当用户更改应用程序的主题时，字体的主题无法正确重建(GetX状态管理)

import 'package:get/get.dart';

class ThemeController extends GetxController {
  Rx<ThemeData> themeData = ThemeData.light().obs;

  void changeTheme(ThemeData newTheme) {
    themeData.value = newTheme;
  }
}

import 'package:flutter/material.dart';
import 'package:get/get.dart';

import 'theme_controller.dart';

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

class MyApp extends StatelessWidget {
  final themeController = Get.put(ThemeController());

  @override
  Widget build(BuildContext context) {
    return GetMaterialApp(
      title: 'My App',
      theme: () => themeController.themeData.value,
      home: MyHomePage(),
    );
  }
}

import 'package:flutter/material.dart';
import 'package:get/get.dart';

import 'theme_controller.dart';

class MyHomePage extends StatelessWidget {
  final themeController = Get.find<ThemeController>();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('My App'),
      ),
      body: Center(
        child: Text(
          'Hello, World!',
          style: () => themeController.themeData.value.textTheme.headline6,
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          themeController.changeTheme(ThemeData.dark());
        },
        child: Icon(Icons.color_lens),
      ),
    );
  }
}