如何观察GetxController类中的值更改并在Flutter中使用GetX触发statelessWidget类中的导航？

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

// 定义一个简单的控制器类
class MyController extends GetxController {
  var value = ''.obs; // 使用.obs标记这是一个响应式变量

  void updateValue(String newValue) {
    value.value = newValue;
  }
}

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return GetMaterialApp(
      home: HomeScreen(),
    );
  }
}

class HomeScreen extends StatelessWidget {
  final MyController controller = Get.put(MyController());

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Home Screen')),
      body: Center(
        child: Obx(() => ElevatedButton(
          onPressed: () {
            controller.updateValue('New Value');
          },
          child: Text(controller.value.value),
        )),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          if (controller.value.value == 'New Value') {
            Get.to(SecondScreen()); // 触发导航
          }
        },
        child: Icon(Icons.navigate_next),
      ),
    );
  }
}

class SecondScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Second Screen')),
      body: Center(
        child: Text('Welcome to the Second Screen!'),
      ),
    );
  }
}