我是Flutter/Dart的新手，正在尝试编写一个登录UI，当我尝试运行程序时，调试器停在这里，errors_patch.dart，我假设它是内置的：

@pragma("vm:external-name", "AssertionError_throwNew")
  external static _doThrowNew(
      int assertionStart, int assertionEnd, Object? message);
  @pragma("vm:external-name", "AssertionError_throwNewSource")
  external static _doThrowNewSource(
      String failedAssertion, int line, int column, Object? message);

我该如何继续？我没有修改任何设置文件或其他内容。Android Studio和Flutter/Dart是最新的，并且我之前构建过此项目。此处有一些内容被破坏，但编辑器（VS代码）未指示任何错误或警告。
下面是我所有的源代码：

• lib/main.dart

import 'package:flutter/material.dart';
import 'config.dart';
import 'ui/setup/login_page.dart';

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

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

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'WiCon',
      theme: wiconTheme,
      home: const MainPage(),
    );
  }
}

class MainPage extends StatelessWidget {
  const MainPage({super.key});

  @override
  Widget build(BuildContext context) {
    return loginPage;
  }
}

• lib/ui/setup/login_page.dart

import 'package:flutter/material.dart';

var loginPage = Scaffold(

  appBar: AppBar(
    title: Row(
      children: const [
        Padding(
          padding: EdgeInsets.all(8.0),
          child: Icon(Icons.wifi),
        ),
        Padding(
          padding: EdgeInsets.all(8.0),
          child: Text("WiCon"),
        ),
      ],
    ),
  ),

  body: Row(
    children: [
      // Left side
      // Define the welcome message
      Column(
        children: const [
          Padding(
            padding: EdgeInsets.all(8.0),
            child: Text("Welcome to WiCon"),
          ),
          Padding(
            padding: EdgeInsets.all(8.0),
            child: Text("Please login to continue"),
          ),
        ],
      ),

      // Right side
      // Define the form, buttons, and status info
      Column(
        children: [
          Form(
            child: Column(
              children: [
                TextFormField(
                  decoration: const InputDecoration(labelText: "Register Number"),
                ),
                TextFormField(
                  decoration: const InputDecoration(
                    labelText: "Password",
                  ),
                  obscureText: true,
                ),
              ],
            ),
          ),
        ],
      )
    ],
  ),
);

• lib/config.dart

import 'package:flutter/material.dart';

final wiconTheme = ThemeData(
    useMaterial3: true,
    primarySwatch: Colors.blue,
);