如何使用 sharedpreferences 保存用户角色并使用它们使用户保持登录状态并根据 flutter 中的角色导航到特定页面

Question

我正在开发一个医生咨询应用程序，我必须进行用户登录（医生登录和客户登录）。我的问题是，在关闭应用程序并重新启动后，如果医生已登录，它将转到客户的主页而不是医生的主页。在我的启动文件中，我有`

class HomeController extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final AuthService auth = Provider.of(context).auth;
    return StreamBuilder<String>(
      stream: auth.onAuthStateChanged,
      builder: (context, AsyncSnapshot<String> snapshot) {
        if (snapshot.connectionState == ConnectionState.active) {
          final bool signedIn = snapshot.hasData;
          return signedIn ? UsersHome() : OnboardingScreen();
        }
        return CircularProgressIndicator();
      },
    );
  }`
I

我想使用共享首选项在应用程序本地保存用户角色。因此，如果客户登录，它将转到 ClientHome，如果医生登录，它将转到 DoctorHome。有没有其他选择。我的后端是 firebase

我需要帮助这是我的登录页面类似于医生登录 enum AuthMode { 注册，登录 }

final primaryColor = Colors.blue;

enum AuthFormType { signIn, signUp, reset, anonymous, convert }
class Login extends StatefulWidget {

  final AuthFormType authFormType;

  Login({Key key, @required this.authFormType}) : super(key: key);
    @override
  _LoginState createState() =>
   _LoginState(authFormType: this.authFormType);
}

class _LoginState extends State<Login> {
 AuthFormType authFormType;

  _LoginState({this.authFormType});
    final formKey = GlobalKey<FormState>();
  String _email, _password, _name, _warning;

  void switchFormState(String state) {
    formKey.currentState.reset();
    if (state == "signUp") {
      setState(() {
        authFormType = AuthFormType.signUp;
      });
    } else if (state == 'home') {
      Navigator.of(context).pop();
    } else {
      setState(() {
        authFormType = AuthFormType.signIn;
      });
    }
  }


  bool validate() {
    final form = formKey.currentState;
    if (authFormType == AuthFormType.anonymous) {
      return true;
    }
    form.save();
    if (form.validate()) {
      form.save();
      return true;
    } else {
      return false;
    }
  }

  void submit() async {
    if (validate()) {
      try {
        final auth = Provider.of(context).auth;
        switch (authFormType) {
          case AuthFormType.signIn:
            await auth.signInWithEmailAndPassword(_email, _password);

            Navigator.of(context).pushReplacementNamed('/home');

            break;
          case AuthFormType.signUp:
            await auth.createUserWithEmailAndPassword
            (
                _email, _password, _name);
            Navigator.of(context).pushReplacementNamed('/home');
            break;
          case AuthFormType.reset:
            await auth.sendPasswordResetEmail(_email);
            _warning = "A password reset link has been sent to $_email";
            setState(() {
              authFormType = AuthFormType.signIn;
            });
            break;
          case AuthFormType.anonymous:
            await auth.singInAnonymously();
            Navigator.of(context).pushReplacementNamed('/home');
            break;
          case AuthFormType.convert:
            await auth.convertUserWithEmail(_email, _password, _name);
            Navigator.of(context).pop();
            break;
        }
      } catch (e) {
        print(e);
        setState(() {
          _warning = e.message;
        });
      }
    }
  }




  @override
  Widget build(BuildContext context) {
    final _auth = Provider.of(context).auth;

    return Scaffold(
      body: Container(
        width: double.infinity,
        decoration: BoxDecoration(
       color: Color(0xFF5bd75b)
        ),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: <Widget>[
            SizedBox(height: 80,),
            Padding(
              padding: EdgeInsets.all(20),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,  //m8Oq9ycK9VntE8mk8om5yoQbB10=   first one
                children: <Widget>[
                  Center(child: FadeAnimation(1, buildHeaderText(),), ),

                  SizedBox(height: 10,),

                ],
              ),
            ),
            SizedBox(height: 20),
            Expanded(
              child: Container(
                decoration: BoxDecoration(
                         color: Color(0xFF32cd32),
                  borderRadius: BorderRadius.only(topLeft: Radius.circular(60), topRight: Radius.circular(60))
                ),
                child: SingleChildScrollView(
                  child: Padding(
                    padding: EdgeInsets.all(30),
                    child: Column(
                      children: <Widget>[
                        SizedBox(height: 0,),
                        FadeAnimation(1.4, Container(

                          child: Column(
                            children: <Widget>[

                showAlert(),

                Padding(
                  padding: const EdgeInsets.all(20.0),
                  child: Form(
                    key: formKey,
                    child: Column(
                      children: buildInputs(),
                    ),
                  ),
                ),
                            ],
                          ),
                        )),
                                         SizedBox(height: 0,),
            FadeAnimation(2,
            Container(

                    child: Column(
                      children:buildButtons(),
                    ),

            )
            ),


                        SizedBox(height: 0,),
                        FadeAnimation(1.7, Text("Continue with social media", style: TextStyle(color: Colors.white),)),

                        SizedBox(height: 20,),
                        Row(
                          children: <Widget>[
                            Expanded(
                              child: FadeAnimation(1.8, Container(
                                height: 50,
                                decoration: BoxDecoration(
                                  borderRadius: BorderRadius.circular(50),
                                  color: Colors.blue
                                ),
                                child: Center(
                                  child: FlatButton(
                                    child: Text("Facebook", style: TextStyle(color: Colors.white, fontWeight: FontWeight.bold),),
                               onPressed: (){

                               },
                                )

                                ),
                              )),
                            ),
                            SizedBox(width: 30,),
                            Expanded(
                              child: FadeAnimation(1.9, Container(
                                height: 50,
                                decoration: BoxDecoration(
                                  borderRadius: BorderRadius.circular(50),
                                  color: Colors.white
                                ),
                                child: Center(

                                  child: FlatButton(

                                   child: Text("Google", style: TextStyle(color: Colors.redAccent, fontWeight: FontWeight.bold),),

                                               onPressed: () async {
                     try {
                   if(authFormType == AuthFormType.convert) {
                  await _auth.convertWithGoogle();
                  Navigator.of(context).pop();
                } else {
                  await _auth.signInWithGoogle();
                  Navigator.of(context).pushReplacementNamed('/home');
                }
              } catch (e) {
                setState(() {
                  print(e);
                  _warning = e.message;
                });
              }

                                 },

                                  ) 

                                ),
                              )),
                            )

                          ],
                        ),
                         SizedBox(height: 0),
                         FadeAnimation(3, FlatButton(child:Text('By continueing, you agree to Terms & Conditions', style: TextStyle(color: Colors.white, fontSize: 12, ),              ),          
                        onPressed: (){
                     Navigator.of(context).pushReplacementNamed('/Terms');
                        },
                        )
                        )
                      ],
                    ),
                  ),
                ),
              ),
            )
          ],
        ),
      ),
    );
  }



  Widget showAlert() {
    if (_warning != null) {
      return Container(
        color: Colors.amberAccent,
        width: double.infinity,
        padding: EdgeInsets.all(8.0),
        child: Row(
          children: <Widget>[
            Padding(
              padding: const EdgeInsets.only(right: 8.0),
              child: Icon(Icons.error_outline),
            ),
            Expanded(
              child: AutoSizeText(
                _warning,
                maxLines: 3,
              ),
            ),
            Padding(
              padding: const EdgeInsets.only(left: 8.0),
              child: IconButton(
                icon: Icon(Icons.close),
                onPressed: () {
                  setState(() {
                    _warning = null;
                  });
                },
              ),
            )
          ],
        ),
      );
    }
    return SizedBox(
      height: 0,
    );
  }

AutoSizeText buildHeaderText() {
    String _headerText;
    if (authFormType == AuthFormType.signIn) {
      _headerText = "Sign In";
    } else if (authFormType == AuthFormType.reset) {
      _headerText = "Reset Password";
    } else {
      _headerText = "Create New Account";
    }
    return AutoSizeText(
      _headerText,
      maxLines: 1,
      textAlign: TextAlign.center,
      style: TextStyle(
        fontSize: 35,
        color: Colors.white,
      ),
    );
  }


    List<Widget> buildInputs() {
    List<Widget> textFields = [];
    if (authFormType == AuthFormType.reset) {
      textFields.add(
        TextFormField(
          validator: EmailValidator.validate,
          style: TextStyle(fontSize: 22.0),
          decoration: buildSignUpInputDecoration("Email"),
          onSaved: (value) => _email = value,
        ),
      );
      textFields.add(SizedBox(height: 20));
      return textFields;
    }

    // if were in the sign up state add name
    if ([AuthFormType.signUp, AuthFormType.convert].contains(authFormType)) {
      textFields.add(
        TextFormField(
          validator: NameValidator.validate,
          style: TextStyle(fontSize: 22.0),
          decoration: buildSignUpInputDecoration("Full Name"),
          onSaved: (value) => _name = value,
        ),
      );
      textFields.add(SizedBox(height: 20));
    }

    // add email & password
    textFields.add(
      TextFormField(
        validator: EmailValidator.validate,
        style: TextStyle(fontSize: 22.0),
        decoration: buildSignUpInputDecoration("Email"),
        onSaved: (value) => _email = value,
      ),
    );
    textFields.add(SizedBox(height: 20));
    textFields.add(
      TextFormField(
        validator: PasswordValidator.validate,
        style: TextStyle(fontSize: 22.0),
        decoration: buildSignUpInputDecoration("Password"),
        obscureText: true,
        onSaved: (value) => _password = value,
      ),
    );
    textFields.add(SizedBox(height: 20));

    return textFields;
  }

  InputDecoration buildSignUpInputDecoration(String hint) {
    return InputDecoration(
      hintText: hint,
      filled: true,
      fillColor: Colors.white,
      focusColor: Colors.white,
      enabledBorder: OutlineInputBorder(
          borderSide: BorderSide(color: Colors.white, width: 0.0)),
      contentPadding:
          const EdgeInsets.only(left: 14.0, bottom: 10.0, top: 10.0),
    );
  }

  List<Widget> buildButtons() {
    String _switchButtonText, _newFormState, _submitButtonText;
    bool _showForgotPassword = false;

    if (authFormType == AuthFormType.signIn) {
      _switchButtonText = "Create New Account";
      _newFormState = "signUp";
      _submitButtonText = "Sign In";
      _showForgotPassword = true;
    } else if (authFormType == AuthFormType.reset) {
      _switchButtonText = "Return to Sign In";
      _newFormState = "signIn";
      _submitButtonText = "Submit";
    } else if (authFormType == AuthFormType.convert) {
      _switchButtonText = "Cancel";
      _newFormState = "home";
      _submitButtonText = "Sign Up";
    } else {
      _switchButtonText = "Have an Account? Sign In";
      _newFormState = "signIn";
      _submitButtonText = "Sign Up";
    }

    return [
      Container(
        width: MediaQuery.of(context).size.width * 0.7,
        child: RaisedButton(
          shape:
              RoundedRectangleBorder(borderRadius: BorderRadius.circular(30.0)),
          color: Colors.white,
          textColor: primaryColor,
          child: Padding(
            padding: const EdgeInsets.all(8.0),
            child: Text(
              _submitButtonText,
              style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.w300),
            ),
          ),
          onPressed: submit,
        ),
      ),
      showForgotPassword(_showForgotPassword),
      FlatButton(
        child: Text(
          _switchButtonText,
          style: TextStyle(color: Colors.white),
        ),
        onPressed: () {
          switchFormState(_newFormState);
        },
      ),

    ];
  }

    List<Widget> buildOre() {
    String _switchButtonText;
    bool _showForgotPassword = false;

    if (authFormType == AuthFormType.signIn) {
      _switchButtonText = "Create New Account";

      _showForgotPassword = true;
    } else if (authFormType == AuthFormType.reset) {
      _switchButtonText = "Return to Sign In";

    } else if (authFormType == AuthFormType.convert) {
      _switchButtonText = "Cancel";

    } else {
      _switchButtonText = "Have an Account? Sign In";

    }

    return [
      Container(
        width: MediaQuery.of(context).size.width * 0.7,
        child: RaisedButton(
          shape:
              RoundedRectangleBorder(borderRadius: BorderRadius.circular(30.0)),
          color: Colors.white,
          textColor: primaryColor,
          child: Padding(
            padding: const EdgeInsets.all(8.0),
            child: Text(
              ''

            ),
          ),
          onPressed: submit,
        ),
      ),
      showForgotPassword(_showForgotPassword),
      FlatButton(
        child: Text(
          _switchButtonText,
          style: TextStyle(color: Colors.white),
        ),
        onPressed: () {

        },
      ),

    ];
  }

  Widget showForgotPassword(bool visible) {
    return Visibility(
      child: FlatButton(
        child: Text(
          "Forgot Password?",
          style: TextStyle(color: Colors.white),
        ),
        onPressed: () {
          setState(() {
            authFormType = AuthFormType.reset;
          });
        },
      ),
      visible: visible,
    );
  }





}

THIS IS THE FIREBASE-FIRESTORE

THIS IS THE CODE

Answer 1

我假设 DoctorsHome 是您屏幕的名称，isDoctor 是指示用户角色是否为 'doctor' 的字段。

这样，如果用户已签名，您将根据 isDoctor 显示 DoctorHome 或 UsersHome，否则显示 OnboardingScreen。

编辑

    if (snapshot.connectionState == ConnectionState.active) {
        final bool signedIn = snapshot.hasData;
        final String role = snapshot.data['role'];
        final bool isDoctor;
        if (role=='doctor') { isDoctor = true } else { isDoctor = false}
        return signedIn ? (){ isDoctor ? DoctorsHome() : UsersHome() }() : OnboardingScreen();
    }

如何使用 sharedpreferences 保存用户角色并使用它们使用户保持登录状态并根据 flutter 中的角色导航到特定页面

How to use sharedpreferences to save users roles and use them to keep the user logged and naviagte to a specific page depending on role in flutter

firebase

flutter

firebase-authentication

sharedpreferences