无法将参数类型 'Object?' 分配给参数类型 'EditProfileScreenArgs?

Question

我正在使用 Flutter 和 Block StateManagement

当我将参数传递给路由时发生错误，它给了我这个错误：

The argument type 'Object?' can't be assigned to the parameter type 'EditProfileScreenArgs?

you can see the error in custom_router.dart

custom_router.dart

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_insta_bloc_firebase/screens/screens.dart';

class CustomRouter {
  static Route onGenerateRout(RouteSettings settings) {
    print('Route : ${settings.name}');
    switch (settings.name) {
      case '/':
        return MaterialPageRoute(
            settings: const RouteSettings(name: '/'),
            builder: (_) => Scaffold());

      case SplashScreen.routeName:
        return SplashScreen.route();

      case LoginScreen.routeName:
        return LoginScreen.route();

      case NavScreen.routeName:
        return NavScreen.route();

      default:
        return _errorRoute();
    }
  }

  static Route onGenerateNestedRout(RouteSettings settings) {
    print('Nested Route : ${settings.name}');
    switch (settings.name) {
      case EditProfileScreen.routeName:
    return EditProfileScreen.route(args: settings.arguments);

      default:
        return _errorRoute();
    }
  }

  static Route _errorRoute() {
    return MaterialPageRoute(
        settings: const RouteSettings(name: '/error'),
        builder: (_) => Scaffold(
              appBar: AppBar(
                title: const Text('Error'),
              ),
              body: const Center(
                child: Text('Some Thing went wrong!'),
              ),
            ));
  }
}

profile_button.dart

// ignore_for_file: deprecated_member_use

import 'package:flutter/material.dart';
import 'package:flutter_insta_bloc_firebase/screens/screens.dart';

class ProfileButton extends StatelessWidget {
  final bool isCurrentUser;
  final bool isFollowing;

  const ProfileButton(
      {Key? key, required this.isCurrentUser, required this.isFollowing})
      : super(key: key);

  @override
  Widget build(BuildContext context) {
    return isCurrentUser
        ? FlatButton(
            color:
                isFollowing ? Colors.grey[300] : Theme.of(context).primaryColor,
            onPressed: () => Navigator.of(context).pushNamed(
                EditProfileScreen.routeName,
                arguments: EditProfileScreenArgs(
                    context: context)), //send context for editProfileScreen
            child: Text(
              'Edite Profile',
              style: TextStyle(
                  color: isFollowing ? Colors.black : Colors.white,
                  fontSize: 16.0),
            ))
        : FlatButton(
            color:
                isFollowing ? Colors.grey[300] : Theme.of(context).primaryColor,
            onPressed: () {},
            child: Text(
              isFollowing ? 'Unfollow' : 'Follow',
              style: TextStyle(
                  color: isFollowing ? Colors.black : Colors.white,
                  fontSize: 16.0),
            ));
  }
}

Edit_Profile_screen.dart

import 'dart:js';

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_insta_bloc_firebase/repository/repository.dart';
import 'package:flutter_insta_bloc_firebase/screens/edit_profile/cubit/edite_profile_cubit.dart';
import 'package:flutter_insta_bloc_firebase/screens/pages/profile/bloc/profile_bloc.dart';
import 'package:meta/meta.dart';

//with this class we can pass argumentfor go to profile_btn
class EditProfileScreenArgs {
  final BuildContext context;

  const EditProfileScreenArgs({required this.context});
}

class EditProfileScreen extends StatelessWidget {
  static const String routeName = '/editProfile';

  static Route route({EditProfileScreenArgs? args}) {
    return MaterialPageRoute(
        settings: const RouteSettings(name: routeName),
        builder: (context) => BlocProvider<EditeProfileCubit>(
              create: (context) => EditeProfileCubit(
                  userReposirory: context.read<UserReposirory>(),
                  storageRepository: context.read<StorageRepository>(),
                  profileBloc: args!.context.read<ProfileBloc>()),
              child: EditProfileScreen(),
            ));
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Edit Profile'),
      ),
    );
  }
}

Answer 1

您需要指明传递参数的类型，否则它将被视为 Object? 类型的泛型。在 custom_router.

的 onGenerateNestedRout 方法中尝试此代码

switch (settings.name) {
      case EditProfileScreen.routeName:
    return EditProfileScreen.route(args: settings.arguments as EditProfileScreenArgs?);

      default:
        return _errorRoute();
    }