I’m working on a Flutter project with a custom app structure that does not use MaterialApp directly for initializing the app. Instead, app configurations are managed through a custom AppConfig class. I’m trying to integrate a darkTheme configuration similar to how it’s traditionally implemented within MaterialApp.

Here’s a breakdown of my project structure:

1. AppConfig Class:
   I have an AppConfig class defined in config/app_config.dart to manage app configurations. Currently, it includes properties like appName and other custom configurations.

   class AppConfig {
     final String appName;
   
     AppConfig({
       required this.appName,
     });
   }
   

2. Main Entry Point:
   My main entry point (main.dart) initializes the app based on configurations provided by AppConfig.

   import 'package:flutter/material.dart';
   import 'config/app_config.dart';
   import 'config/app_init.dart';
   import 'restart_widget.dart';
   
   Future<void> main() async {
     AppConfig devAppConfig = AppConfig(
       appName: 'MedCare',
     );
     Widget app = await initializeApp(devAppConfig);
     runApp(RestartWidget(child: app));
   }
   

3. Desired Implementation of darkTheme:
   I want to extend the AppConfig class to include a darkTheme property and apply this theme configuration globally within my app. Ideally, I’d like to implement this darkTheme configuration in a way that mirrors how it’s typically done within MaterialApp:

   MaterialApp(
     theme: ThemeData.light(),
     darkTheme: ThemeData.dark(),
     themeMode: ThemeMode.system, // or ThemeMode.light/dark
     home: MyHomePage(),
   );
   

4. Integration Challenges:
   How can I modify my custom app initialization process to accommodate the darkTheme configuration similar to the traditional approach used within MaterialApp? Specifically, I’m looking for guidance on how to set up and apply the darkTheme globally within my app structure without relying on MaterialApp directly.

I’ve attempted to extend the AppConfig class to include a darkTheme property similar to the ThemeData.dark() approach used in MaterialApp. However, I’m unsure how to integrate this darkTheme configuration effectively within my custom app initialization process (main.dart structure).

I would greatly appreciate any advice, code examples, or best practices on how to implement and apply the darkTheme configuration in a custom Flutter app structure without using MaterialApp directly.