我正在尝试使用 generateRoute 将多个参数传递给颤振屏幕

Question

我正在尝试按照中显示的方式执行上述操作。

我基本上想传递 2 个参数：docid 和 isCaregiver 到主屏幕，但它显示错误，没有为 class 定义参数。 class ScreenArguments 是传递 2 个参数的 class。请看代码。

ScreenArguments.dart

class ScreenArguments {
  final String docid;
  final bool isCaretaker;

  ScreenArguments({this.docid, this.isCaretaker});
}

main.dart

import 'dart:ui';
import 'package:vitality/stream.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:vitality/screens/login.dart';
import 'screens/homescreen.dart';
import 'screens/chatbot.dart';
import 'screens/todo.dart';
import 'package:vitality/screens/welcome.dart';
import 'screens/register.dart';
import 'package:firebase_core/firebase_core.dart';
import 'components/ScreenArguments.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  runApp(MyApp());
}

class ScreenArguments {
  final String reportTitle;
  final String reportFullPath;

  ScreenArguments(this.reportTitle, this.reportFullPath);
}

class Router {
  static Route<dynamic> generateRoute(RouteSettings settings) {
    final args = settings.arguments;
    switch (settings.name) {
      case Welcome.id:
        return MaterialPageRoute(builder: (_) => Welcome());
      case HomeScreen.id:
        return MaterialPageRoute(builder: (BuildContext context) {
          ScreenArguments argument = args;
          return HomeScreen(
            docid: argument.docid,
            isCaretaker: argument.isCaretaker,
          );
        });
      case LoginScreen.id:
        return MaterialPageRoute(builder: (_) => LoginScreen());
      case Register.id:
        return MaterialPageRoute(builder: (_) => Register());
      case ChatBot.id:
        return MaterialPageRoute(builder: (_) => ChatBot());
      case Todo.id:
        return MaterialPageRoute(builder: (_) => Todo());
    }
  }
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        primaryColor: Color(0xff222831),
        accentColor: Color(0xff00adb5),
        textTheme: TextTheme(
          headline1: TextStyle(
              fontSize: 15.0, fontFamily: 'Montserrat', color: Colors.black),
          headline2: TextStyle(
              fontSize: 60.0, fontFamily: 'CrimsonText', color: Colors.black),
          headline3: TextStyle(
              fontSize: 30.0, fontFamily: 'Lora', color: Colors.white),
          headline4: TextStyle(
              fontSize: 30.0, fontFamily: 'Montserrat', color: Colors.white),
        ),
      ),
      initialRoute: Welcome.id,
      routes: {
        'test': (context) => Test(),
        Welcome.id: (context) => Welcome(),
        HomeScreen.id: (context) => HomeScreen(),
        LoginScreen.id: (context) => LoginScreen(),
        Register.id: (context) => Register(),
        ChatBot.id: (context) => ChatBot(),
        Todo.id: (context) => Todo()
      },
    );
  }
}

login.dart

Button(
                        text: 'LOGIN AS INFIRM ',
                        onPressed: () {
                          doesElderlyExist();
                          print('docid after elderly function call: $docid');
                          if (docid == null) {
                            print('user does not exist');
                          } else {
                            isCaretaker = false;
                            Navigator.pushNamed(context, HomeScreen.id,
                                arguments: ScreenArguments(docid, isCaretaker));
                          }
                        }),

main.dart 中显示的错误

login.dart 中显示的错误

Answer 1

generateRoute 函数不知道您的参数是 ScreenArguments 类型，您应该明确定义：

...
case HomeScreen.id:
  return MaterialPageRoute(builder: (BuildContext context) {
    final argument = args as ScreenArguments;

    return HomeScreen(
      docid: argument.docid,
      isCaretaker: argument.isCaretaker,
    );
  });
...

还有一件事是您在 main.dart 中定义了另一个同名 ScreenArguments 的 class，仔细检查并删除未使用的那个（根据您的示例，具有 reportTitle 和 reportFullPath 属性的是“错误的”。

Answer 2

[![错误][1]][1]

这是我的错误 login.dart [1]: https://i.stack.imgur.com/hLjUV.png

这是来自 main.dart 和 route.dart

的代码

import 'dart:ui';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:vitality/screens/welcome.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:vitality/components/route.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        primaryColor: Color(0xff222831),
        accentColor: Color(0xff00adb5),
        textTheme: TextTheme(
          headline1: TextStyle(
              fontSize: 15.0, fontFamily: 'Montserrat', color: Colors.black),
          headline2: TextStyle(
              fontSize: 60.0, fontFamily: 'CrimsonText', color: Colors.black),
          headline3: TextStyle(
              fontSize: 30.0, fontFamily: 'Lora', color: Colors.white),
          headline4: TextStyle(
              fontSize: 30.0, fontFamily: 'Montserrat', color: Colors.white),
        ),
      ),
      initialRoute: Welcome.id,
      onGenerateRoute: RouteGen.generateRoute,
      // routes: {
      //   'test': (context) => Test(),
      //   Welcome.id: (context) => Welcome(),
      //   HomeScreen.id: (context) => HomeScreen(),
      //   LoginScreen.id: (context) => LoginScreen(),
      //   Register.id: (context) => Register(),
      //   ChatBot.id: (context) => ChatBot(),
      //   Todo.id: (context) => Todo()
      // },
    );
  }
}

route.dart

import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
import 'package:vitality/screens/login.dart';
import 'package:vitality/screens/homescreen.dart';
import 'package:vitality/screens/chatbot.dart';
import 'package:vitality/screens/todo.dart';
import 'package:vitality/screens/welcome.dart';
import 'package:vitality/screens/register.dart';
import 'package:vitality/components/ScreenArguments.dart';

class RouteGen {
  static Route<dynamic> generateRoute(RouteSettings settings) {
    final args = settings.arguments;
    switch (settings.name) {
      case Welcome.id:
        return MaterialPageRoute(builder: (_) => Welcome());
      case HomeScreen.id:
        return MaterialPageRoute(builder: (BuildContext context) {
          final argument = args as ScreenArguments;
          return HomeScreen(
            docid: argument.docid,
            isCaretaker: argument.isCaretaker,
          );
        });
      case LoginScreen.id:
        return MaterialPageRoute(builder: (_) => LoginScreen());
      case Register.id:
        return MaterialPageRoute(builder: (_) => Register());
      case ChatBot.id:
        return MaterialPageRoute(builder: (_) => ChatBot());
      case Todo.id:
        return MaterialPageRoute(builder: (_) => Todo());
    }
  }
}

login.dart

import 'package:flutter/material.dart';
import 'package:delayed_display/delayed_display.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:vitality/components/ScreenArguments.dart';
import 'package:vitality/screens/homescreen.dart';
import 'package:vitality/components/button.dart';
import 'package:vitality/components/ScreenArguments.dart';

bool isCaretaker = false;
String elderly;
String caretaker;
String carepass;
var docid;
CollectionReference main = FirebaseFirestore.instance.collection('maindb');

class LoginScreen extends StatefulWidget {
  @override
  _LoginScreenState createState() => _LoginScreenState();
  static const String id = 'login_screen';
}

// class arguments {
//   String id;
//   bool isCare= false;
//   arguments({this.id,this.isCare})
//   }
doesCTExist() async {
  print('in does caretaker exist');
  main.where('caretaker', isEqualTo: caretaker).get().then(
        (QuerySnapshot snapshot) => {
          snapshot.docs.forEach((f) {
            docid = f.reference.id;
          }),
        },
      );
  print('docid in caretaker function: $docid');
}

doesElderlyExist() async {
  print('in does elderly exist');
  print(elderly);
  main.where('elderly', isEqualTo: elderly).get().then(
        (QuerySnapshot snapshot) => {
          snapshot.docs.forEach((f) {
            docid = f.reference.id;
          }),
        },
      );
  print('docid in elderly function: $docid');
}

class _LoginScreenState extends State<LoginScreen> {
  final _auth = FirebaseAuth.instance;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
          backgroundColor: Color(0xFF602247),
          toolbarHeight: 50.0,
          centerTitle: true,
          title: Text(
            'VITALITY',
            style: Theme.of(context).textTheme.headline4,
          )),
      backgroundColor: Colors.white,
      body: Container(
        height: 1000,
        decoration: BoxDecoration(
            image: DecorationImage(
          image: NetworkImage(
              'https://www.fonewalls.com/wp-content/uploads/2019/10/Gradient-Background-Wallpaper-002-300x585.jpg'),
          fit: BoxFit.cover,
          colorFilter: new ColorFilter.mode(
              Colors.black.withOpacity(0.7), BlendMode.dstATop),
        )),
        child: Padding(
          padding: EdgeInsets.symmetric(horizontal: 24.0),
          child: SingleChildScrollView(
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              crossAxisAlignment: CrossAxisAlignment.stretch,
              children: <Widget>[
                DelayedDisplay(
                  delay: Duration(seconds: 1),
                  child: Column(children: <Widget>[
                    SizedBox(height: 90),
                    Text('INFIRM LOGIN',
                        textAlign: TextAlign.left,
                        style: TextStyle(fontSize: 20.0)),
                    SizedBox(height: 15.0),
                    Text('USERNAME',
                        style: Theme.of(context).textTheme.headline1),
                    SizedBox(height: 15.0),
                    TextField(
                      onChanged: (value) {
                        elderly = value;
                      },
                    ),
                    SizedBox(height: 25.0),
                    Button(
                        text: 'LOGIN AS INFIRM ',
                        onPressed: () {
                          doesElderlyExist();
                          print('docid after elderly function call: $docid');
                          if (docid == null) {
                            print('user does not exist');
                          } else {
                            isCaretaker = false;
                            // Navigator.pushNamed(context, HomeScreen.id,
                            //     arguments: docid, isCaretaker);
                            **Navigator.of(context).pushNamed('home_screen',arguments: docid,isCaretaker);**
                          }
                        }),
                    SizedBox(height: 95.0),
                    Text('CARETAKER LOGIN',
                        textAlign: TextAlign.left,
                        style: TextStyle(fontSize: 20.0)),
                    SizedBox(height: 15.0),
                    Text('USERNAME',
                        style: Theme.of(context).textTheme.headline1),
                    TextField(
                      onChanged: (value) {
                        caretaker = value;
                      },
                    ),
                    SizedBox(height: 15.0),
                    Text('PASSWORD',
                        style: Theme.of(context).textTheme.headline1),
                    TextField(
                      onChanged: (value) {
                        carepass = value;
                      },
                    ),
                    SizedBox(height: 25.0),
                    Button(
                      text: 'LOGIN AS CARETAKER',
                      onPressed: () async {
                        try {
                          doesCTExist();
                          print('docid after ct function call: $docid');
                          final user = await _auth.signInWithEmailAndPassword(
                              email: caretaker, password: carepass);
                          if (user != null) {
                            isCaretaker = true;
                            Navigator.pushNamed(context, HomeScreen.id,
                                arguments: docid);
                          }
                        } catch (e) {
                          print(e);
                        }
                      },
                    ),
                  ]),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}

我已经给出错的行加了星标（同截图）

我正在尝试使用 generateRoute 将多个参数传递给颤振屏幕

I am trying to pass multiple arguments to a flutter screen by using generateRoute

flutter

dart

flutter-navigation