如何从本地存储中获取令牌？

授权后，将颁发用户令牌，并保存该令牌。如果它在本地存储中可用并且在关闭应用程序后，则不需要进一步授权。这里一切正常，但是有一个 CreatePage 类，它再次需要一个令牌，我在从本地存储中获取它时遇到问题（尽管如果我直接将它插入代码中，它可以工作），服务器返回错误：“401 Unauthorized ”。flutter_secure_storage 库用于存储令牌。

AuthPage.dart

import 'dart:convert';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';
import 'package:localstorage/localstorage.dart';
import 'package:http/http.dart' as http;
import 'package:digitalpendal/main.dart';
import 'package:digitalpendal/screens/Authentication/RegistrationPage.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

class AuthPage extends StatefulWidget {
  @override
  _AuthPageState createState() => _AuthPageState();
}

class _AuthPageState extends State<AuthPage> {
  String _email;
  String _password;
  final LocalStorage storage = new LocalStorage('some_key');
  final _sizeTextBlack = const TextStyle(fontSize: 20.0, color: Colors.black);
  final _sizeTextWhite = const TextStyle(fontSize: 20.0, color: Colors.white);
  final formKey = new GlobalKey<FormState>();
  BuildContext _context;


  @override
  Widget build(BuildContext context) {
    _context = context;
    return new MaterialApp(
      debugShowCheckedModeBanner: false,
      home: new Scaffold(
        body: new Center(
          child: new Form(
              key: formKey,
              child: new Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  new Container(
                    child: new TextFormField(
                      decoration: new InputDecoration(
                        labelText: "Логин",
                        fillColor: Colors.white,
                        border: new OutlineInputBorder(
                          borderRadius: new BorderRadius.circular(25.0),
                          borderSide: new BorderSide(),
                        ),
                        //fillColor: Colors.green
                      ),
                      keyboardType: TextInputType.emailAddress,
                      maxLines: 1,
                      style: _sizeTextBlack,
                      onSaved: (val) => _email = val,
                      validator: (val) =>
                          !val.contains("@") ? 'Not a valid email.' : null,
                    ),
                    width: 340.0,
                    height: 50,
                    padding: new EdgeInsets.only(top: 10.0),
                  ),
                  new Padding(padding: new EdgeInsets.only(top: 25.0)),
                  new Container(
                    child: new TextFormField(
                      decoration: new InputDecoration(
                        labelText: "Пароль",
                        fillColor: Colors.white,
                        border: new OutlineInputBorder(
                          borderRadius: new BorderRadius.circular(25.0),
                          borderSide: new BorderSide(),
                        ),
                        //fillColor: Colors.green
                      ),
                      obscureText: true,
                      maxLines: 1,
                      validator: (val) =>
                          val.length < 2 ? 'Password too short.' : null,
                      onSaved: (val) => _password = val,
                      style: _sizeTextBlack,
                    ),
                    width: 340.0,
                    height: 50,
                    padding: new EdgeInsets.only(top: 10.0),
                  ),
                  new Padding(
                    padding: new EdgeInsets.only(top: 25.0),
                    child: new MaterialButton(
                      onPressed: submit,
                      color: Theme.of(context).accentColor,
                      height: 50.0,
                      minWidth: 150.0,
                      child: new Text(
                        "Войти",
                        style: _sizeTextWhite,
                      ),
                    ),
                  ),
                  new Padding(
                    padding: new EdgeInsets.only(top: 25.0),
                    child: new MaterialButton(
                      onPressed: submitForm,
                      color: Colors.white,
                      height: 50.0,
                      minWidth: 150.0,
                      child: new Text(
                        "Зарегистрироваться",
                        style: _sizeTextBlack,
                      ),
                    ),
                  ),
                ],
              )),
        ),
      ),
    );
  }

  void submit() {
    final form = formKey.currentState;
    if (form.validate()) {
      form.save();
      signIn();
    }
  }

  void login() {
    final form = formKey.currentState;
    if (form.validate()) {
      form.save();
      submitForm();
    }
  }

  signIn() async {
    final storage = new FlutterSecureStorage();
    Map data = {
      'email': _email,
      'password': _password
    };
    var jsonResponse = null;
    var response = await http.post("http://192.168.0.104:8000/api/v1/auth_token/token/login/", body: data);
    if(response.statusCode == 200) {
      jsonResponse = json.decode(response.body);
      if(jsonResponse != null) {
        setState(() {

        });
        await storage.write(key: "auth_token", value: 'auth_token');
        Navigator.of(_context).pushAndRemoveUntil(MaterialPageRoute(builder: (BuildContext context) => MyBottomNavigationBar()), (Route<dynamic> route) => false);
      }
    }
    else {
      setState(() {

      });
      print(response.body);
    }
  }

  void hideKeyboard() {
    SystemChannels.textInput.invokeMethod('TextInput.hide');
  }
  void fucktheAuth(){
    hideKeyboard();
    Navigator.push(_context,
        new MaterialPageRoute(builder: (context) => new MyBottomNavigationBar()));
  }



  void submitForm() {
    hideKeyboard();
    Navigator.push(_context,
        new MaterialPageRoute(builder: (context) => new RegistrationPage()));
  }
}

主要.dart

import 'package:digitalpendal/TaskPage.dart';
import 'package:digitalpendal/screens/Authentication/AuthPage.dart';
import 'package:digitalpendal/screens/Create_page/CreatePage.dart';
import 'package:digitalpendal/screens/Profile_Page.dart';
import 'package:flutter/material.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(

      theme: ThemeData(primaryColor: Colors.blue.shade900),
      debugShowCheckedModeBanner: false,
      home: MyBottomNavigationBar(),
    );
  }
}

class MyBottomNavigationBar extends StatefulWidget {
  @override
  _MyBottomNavigationBarState createState() => _MyBottomNavigationBarState();
}

class _MyBottomNavigationBarState extends State<MyBottomNavigationBar> {
  final storage = FlutterSecureStorage();

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

  checkLoginStatus() async {
    String value = await storage.read(key: 'auth_token');
    if(value == null) {
      Navigator.of(context).pushAndRemoveUntil(MaterialPageRoute(builder: (BuildContext context) => AuthPage()), (Route<dynamic> route) => false);
    }
  }
  int _currentIndex = 0;
  final List<Widget> _children = [TaskPage(), CreatePage(), Profile_Page()];

  void onTappedBar(int index) {
    setState(() {

      _currentIndex = index;
    });
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(

        resizeToAvoidBottomPadding: false,
        body: _children[_currentIndex],
        bottomNavigationBar: BottomNavigationBar(
          onTap: onTappedBar,
          currentIndex: _currentIndex,

          backgroundColor: Color.fromRGBO(48, 63, 159, 1),

          items: [
            BottomNavigationBarItem(

              icon: new Icon(
                  Icons.dashboard,
                  size: 35,
                  color: Colors.white,
                  ),

              title: new Text(
                '',
                style: new TextStyle(fontSize: 0, color: Colors.white),
              ),
              activeIcon: Theme(
                data: ThemeData(
                  accentColor: Color.fromRGBO(70, 116, 190, 1),
                ),
                child: FloatingActionButton(
                  elevation: 0,
                  onPressed: () {},
                  child: Icon(
                      Icons.dashboard,
                      size: 35,
                      color: Colors.white,),
                ),
              ),
            ),
            BottomNavigationBarItem(
                icon: new Icon(
                  Icons.add_circle,
                  size: 35,
                  color: Colors.white,
                ),
                title: new Text(
                  '',
                  style: new TextStyle(color: Colors.white, fontSize: 0),
                ),
              activeIcon: Theme(
                data: ThemeData(
                  accentColor: Color.fromRGBO(70, 116, 190, 1),
                ),
                child: FloatingActionButton(
                  elevation: 0,
                  onPressed: () {},
                  child: Icon(
                    Icons.add_circle,
                    size: 35,
                    color: Colors.white,),
                ),
              ),

            ),
            BottomNavigationBarItem(
                icon: new Icon(Icons.account_circle,
                    size: 35, color: Colors.white),
                title: new Text(
                  '',
                  style: new TextStyle(fontSize: 0, color: Colors.white),
                ),
              activeIcon: Theme(
                data: ThemeData(
                  accentColor: Color.fromRGBO(70, 116, 190, 1),
                ),
                child: FloatingActionButton(
                  elevation: 0,
                  onPressed: () {},
                  child: Icon(
                    Icons.account_circle,
                    size: 35,
                    color: Colors.white,),
                ),
              ),
            ),
          ],
        ));
  }
}

创建页面.dart

import 'dart:convert';

import 'package:digitalpendal/main.dart';
import 'package:digitalpendal/screens/Authentication/AuthPage.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';
import 'package:http/http.dart' as http;
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:localstorage/localstorage.dart';
import 'package:shared_preferences/shared_preferences.dart';


class CreatePage extends StatefulWidget {
  @override
  _CreatePageState createState() => _CreatePageState();
}

class _CreatePageState extends State<CreatePage> {


 // final LocalStorage storage = new LocalStorage('some_key');
  final formKey = new GlobalKey<FormState>();

  String _name;
  String _description;
  String _countPeople;
  String _cost;
  String _executePeriod;
  String value;



  final _sizeTextBlack = const TextStyle(fontSize: 20.0, color: Colors.black);
  final _sizeTextWhite = const TextStyle(fontSize: 20.0, color: Colors.white);
  final storage = FlutterSecureStorage();



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

  checkLoginStatus() async {
    String value = await storage.read(key: 'auth_token');
    if(value == null) {
      Navigator.of(context).pushAndRemoveUntil(MaterialPageRoute(builder: (BuildContext context) => AuthPage()), (Route<dynamic> route) => false);
    }
  }


  BuildContext _context;
  @override
  Widget build(BuildContext context) {
    _context = context;
    return new MaterialApp(
        debugShowCheckedModeBanner: false,
        home: new Scaffold(
          resizeToAvoidBottomPadding: false,
          body: new Center(
            child: SingleChildScrollView(
              child: new Form(
                  key: formKey,
                  child: new Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: <Widget>[
                      new Padding(padding: EdgeInsets.only(top: 20.0)),
                      new Container(
                        child: new TextFormField(
                          decoration: new InputDecoration(
                            labelText: "Название работы",
                            fillColor: Colors.white,
                            border: new OutlineInputBorder(
                              borderRadius: new BorderRadius.circular(25.0),
                              borderSide: new BorderSide(),
                            ),
                            //fillColor: Colors.green
                          ),
                          maxLines: 1,
                          validator: (val) =>
                          val.length < 2 ? 'Ввидите название' : null,
                          onSaved: (val) => _name = val,
                          style: _sizeTextBlack,
                        ),
                        width: 340.0,
                        height: 50,
                        margin: new EdgeInsets.only(top: 20.0),
                      ),
                      new Container(
                        child: new TextFormField(
                          decoration: new InputDecoration(
                            labelText: "Сколько людей нужно",
                            fillColor: Colors.white,
                            border: new OutlineInputBorder(
                              borderRadius: new BorderRadius.circular(25.0),
                              borderSide: new BorderSide(),
                            ),
                            //fillColor: Colors.green
                          ),
                          maxLines: 1,
                          validator: (val) =>
                          val.length < 0 ? 'количество меньше 0' : null,
                          onSaved: (val) => _countPeople = val,
                          style: _sizeTextBlack,
                        ),
                        width: 340.0,
                        height: 50,
                        margin: new EdgeInsets.only(top: 20.0),
                      ),
                      new Container(
                        child: new TextFormField(
                          decoration: new InputDecoration(
                            labelText: "Ввидите сумму",
                            fillColor: Colors.white,
                            border: new OutlineInputBorder(
                              borderRadius: new BorderRadius.circular(25.0),
                              borderSide: new BorderSide(),
                            ),
                            //fillColor: Colors.green
                          ),
                          maxLines: 1,
                          validator: (val) =>
                          val.length < 0 ? 'сумма мала' : null,
                          onSaved: (val) => _cost = val,
                          style: _sizeTextBlack,
                        ),
                        width: 340.0,
                        height: 50,
                        margin: new EdgeInsets.only(top: 20.0),
                      ),
                      new Container(
                        child: new TextFormField(
                          decoration: new InputDecoration(
                            labelText: "Срок исполнения",
                            fillColor: Colors.white,
                            border: new OutlineInputBorder(
                              borderRadius: new BorderRadius.circular(25.0),
                              borderSide: new BorderSide(),
                            ),
                            //fillColor: Colors.green
                          ),
                          maxLines: 1,
                          validator: (val) =>
                          val.length < 0 ? 'Введиnt срок выполнения' : null,
                          onSaved: (val) => _executePeriod = val,
                          style: _sizeTextBlack,
                        ),
                        width: 340.0,
                        height: 50,
                        margin: new EdgeInsets.only(top: 20.0),
                      ),
                      new Container(
                        child: new TextFormField(
                          decoration: new InputDecoration(
                            labelText: "краткое описание",
                            fillColor: Colors.white,
                            border: new OutlineInputBorder(
                              borderRadius: new BorderRadius.circular(25.0),
                              borderSide: new BorderSide(),
                            ),
                            //fillColor: Colors.green
                          ),
                          maxLines: 1,
                          validator: (val) =>
                          val.length < 2 ? 'Введите описание' : null,
                          onSaved: (val) => _description = val,
                          style: _sizeTextBlack,
                        ),
                        width: 340.0,
                        height: 50,
                        margin: new EdgeInsets.only(top: 20.0),
                      ),

                      new Padding(padding: new EdgeInsets.only(top: 50.0)),
                      new MaterialButton(
                        onPressed: submit,
                        color: Theme.of(context).accentColor,
                        height: 50.0,
                        minWidth: 150.0,
                        child: new Text(
                          "Создать",
                          style: _sizeTextWhite,
                        ),
                      ),
                    ],
                  )),
            ),
          ),
        ));
  }

  void submit() {
    final form = formKey.currentState;
    if (form.validate()) {
      form.save();
      performLogin(form);
    }
  }



  void performLogin(form) async {
    hideKeyboard();

    http.Response response = await http.post(
        Uri.encodeFull(
            'http://192.168.0.104:8000/api/v1/jobs/job/create/'),
        headers: {
          'Accept': 'application/json',
          //'Authorization': 'Token 82b6a5bcf7ad37f45de2a3e89bfea52f23bfb87a'//admin worked hardcore
          'Authorization':  value
        },
        body: {
          'name': _name,
          'description': _description,
          'count_people': _countPeople,
          'cost': _cost,
          'execute_period': _executePeriod
        });
    if (response.statusCode == 201) {
      //storage.setItem('user', jsonEncode(response.body));
      hideKeyboard();
      Navigator.push(_context,
          new MaterialPageRoute(builder: (context) => new MyBottomNavigationBar()));
    }
  }



  void hideKeyboard() {
    SystemChannels.textInput.invokeMethod('TextInput.hide');
  }
}