Without statemanagement/BLOC,riverpod like statemanagement not allow need to use native flutter any possible way to update the state of the widget or how we can develop the app without state management?

Overview

Yes, you can develop Flutter apps without external state management packages by using native Flutter techniques:

setState

InheritedWidget

ValueNotifier

StreamBuilder

Method 1: setState (Simplest)

For simple, local state in a single widget.

Example: Counter App

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class CounterScreen extends StatefulWidget {
  @override
  _CounterScreenState createState() => _CounterScreenState();
}

class _CounterScreenState extends State<CounterScreen> {
  int _counter = 0;

  void _increment() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Counter')),
      body: Center(
        child: Text('Count: $_counter', style: TextStyle(fontSize: 32)),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _increment,
        child: Icon(Icons.add),
      ),
    );
  }
}

Pros:

• ✅ Simple
• ✅ No dependencies
• ✅ Good for local state

Cons:

• ❌ Only works within one widget
• ❌ Cannot share state with other widgets

Method 2: InheritedWidget (Share State Down the Tree)

Share state with descendant widgets.

Example: Theme State

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// 1. Create InheritedWidget
class AppState extends InheritedWidget {
  final bool isDarkMode;
  final Function toggleTheme;

  AppState({
    required this.isDarkMode,
    required this.toggleTheme,
    required Widget child,
  }) : super(child: child);

  static AppState? of(BuildContext context) {
    return context.dependOnInheritedWidgetOfExactType<AppState>();
  }

  @override
  bool updateShouldNotify(AppState oldWidget) {
    return oldWidget.isDarkMode != isDarkMode;
  }
}

// 2. Wrap app with StatefulWidget + InheritedWidget
class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  bool _isDarkMode = false;

  void _toggleTheme() {
    setState(() {
      _isDarkMode = !_isDarkMode;
    });
  }

  @override
  Widget build(BuildContext context) {
    return AppState(
      isDarkMode: _isDarkMode,
      toggleTheme: _toggleTheme,
      child: MaterialApp(
        theme: _isDarkMode ? ThemeData.dark() : ThemeData.light(),
        home: HomeScreen(),
      ),
    );
  }
}

// 3. Access state in child widgets
class HomeScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final appState = AppState.of(context)!;

    return Scaffold(
      appBar: AppBar(title: Text('Home')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text('Dark Mode: ${appState.isDarkMode}'),
            ElevatedButton(
              onPressed: () => appState.toggleTheme(),
              child: Text('Toggle Theme'),
            ),
          ],
        ),
      ),
    );
  }
}

Pros:

• ✅ Share state with descendants
• ✅ No external dependencies
• ✅ Efficient (only rebuilds dependents)

Cons:

• ⚠️ More boilerplate than packages
• ⚠️ Only works down the tree (not up)

Method 3: ValueNotifier + ValueListenableBuilder

For simple observable state.

Example: Todo List

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class TodoScreen extends StatefulWidget {
  @override
  _TodoScreenState createState() => _TodoScreenState();
}

class _TodoScreenState extends State<TodoScreen> {
  final ValueNotifier<List<String>> _todos = ValueNotifier([]);

  void _addTodo(String todo) {
    _todos.value = [..._todos.value, todo];
  }

  @override
  void dispose() {
    _todos.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Todo List')),
      body: Column(
        children: [
          TextField(
            onSubmitted: _addTodo,
            decoration: InputDecoration(labelText: 'Add Todo'),
          ),
          Expanded(
            child: ValueListenableBuilder<List<String>>(
              valueListenable: _todos,
              builder: (context, todos, child) {
                return ListView.builder(
                  itemCount: todos.length,
                  itemBuilder: (context, index) {
                    return ListTile(title: Text(todos[index]));
                  },
                );
              },
            ),
          ),
        ],
      ),
    );
  }
}

Pros:

• ✅ Simple observable pattern
• ✅ No external dependencies
• ✅ Efficient (only rebuilds listeners)

Cons:

• ⚠️ Limited to single values
• ⚠️ Not suitable for complex state

Method 4: StreamBuilder (Reactive Streams)

For asynchronous state updates.

Example: Real-Time Counter

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import 'dart:async';

class CounterScreen extends StatefulWidget {
  @override
  _CounterScreenState createState() => _CounterScreenState();
}

class _CounterScreenState extends State<CounterScreen> {
  final StreamController<int> _counterController = StreamController<int>();
  int _counter = 0;

  void _increment() {
    _counter++;
    _counterController.add(_counter);
  }

  @override
  void dispose() {
    _counterController.close();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Stream Counter')),
      body: Center(
        child: StreamBuilder<int>(
          stream: _counterController.stream,
          initialData: 0,
          builder: (context, snapshot) {
            return Text('Count: ${snapshot.data}', style: TextStyle(fontSize: 32));
          },
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _increment,
        child: Icon(Icons.add),
      ),
    );
  }
}

Pros:

• ✅ Reactive updates
• ✅ No external dependencies
• ✅ Good for async data (API, WebSocket)

Cons:

• ⚠️ More complex than
  textCopy

  setState

• ⚠️ Must manually manage StreamController

Method 5: ChangeNotifier + AnimatedBuilder

For more complex state with multiple listeners.

Example: Shopping Cart

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import 'package:flutter/foundation.dart';

class Cart extends ChangeNotifier {
  List<String> _items = [];

  List<String> get items => _items;

  void addItem(String item) {
    _items.add(item);
    notifyListeners(); // Notify listeners
  }

  void removeItem(String item) {
    _items.remove(item);
    notifyListeners();
  }
}

class CartScreen extends StatefulWidget {
  @override
  _CartScreenState createState() => _CartScreenState();
}

class _CartScreenState extends State<CartScreen> {
  final Cart _cart = Cart();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Cart')),
      body: Column(
        children: [
          ElevatedButton(
            onPressed: () => _cart.addItem('Item ${_cart.items.length + 1}'),
            child: Text('Add Item'),
          ),
          Expanded(
            child: AnimatedBuilder(
              animation: _cart,
              builder: (context, child) {
                return ListView.builder(
                  itemCount: _cart.items.length,
                  itemBuilder: (context, index) {
                    return ListTile(
                      title: Text(_cart.items[index]),
                      trailing: IconButton(
                        icon: Icon(Icons.delete),
                        onPressed: () => _cart.removeItem(_cart.items[index]),
                      ),
                    );
                  },
                );
              },
            ),
          ),
        ],
      ),
    );
  }
}

Pros:

• ✅ Multiple listeners
• ✅ No external dependencies
• ✅ Flutter SDK built-in

Cons:

• ⚠️ Less structured than BLoC/Riverpod

Comparison: Native Flutter State Management

When to Use Each

setState

✅ Simple counters, toggles, form inputs

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setState(() {
  _isChecked = !_isChecked;
});

InheritedWidget

✅ Theme, localization, auth state (shared across app)

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final theme = AppTheme.of(context);

ValueNotifier

✅ Observable single values (search query, selected item)

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ValueListenableBuilder(
  valueListenable: searchQuery,
  builder: (context, query, child) => Text(query),
)

StreamBuilder

✅ Real-time data (chat messages, live updates)

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StreamBuilder<List<Message>>(
  stream: messagesStream,
  builder: (context, snapshot) => ListView(...),
)

ChangeNotifier

✅ Complex state with multiple properties (cart, user profile)

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AnimatedBuilder(
  animation: cart,
  builder: (context, child) => Text('${cart.items.length} items'),
)

Full App Example (No External State Management)

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import 'package:flutter/material.dart';

void main() => runApp(MyApp());

// InheritedWidget for app-wide state
class AppState extends InheritedWidget {
  final ValueNotifier<List<String>> todos;

  AppState({required this.todos, required Widget child}) : super(child: child);

  static AppState of(BuildContext context) {
    return context.dependOnInheritedWidgetOfExactType<AppState>()!;
  }

  @override
  bool updateShouldNotify(AppState oldWidget) => false;
}

class MyApp extends StatelessWidget {
  final ValueNotifier<List<String>> todos = ValueNotifier([]);

  @override
  Widget build(BuildContext context) {
    return AppState(
      todos: todos,
      child: MaterialApp(
        home: TodoScreen(),
      ),
    );
  }
}

class TodoScreen extends StatelessWidget {
  final TextEditingController _controller = TextEditingController();

  @override
  Widget build(BuildContext context) {
    final appState = AppState.of(context);

    return Scaffold(
      appBar: AppBar(title: Text('Todos')),
      body: Column(
        children: [
          Padding(
            padding: EdgeInsets.all(16),
            child: TextField(
              controller: _controller,
              onSubmitted: (value) {
                if (value.isNotEmpty) {
                  appState.todos.value = [...appState.todos.value, value];
                  _controller.clear();
                }
              },
              decoration: InputDecoration(labelText: 'Add Todo'),
            ),
          ),
          Expanded(
            child: ValueListenableBuilder<List<String>>(
              valueListenable: appState.todos,
              builder: (context, todos, child) {
                return ListView.builder(
                  itemCount: todos.length,
                  itemBuilder: (context, index) {
                    return ListTile(
                      title: Text(todos[index]),
                      trailing: IconButton(
                        icon: Icon(Icons.delete),
                        onPressed: () {
                          final newTodos = List<String>.from(todos);
                          newTodos.removeAt(index);
                          appState.todos.value = newTodos;
                        },
                      ),
                    );
                  },
                );
              },
            ),
          ),
        ],
      ),
    );
  }
}

Best Practices

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// ✅ Use setState for local state
setState(() { _counter++; });

// ✅ Use InheritedWidget for app-wide state
final appState = AppState.of(context);

// ✅ Dispose ValueNotifier and StreamController
@override
void dispose() {
  _notifier.dispose();
  _controller.close();
  super.dispose();
}

// ❌ Don't overuse setState (causes unnecessary rebuilds)
// Extract StatefulWidgets for isolated state

// ❌ Don't use InheritedWidget for frequently changing state
// Use ValueNotifier or ChangeNotifier instead

Summary

Key Takeaway: You can build full Flutter apps without BLoC, Riverpod, or Provider using native Flutter state management techniques.

Learn more: Flutter State Management