Not using useReducer

not-using-usereducer.dart

import 'package:flutter/material.dart';  
import 'package:flutter_hooks/flutter_hooks.dart';  
import 'package:use_reducer_example/reducer.dart';  
  
final itemsForDropdown1 = ['A', 'B', 'C'];  
final itemsForDropdown2 = ['1', '2', '3'];  
  
enum Stage { dropdown1, textInput, dropdown2, finished }  
  
class MyFormUseStateView extends HookWidget {  
  const MyFormUseStateView({super.key});  
  
  @override  
  Widget build(BuildContext context) {  
    final dropdown1Value = useState<String?>(null);  
    final textInputController = useTextEditingController();  
    final dropdown2Value = useState<String?>(null);  
    final stage = useState<Stage>(Stage.dropdown1);  
    final formKey = useState(GlobalKey<FormState>());  
  
    return Form(  
      key: formKey.value,  
      child: Center(  
        child: Column(  
          children: <Widget>[  
            if (stage.value == Stage.dropdown1 || stage.value == Stage.textInput || stage.value == Stage.dropdown2)  
              DropdownButton<String>(  
                value: dropdown1Value.value,  
                items:  
                    itemsForDropdown1.map((item) => DropdownMenuItem<String>(value: item, child: Text(item))).toList(),  
                onChanged: (value) {  
                  dropdown1Value.value = value;  
                  textInputController.clear();  
                  stage.value = Stage.textInput;  
                },  
              ),  
            if (stage.value == Stage.textInput)  
              Column(  
                children: <Widget>[  
                  TextFormField(  
                    controller: textInputController,  
                    validator: (value) => validate(value),  
                  ),  
                  ElevatedButton(  
                    onPressed: () {  
                      if (formKey.value.currentState!.validate()) {  
                        stage.value = Stage.dropdown2;  
                      }  
                    },  
                    child: const Text('Submit'),  
                  ),  
                ],  
              ),  
            if (stage.value == Stage.dropdown2) ...[  
              Text(textInputController.text),  
              DropdownButton<String>(  
                value: dropdown2Value.value,  
                items:  
                    itemsForDropdown2.map((item) => DropdownMenuItem<String>(value: item, child: Text(item))).toList(),  
                onChanged: (value) {  
                  dropdown2Value.value = value;  
                  stage.value = Stage.finished;  
                },  
              ),  
            ],  
            if (stage.value == Stage.finished)  
              Column(  
                children: <Widget>[  
                  Text('Dropdown 1: ${dropdown1Value.value}'),  
                  Text('Text Input: ${textInputController.text}'),  
                  Text('Dropdown 2: ${dropdown2Value.value}'),  
                  ElevatedButton(  
                    onPressed: () {  
                      dropdown1Value.value = null;  
                      textInputController.clear();  
                      dropdown2Value.value = null;  
                      stage.value = Stage.dropdown1;  
                    },  
                    child: const Text('Reset'),  
                  ),  
                ],  
              ),  
          ],  
        ),  
      ),  
    );  
  }  
}