl: "https://zxw.td0f7.cn/",
      // baseUrl: "http://localhost:8080/",
      connectTimeout: 5000,
      sendTimeout: 5000,
      receiveTimeout: 5000,
      contentType: Headers.formUrlEncodedContentType,
      responseType: ResponseType.json,
    );
    dio.interceptors.add(InterceptorsWrapper(
      onRequest: (options, handler) {
        EasyLoading.show(status: "Loading...");
        return handler.next(options); //continue
      },
      onResponse: (response, handler) {
        EasyLoading.dismiss();
        return handler.next(response); // continue
      },
      onError: (DioError e, handler) {
        print(e.toString());
        EasyLoading.dismiss();
        String msg = "";
        if (e.type == DioErrorType.connectTimeout) {
          msg = "连接超时错误";
        } else {
          msg = "接口错误！";
        }
        EasyLoading.showError(msg);
      },
    ));
  }
}

main.dart

import 'package:flutter/material.dart';
import 'package:myitem/router/route_handler.dart';
import 'package:myitem/view/UserLogin.dart';
import 'package:myitem/viewmodel/login_viewmodel.dart';
import 'package:provider/provider.dart';

void main() {
  runApp(
    MultiProvider(
      providers: [
        ChangeNotifierProvider(
          create: (context) => LoginViewmodel(),
        )
      ],
      child: const MyApp(),
    ),
  );
}

class MyApp extends StatelessWidget {
  const MyApp({Key key}) : super(key: key);

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const UserLogin(),
      onGenerateRoute: AppRouteManager.getInstance().onGenerateRoute,
      debugShowCheckedModeBanner: false, //去掉默认标签
    );
  }
}

loginmodel.dart

//登录数据模型
import 'package:myitem/global/Global.dart';
import 'package:myitem/util/rsa_utils.dart';

Future loginModel(String user, String pass) async {//将登录的账号和密码传入
  String pwd = await encodeString(pass);//使用rsa进行加密
  return await Global.getInstance().dio.post("/zxw/user",queryParameters: {
    "username":user,"password":pwd
  });//调用实例对象后的dio接口dio接口采用接口文档中对应的接口方式get/post提交数据，文档中
  //有固定传入参数两个主键请求的结果异步返回给viewmodel
}

/*  view层调用viewmodel，viewmodel通知model层，model再
发送请求返回给viewmodel，viewmodel处理返回结果并刷新view*/

登录界面

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:myitem/base/view.dart';
import 'package:myitem/util/rsa_utils.dart';
import 'package:myitem/viewmodel/login_viewmodel.dart';
import 'package:tdui/tdui.dart';
import 'package:provider/provider.dart';
class UserLogin extends StatefulWidget {
  const UserLogin({Key key}) : super(key: key);

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

class _UserLoginState extends State<UserLogin> {
  @override
  void initState() { 
    super.initState();

  }
  // void loadData()async{
  //   var result = await encodeString("1");
  //   print(result);
  // }
  @override
  void dispose() {
    super.dispose();//节省资源
    context.read<LoginViewmodel>().getPwd.dispose();
    context.read<LoginViewmodel>().getUser.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: getAppBar("登录"),
      body: Padding(
        padding: EdgeInsets.all(20),
        child: Column(
          children: [
            // Image.asset(
            //   "images/login.jpg",
            //   width: double.infinity,
            //   fit: BoxFit.fill,
            // ),
            SizedBox(
              height: 16,
            ),
            TextField(
              decoration: InputDecoration(
                labelText: "账号",
                hintText: "请输入账号",
                prefix: Icon(Icons.person),
              ),
              autofocus: true,
              textInputAction: TextInputAction.next,
              controller: Provider.of<LoginViewmodel>(context).getUser,
            ),
            TextField(
              controller: Provider.of<LoginViewmodel>(context).getPwd,
              decoration: InputDecoration(
                  labelText: "密码", hintText: "请输入密码", prefix: Icon(Icons.lock)),
              obscureText: true,
              textInputAction: TextInputAction.send,
            ),
            SizedBox(
              height: 16,
            ),
            GestureDetector(
              child: Container(
                width: double.infinity,
                child: Text(
                  "找回密码",
                  style: TextStyle(color: Colors.blue),
                  textAlign: TextAlign.right,
                ),
              ),
              onTap: () {
                print("找回密码");
              },
            ),
            SizedBox(
              height: 16,
            ),
            TdButton(
              '登录',
              theme: TdButtonType.primary,
              loading: Provider.of<LoginViewmodel>(context).getIsLogin,
              onClick: () {
                _login();
                // loadData();
              },
            ),
            SizedBox(
              height: 16,
            ),
            TdButton(
              '注册',
              theme: TdButtonType.primary,
              onClick: () {
                _register();
              },
            )
          ],
        ),
      ),
    );
  }

  void _login() {
    // context.read<LoginViewmodel>().setIsLogin(true);
    // new Timer(Duration(seconds: 3), () {
    //   context.read<LoginViewmodel>().setIsLogin(false);
    //   Navigator.of(context).pushNamed("/MenuPage");
    // });
    
    context.read<LoginViewmodel>().login(context);
  }

  void _register() {
    // context.read<LoginViewmodel>().setIsLogin(false);
    Navigator.of(context).pushNamed("/RegisterPage");
  }
}
/*  view层调用viewmodel，viewmodel通知model层，model再
发送请求返回给viewmodel，viewmodel处理返回结果并刷新view*/

login_viewmodel

import 'package:dio/dio.dart';
import 'package:flutter/cupertino.dart';
import 'package:myitem/model/login_model.dart';
import 'package:tdui/tdui.dart';

//创建登录状态管理
class LoginViewmodel extends ChangeNotifier {
  bool _isLogin = false;
  TextEditingController _userName; //创建controller进行全局状态管理
  TextEditingController _password;
  bool get getIsLogin {
    //返回
    return _isLogin;
  }

  TextEditingController get getUser {
    _userName ??= TextEditingController();
    //返回
    return _userName;
  }

  TextEditingController get getPwd {
    _password ??= TextEditingController(); //如果没有创建那么进行实例化
    //返回
    return _password;
  }

  // ignore: avoid_return_types_on_setters
  void setIsLogin(bool value) {
    _isLogin = value;
    notifyListeners();
  }

  void login(BuildContext context) async {
    setIsLogin(true); //先设置为true
    if (getUser.text.isEmpty) {
      //判断账号是否为空
      TdToast.fail(context)(message: "账号不能为空");
      setIsLogin(false); //如果为空那么就返回false
      return;
    } else if (getPwd.text.isEmpty) {
      //如果密码为空，那么返回false
      TdToast.fail(context)(message: "密码不能为空");
      setIsLogin(false);
      return;
    }
   //如果账号密码都不是空那么,用response接收账号和密码从viewmodel传值到数据模型
      Response result = await loginModel(getUser.text, getPwd.text);
      if (result.data["success"]) {

        Navigator.of(context).popAndPushNamed("/MenuPage");
      } else {
        TdDialog.alert(context)(result.data["msg"],
            theme: TdDialogTheme.android);
      }
      setIsLogin(false);
    
  }
}

   theme: ThemeData(primarySwatch: Colors.yellow),//变换主题颜色

实现开关功能

  TdCell(
              label: "出生日期",
              align: Alignment.center,
              content: Provider.of<RegisterViewModel>(context).getDateTime,
              footer: Row(
                children: [
                  TdSwitch(
                    checked:
                        Provider.of<RegisterViewModel>(context).getSolar == 0
                            ? false
                            : true,
                    onChange: (v) {
                      setState(() {
                        (context).read<RegisterViewModel>().SetSolar(v ? 1 : 0);
                      });
                    },
                  ),
                  SizedBox(
                    width: 8,
                  ),
                  Text(Provider.of<RegisterViewModel>(context).getSolar == 0
                      ? "阳历"
                      : "阴历")
                ],
              ),
              onClick: () async {
                DatePicker.showDatePicker(context,
                    showTitleActions: true,
                    minTime: DateTime(2010, 3, 5),
                    maxTime: DateTime(2122, 6, 7), onChanged: (date) {
                  print('change $date');
                }, onConfirm: (date) {
                  (context).read<RegisterViewModel>().SetDateTime(date);
                }, currentTime: DateTime.now(), locale: LocaleType.zh);
              },
            ),

数据模型

import 'package:flutter/material.dart';
class RegisterViewModel extends ChangeNotifier{
  DateTime _dateTime;
  int _gender = 0;//0男 1=女
  int _solar = 0;//0表阳历 1=阴历
  String get getDateTime{
    if(_dateTime == null)return "";
    return _dateTime.year.toString() + "年" +_dateTime.month.toString() +"月"+_dateTime.day.toString()+"日";
  }
  void SetDateTime(DateTime dateTime){
  _dateTime = dateTime;
   notifyListeners();
  }
  int get getGender{
    return _gender;
  }
    int get getSolar{
    return _solar;
  }
  void SetGender(int gender){
    _gender = gender;
  }
   void SetSolar(int solar){
    _solar = solar;
  }
}

三、flutter登录注册功能的实现

Register_viewmodel.dart

import 'dart:convert';
import 'package:myitem/util/rsa_utils.dart';
import 'package:dio/dio.dart';
import 'package:flutter/material.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart';
import 'package:myitem/model/register_model.dart';

class RegisterViewModel extends ChangeNotifier {
  DateTime _dateTime;
  int _gender = 0; //0男 1=女
  int _solar = 0; //0表阳历 1=阴历
  bool _getloading = false;

  bool get getloading {
    //返回
    return _getloading;
  }

  // ignore: avoid_return_types_on_setters
  void setloading(bool value) {
    _getloading = value;
    notifyListeners();
  }

  String get getDateTime {
    if (_dateTime == null) return "";
    return _dateTime.year.toString() +
        "-" +
        _dateTime.month.toString() +
        "-" +
        _dateTime.day.toString();
  }

  void SetDateTime(DateTime dateTime) {
    _dateTime = dateTime;
    notifyListeners();
  }

  int get getGender {
    return _gender;
  }

  int get getSolar {
    return _solar;
  }

  void SetGender(int gender) {
    _gender = gender;
  }

  void SetSolar(int solar) {
    _solar = solar;
  }

  void login(
      String user, String pwd, String name, String phone, String code) async {
    setloading(true);
    if (user == null || user.isEmpty) {
      EasyLoading.showToast("用户名不能为空");
    } else if (pwd == null || pwd.isEmpty) {
      EasyLoading.showToast("密码不能为空");
    } else if (phone == null || phone.isEmpty) {
      EasyLoading.showToast("手机号不能为空");
    } else if (code == null || code.isEmpty) {
      EasyLoading.showToast("验证码不能为空");
    }
      String pass = await encodeString(pwd);//使用rsa进行加密
    Response result = await RegisterModel(json.encode({
      "username": user,
      "password": pass,
      "phone": phone,
      "name": name,
      "gender": _gender,
      "birthday": getDateTime,
      "solar": _solar,
    }));
    if (result.data["success"]) {
      EasyLoading.showSuccess("success");
    } else {
      EasyLoading.showError(result.data["msg"]);
    }
    setloading(false);
    return;
  }
}

Register.dart

import 'package:flutter/material.dart';
import 'package:myitem/base/view.dart';
import 'package:myitem/viewmodel/Register_viewmodel.dart';
import 'package:provider/provider.dart';
import 'package:tdui/tdui.dart';
import 'package:flutter_datetime_picker/flutter_datetime_picker.dart';

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

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

class _RegisterPageState extends State<RegisterPage> {
  TextEditingController _user = TextEditingController();
  TextEditingController _pass = TextEditingController();
  TextEditingController _phone = TextEditingController();
  TextEditingController _code = TextEditingController();
  TextEditingController _name = TextEditingController();
  @override
  void initState() {
    super.initState();
    _user = TextEditingController();
    _pass = TextEditingController();
    _phone = TextEditingController();
    _code = TextEditingController();
    _name = TextEditingController();
  }

  @override
  void dispose() {
    super.dispose();
    _user.dispose();
    _pass.dispose();
    _phone.dispose();
    _code.dispose();
    _name.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: getAppBar("用户注册"),
      body: Container(
        child: Column(
          children: [
            SizedBox(
              height: 16,
            ),
            TdInput(
              label: "登录账号",
              hintText: "请输入登录用户名",
              clearable: true,
              textInputAction: TextInputAction.next,
              onChange: (v) {
                _user.text = v;
              },
            ),
            TdInput(
              label: "手机号码",
              hintText: "请输入手机号码",
              textInputAction: TextInputAction.send,
              type: TextInputType.phone,
              footer: TdButton(
                "获取验证码",
                theme: TdButtonType.primary,
                size: TdButtonSize.mini,
              ),
              onChange: (v) {
                _phone.text = v;
              },
            ),
            TdInput(
              label: "验证码",
              hintText: "请输入获取验证码",
              textInputAction: TextInputAction.next,
              type: TextInputType.number,
              clearable: true,
              onChange: (v) {
                _code.text = v;
              },
            ),
            TdInput(
              label: "登录密码",
              hintText: "请输入获登录密码",
              textInputAction: TextInputAction.next,
              clearable: true,
              obscureText: true,
              onChange: (v) {
                _pass.text = v;
              },
            ),
            TdInput(
              label: "中文姓名",
              hintText: "请输入中文姓名",
              textInputAction: TextInputAction.next,
              footer: Row(
                children: [
                  TdSwitch(
                    checked:
                        Provider.of<RegisterViewModel>(context).getGender == 0
                            ? false
                            : true,
                    onChange: (v) {
                      setState(() {
                        (context)
                            .read<RegisterViewModel>()
                            .SetGender(v ? 1 : 0);
                      });
                    },
                  ),
                  SizedBox(
                    width: 8,
                  ),
                  Text(Provider.of<RegisterViewModel>(context).getGender == 0
                      ? "男"
                      : "女")
                ],
              ),
              onChange: (v) {
                _name.text = v;
              },
            ),
            TdCell(
              label: "出生日期",
              align: Alignment.center,
              content: Provider.of<RegisterViewModel>(context).getDateTime,
              footer: Row(
                children: [
                  TdSwitch(
                    checked:
                        Provider.of<RegisterViewModel>(context).getSolar == 0
                            ? false
                            : true,
                    onChange: (v) {
                      setState(() {
                        (context).read<RegisterViewModel>().SetSolar(v ? 1 : 0);
                      });
                    },
                  ),
                  SizedBox(
                    width: 8,
                  ),
                  Text(Provider.of<RegisterViewModel>(context).getSolar == 0
                      ? "阳历"
                      : "阴历")
                ],
              ),
              onClick: () async {
                DatePicker.showDatePicker(context,
                    showTitleActions: true,
                    minTime: DateTime(2010, 3, 5),
                    maxTime: DateTime(2122, 6, 7), onChanged: (date) {
                  print('change $date');
                }, onConfirm: (date) {
                  (context).read<RegisterViewModel>().SetDateTime(date);
                }, currentTime: DateTime.now(), locale: LocaleType.zh);
              },
            ),
            Container(
              margin: EdgeInsets.all(10),
              child: TdButton(
                "注册",
                loading: Provider.of<RegisterViewModel>(context).getloading,
                theme: TdButtonType.warn,
                onClick: () {
                  (context).read<RegisterViewModel>().login(_user.text,
                      _pass.text, _name.text, _phone.text, _code.text);
                },
              ),
            )
          ],
        ),
      ),
    );
  }
}

register_model.dart

//登录数据模型
import 'package:myitem/global/Global.dart';


Future RegisterModel(String json) async {//将登录的账号和密码传入

  return await Global.getInstance().dio.post("/zxw/user/register",queryParameters: {
    "json":json,
  });//调用实例对象后的dio接口dio接口采用接口文档中对应的接口方式get/post提交数据，文档中
  //有固定传入参数两个主键请求的结果异步返回给viewmodel
}

main.dart

import 'package:flutter/material.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart';
import 'package:myitem/router/route_handler.dart';
import 'package:myitem/view/User/UserLogin.dart';

import 'package:myitem/viewmodel/Register_viewmodel.dart';
import 'package:myitem/viewmodel/login_viewmodel.dart';
import 'package:myitem/viewmodel/theme_viewmodel.dart';
import 'package:provider/provider.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'global/global_theme.dart';

final GlobalKey<NavigatorState> navigatorKey = GlobalKey<NavigatorState>();
void main() async {
  //持久化处理背景颜色
  WidgetsFlutterBinding.ensureInitialized();
  SharedPreferences sp = await SharedPreferences.getInstance();
  int color = await sp.getInt("color") ?? 0;
  ThemViewmodel themeViewmodel = ThemViewmodel();
  themeViewmodel.setColor(color);
//

  runApp(
    MultiProvider(
      providers: [
        ChangeNotifierProvider(
          create: (context) => LoginViewmodel(),
        ),
        ChangeNotifierProvider(
          create: (context) => themeViewmodel,
        ),
        ChangeNotifierProvider(
          create:(context)=>RegisterViewModel()
        )
      ],
      child: const MyApp(),
    ),
  );
}
void loadData()async{
  
}
class MyApp extends StatefulWidget {
  const MyApp({Key key}) : super(key: key);

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

class _MyAppState extends State<MyApp> {
  @override
  void initState() {
    super.initState();
    // initPlatformState();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      navigatorKey: navigatorKey,
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: themes[Provider.of<ThemViewmodel>(context).getColor],
        buttonTheme: ButtonThemeData(
          buttonColor: themes[Provider.of<ThemViewmodel>(context).getColor],
          textTheme: ButtonTextTheme.primary,
        ),
      ),
      home: UserLogin(),
      onGenerateRoute: AppRouteManager.getInstance().onGenerateRoute,
      debugShowCheckedModeBanner: false, //去掉默认标签
      builder: EasyLoading.init(),
    );
  }
}

由于很多变量放在了状态管理中，会大量的消耗app的内存，所以进行了一些优化
Register_viewmodel.dart

import 'dart:convert';
import 'package:flutter_easyloading/flutter_easyloading.dart';
import 'package:myitem/util/rsa_utils.dart';
import 'package:dio/dio.dart';
import 'package:flutter/material.dart';
import 'package:myitem/model/register_model.dart';

class RegisterViewModel extends ChangeNotifier {
  void login(String user, String pwd, String name, String phone, String code,
    int _gender, int _solar, String getDateTime) async {
    String pass = await encodeString(pwd); //使用rsa进行加密
    Response result = await RegisterModel(json.encode({
      "username": user,
      "password": pass,
      "phone": phone,
      "name": name,
      "gender": _gender,
      "birthday": getDateTime,
      "solar": _solar,
    }));
    if (result.data["success"]) {
      EasyLoading.showToast("注册成功");
      // Navigator.pop(navigatorKey.currentContext, {
      //   "user": user,
      //   "pass": pass,
      // }
      // );
    } else {
      EasyLoading.showError(result.data["msg"]);
    }
    return;
  }
}

date_util.dart

//修改日期
String getDate(DateTime _dateTime) {
  return _dateTime == null
      ? ""
      : _dateTime.year.toString() +
          "-" +
          _dateTime.month.toString() +
          "-" +
          _dateTime.day.toString();
}

Register.dart

import 'package:flutter/material.dart';
import 'package:myitem/base/view.dart';
import 'package:myitem/util/date_util.dart';
import 'package:myitem/viewmodel/Register_viewmodel.dart';
import 'package:provider/provider.dart';
import 'package:tdui/tdui.dart';
import 'package:flutter_datetime_picker/flutter_datetime_picker.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart';

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

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

class _RegisterPageState extends State<RegisterPage> {
  TextEditingController _user = TextEditingController();
  TextEditingController _pass = TextEditingController();
  TextEditingController _phone = TextEditingController();
  TextEditingController _code = TextEditingController();
  TextEditingController _name = TextEditingController();
  DateTime _dateTime;
  int _gender = 0; //0男 1=女
  int _solar = 0; //0表阳历 1=阴历
  @override
  void initState() {
    super.initState();
    _user = TextEditingController();
    _pass = TextEditingController();
    _phone = TextEditingController();
    _code = TextEditingController();
    _name = TextEditingController();
  }

  @override
  void dispose() {
    super.dispose();
    _user.dispose();
    _pass.dispose();
    _phone.dispose();
    _code.dispose();
    _name.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: getAppBar("用户注册"),
      body: Container(
        child: Column(
          children: [
            SizedBox(
              height: 16,
            ),
            TdInput(
              label: "登录账号",
              hintText: "请输入登录用户名",
              clearable: true,
              textInputAction: TextInputAction.next,
              onChange: (v) {
                _user.text = v;
              },
            ),
            TdInput(
              label: "手机号码",
              hintText: "请输入手机号码",
              textInputAction: TextInputAction.send,
              type: TextInputType.phone,
              footer: TdButton(
                "获取验证码",
                theme: TdButtonType.primary,
                size: TdButtonSize.mini,
              ),
              onChange: (v) {
                _phone.text = v;
              },
            ),
            TdInput(
              label: "验证码",
              hintText: "请输入获取验证码",
              textInputAction: TextInputAction.next,
              type: TextInputType.number,
              clearable: true,
              onChange: (v) {
                _code.text = v;
              },
            ),
            TdInput(
              label: "登录密码",
              hintText: "请输入获登录密码",
              textInputAction: TextInputAction.next,
              clearable: true,
              obscureText: true,
              onChange: (v) {
                _pass.text = v;
              },
            ),
            TdInput(
              label: "中文姓名",
              hintText: "请输入中文姓名",
              textInputAction: TextInputAction.next,
              footer: Row(
                children: [
                  TdSwitch(
                    checked: _gender == 0 ? false : true,
                    onChange: (v) {
                      setState(() {
                        v ? _gender = 1 : _gender = 0;
                      });
                    },
                  ),
                  SizedBox(
                    width: 8,
                  ),
                  Text(_gender == 0 ? "男" : "女")
                ],
              ),
              onChange: (v) {
                _name.text = v;
              },
            ),
            TdCell(
              label: "出生日期",
              align: Alignment.center,
              content: getDate(_dateTime),
              footer: Row(
                children: [
                  TdSwitch(
                    checked: _solar == 0 ? false : true,
                    onChange: (v) {
                      setState(() {
                        v ? _solar = 1 : _solar = 0;
                      });
                    },
                  ),
                  SizedBox(
                    width: 8,
                  ),
                  Text(_solar == 0 ? "阳历" : "阴历")
                ],
              ),
              onClick: () async {
                DatePicker.showDatePicker(context,
                    showTitleActions: true,
                    minTime: DateTime(2010, 3, 5),
                    maxTime: DateTime(2122, 6, 7),
                    onChanged: (date) {}, onConfirm: (date) {
                setState(() {
                                    _dateTime = date;
                                });
                }, currentTime: DateTime.now(), locale: LocaleType.zh);
              },
            ),
            Container(
              margin: EdgeInsets.all(10),
              child: TdButton(
                "注册",
                theme: TdButtonType.warn,
                onClick: () {
                    _register();
                },
              ),
            )
          ],
        ),
      ),
    );
  }

  void _register() {
    print("object");
    if (_user.text == null || _user.text.isEmpty) {
      EasyLoading.showToast("用户名不能为空");
    } else if (_pass.text == null || _pass.text.isEmpty) {
      EasyLoading.showToast("密码不能为空");
    } else if (_phone.text == null || _phone.text.isEmpty) {
      EasyLoading.showToast("手机号不能为空");
    } else if (_code.text == null || _code.text.isEmpty) {
      EasyLoading.showToast("验证码不能为空");
    }
    (context).read<RegisterViewModel>().login(_user.text, _pass.text,
        _name.text, _phone.text, _code.text, _gender, _solar, getDate(_dateTime));
  }
}

用路由传值返回对象，实现注册后，可以在登录界面保留注册账户信息
Register_viewmodel.dart

import 'dart:convert';
import 'package:flutter_easyloading/flutter_easyloading.dart';
import 'package:myitem/main.dart';
import 'package:myitem/util/rsa_utils.dart';
import 'package:dio/dio.dart';
import 'package:flutter/material.dart';
import 'package:myitem/model/register_model.dart';

class RegisterViewModel extends ChangeNotifier {
  void login(String user, String pwd, String name, String phone, String code,
      int _gender, int _solar, String getDateTime) async {
    String pass = await encodeString(pwd); //使用rsa进行加密
    Response result = await RegisterModel(json.encode({
      "username": user,
      "password": pass,
      "phone": phone,
      "name": name,
      "gender": _gender,
      "birthday": getDateTime,
      "solar": _solar,
    }));
    if (result.data["success"]) {
      Navigator.pop(navigatorKey.currentContext, {
        "user": user,
        "pass": pwd,
      });
      EasyLoading.showSuccess("注册成功");
    } else {
      EasyLoading.showError(result.data["msg"]);
    }
    return;
  }
}

UserLogin_view.dart

import 'package:flutter/material.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart';
import 'package:myitem/base/view.dart';
import 'package:myitem/global/Global.dart';
import 'package:myitem/viewmodel/login_viewmodel.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:tdui/tdui.dart';
import 'package:provider/provider.dart';

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

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

class _UserLoginState extends State<UserLogin> {
  TextEditingController _userName; //创建controller进行全局状态管理
  TextEditingController _password;
  @override
  void initState() {
    super.initState();
    _userName = TextEditingController();
    _password = TextEditingController();
    // loadData();
  }

  @override
  void dispose() {
    super.dispose(); //节省资源
    _userName.dispose();
    _password.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: getAppBar("登录"),
      body: Padding(
        padding: EdgeInsets.all(20),
        child: Column(
          children: [
            SizedBox(
              height: 16,
            ),
            TextField(
              decoration: InputDecoration(
                labelText: "账号",
                hintText: "请输入账号",
                prefix: Icon(Icons.person),
              ),
              autofocus: true,
              textInputAction: TextInputAction.next,
              controller: _userName,
            ),
            TextField(
              controller: _password,
              decoration: InputDecoration(
                  labelText: "密码", hintText: "请输入密码", prefix: Icon(Icons.lock)),
              obscureText: true,
              textInputAction: TextInputAction.send,
            ),
            SizedBox(
              height: 16,
            ),
            GestureDetector(
              child: Container(
                width: double.infinity,
                child: Text(
                  "找回密码",
                  style: TextStyle(color: Colors.blue),
                  textAlign: TextAlign.right,
                ),
              ),
              onTap: () {
                print("找回密码");
              },
            ),
            SizedBox(
              height: 16,
            ),
            TdButton(
              '登录',
              theme: TdButtonType.primary,
              onClick: () {
                _login();
              },
            ),
            SizedBox(
              height: 16,
            ),
            TdButton(
              '注册',
              theme: TdButtonType.primary,
              onClick: () {
                _register();
              },
            )
          ],
        ),
      ),
    );
  }

  void _login() {
    if (_userName.text.isEmpty) {
      EasyLoading.showError("账号不能为空");
      return;
    } else if (_password.text.isEmpty) {
      EasyLoading.showError("密码不能为空");
      return;
    }
    context.read<LoginViewmodel>().login(_userName.text, _password.text);
  }

  void _register() async {
    dynamic params = await Navigator.of(context).pushNamed("/RegisterPage");

    if (params != null) {
      setState(() {
        _userName.text = params["user"];
        _password.text = params["pass"];
      });
    }
  }

  void loadData() async {
    SharedPreferences sp = await SharedPreferences.getInstance();
    String token = await sp.getString("token");
    print(token);
    if (token != null) {
      //将里面的token对象赋值到获取的token值
      Global.getInstance().dio.options.headers["token"] = token;
      context.read<LoginViewmodel>().tokenLogin(token);
    }
  }
}

/*  view层调用viewmodel，viewmodel通知model层，model再
发送请求返回给viewmodel，viewmodel处理返回结果并刷新view*/

持久化管理，报错token值

login_viewmodel.dart

import 'package:dio/dio.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart';
import 'package:myitem/global/Global.dart';
import 'package:myitem/model/login_model.dart';
import 'package:shared_preferences/shared_preferences.dart';
import '../main.dart';

//创建登录状态管理
class LoginViewmodel extends ChangeNotifier {
  void login(String user, String pass) async {
    //持久化管理
    SharedPreferences sp = await SharedPreferences.getInstance();
    Response result = await loginModel(user, pass);
    if (result.data["success"]) {
      Global.getInstance().token = result.data["data"]["token"];
      Global.getInstance().user = result.data["data"]["user"];
      sp.setString("token", result.data["data"]["token"]);
      Global.getInstance().dio.options.headers["token"] =
          result.data["data"]["token"];
      //下次验证token是不是过期了
      EasyLoading.showSuccess("success");
      Navigator.of(navigatorKey.currentContext).popAndPushNamed("/MenuPage");
    } else {
      EasyLoading.showError(result.data["msg"]);
    }
  }

  void tokenLogin(String token) async {
    SharedPreferences sp = await SharedPreferences.getInstance();
    Response result = await tokenLoginModel();
    if (result.data["success"]) {
      //如果请求成功
      Global.getInstance().user =
          result.data["data"]; //将将请求结果中的data赋值为gobal中的user
      Navigator.of(navigatorKey.currentContext).popAndPushNamed("/menu"); //跳转路由
    } else {
      sp.remove("token"); //如果不成功就移除持久化管理中创建的token对象
    }
  }
}

login_viewmodel.dart

import 'package:dio/dio.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart';
import 'package:myitem/global/Global.dart';
import 'package:myitem/model/login_model.dart';
import 'package:shared_preferences/shared_preferences.dart';
import '../main.dart';

//创建登录状态管理
class LoginViewmodel extends ChangeNotifier {
  void login(String user, String pass) async {
    //持久化管理
    SharedPreferences sp = await SharedPreferences.getInstance();
    Response result = await loginModel(user, pass);
    if (result.data["success"]) {
      Global.getInstance().token = result.data["data"]["token"];
      Global.getInstance().user = result.data["data"]["user"];
      sp.setString("token", result.data["data"]["token"]);
      Global.getInstance().dio.options.headers["token"] =
          result.data["data"]["token"];
      //下次验证token是不是过期了
      EasyLoading.showSuccess("success");
      Navigator.of(navigatorKey.currentContext).popAndPushNamed("/MenuPage");
    } else {
      EasyLoading.showError(result.data["msg"]);
    }
  }

  void tokenLogin(String token) async {
    SharedPreferences sp = await SharedPreferences.getInstance();
    Response result = await tokenLoginModel();
    if (result.data["success"]) {
      //如果请求成功
      Global.getInstance().user =
          result.data["data"]; //将将请求结果中的data赋值为gobal中的user
      Navigator.of(navigatorKey.currentContext).popAndPushNamed("/menu"); //跳转路由
    } else {
      sp.remove("token"); //如果不成功就移除持久化管理中创建的token对象
    }
  }
}