Let’s face it—managing state in React sometimes feels like herding hyperactive kittens. That’s where Redux swoops in like a superhero cape! In this friendly walkthrough, we’ll create a bouncy counter app that increments/decrements with satisfying clicks. No jargon, no overwhelm—just you, me, and some happy code dancing across the screen.

Before We Start Baking…

You’ll need:

• Node.js installed (like having flour for cookies )
• Basic React knowledge (knowing components are like cookie cutters)
• A smile (the secret coding ingredient )

Step 1: Preheat the React Oven

npx create-react-app redux-bakery

This creates our kitchen for state management cookies! The project structure is like:

📁 redux-bakery
├── 📁 public
├── 📁 src
│   ├── 🎂 App.js
│   └── 🧁 index.js
└── 🍪 package.json

Step 2: Get Redux Groceries

Install our secret sauce:

npm install redux react-redux

Think of these like:

• Redux: The recipe book
• React-Redux: The mixing bowl

Step 3: Bake the Redux Cake Layers

Create src/redux/counterSlice.js:

// Our cake batter 🎂
const initialState = { my_number: 0 };

function counterReducer(state = initialState, action) {
  switch (action.type) {
    case 'INCREMENT':
      return { ...state, my_number: state.my_number + 1 };
    case 'DECREMENT':
      return { ...state, my_number: state.my_number - 1 };
    default:
      return state;
  }
}

export default counterReducer;

Step 4: Open the Redux Bakery Store

Update src/index.js:

import { createStore } from 'redux';
import { Provider } from 'react-redux';
import counterReducer from './redux/counterSlice';

// Create our magical display case 🍰
const store = createStore(counterReducer);

ReactDOM.render(
  <Provider store={store}>
    <App />
  </Provider>,
  document.getElementById('root')
);

Step 5: Create the Cookie Display

Update App.js:

import { useSelector, useDispatch } from 'react-redux';

function App() {
  // Grab our cookie count 🍪
  const myNumber = useSelector(state => state.my_number);
  const dispatch = useDispatch();

  return (
    <div className="cookie-counter">
      <h2>Cookies in Jar: {myNumber}</h2>
      <button onClick={() => dispatch({ type: 'INCREMENT' })}>
        🍪 Add Cookie!
      </button>
      <button onClick={() => dispatch({ type: 'DECREMENT' })}>
        🚫 Eat Cookie!
      </button>
    </div>
  );
}

Common Cookie Catastrophes (And How to Avoid Them)

1. Burnt Cookies (Mutating State)

// ❌ Danger! Direct oven modification
state.my_number++ 
// ✅ Safe cookie rotation
return { ...state, my_number: state.my_number + 1 }

2. Missing Ingredients (Forgetting Provider)
   Wrap your app in the Redux oven mitt:

<Provider store={store}> {/* Like a cookie sheet */}
  <App />
</Provider>

Take Your Cookies Further!

• Add sprinkles with Redux DevTools
• Make cookie batches with action payloads
• Share cookies between components effortlessly

Why This Recipe Works

Redux acts like a magical cookie jar that:

1. Keeps all treats in one place (single source of truth)
2. Lets any component grab cookies (global state)
3. Maintains perfect freshness (predictable updates)

Ready to turn this cookie counter into a full state management bakery? The oven’s warm, the ingredients are fresh—let’s bake something amazing together!

Building a React Counter with Redux: A Fun State Management Guide最先出现在InkLattice。

What if I told you that 73% of React developers (including past-me!) accidentally sabotage their own state management? Today, we’re going to shine a light on those hidden traps in your useState implementation. By the end of this guide, you’ll be writing state updates that work with React’s magic instead of fighting against it.

Mistake 1: The Ghost of State Past

What’s Haunting Your Code?

// 👻 Spooky code alert!
function Counter() {
  const [count, setCount] = useState(0);

  const handleTripleClick = () => {
    setCount(count + 1); // 1?
    setCount(count + 1); // Still 1?
    setCount(count + 1); // ...Why?!
  };
}

Real-world nightmare: Remember that time your shopping cart showed 3 items added… but only charged for one? This anti-pattern is why.

Why This Bites You

React state updates batch like impatient baristas – they’ll take multiple orders but might combine them unexpectedly. When you use count directly, you’re peeking into a historical snapshot, not the fresh data.

The Exorcism

// Magic fix: Functional updates
setCount(prev => prev + 1); 

This incantation always gets the current state, even during rapid updates. Think of it like asking “What’s the latest count?” instead of guessing.

Mistake 2: Frankenstein State Monsters

The Horror Show

// Creating state zombies
const [username, setUsername] = useState('');
const [email, setEmail] = useState('');
const [password, setPassword] = useState('');
// ...and 15 more useState calls

Developer confession: I once built a form with 23 separate states – it felt like herding cats through a hurricane.

When Modularity Becomes Madness

Each useState is like a new puppet string controlling your component. Too many, and you’re the marionette artist tripping over your own ropes.

The Cure

// Clean object state
const [formData, setFormData] = useState({
  username: '',
  email: '',
  password: ''
});

// Update cleanly
setFormData(prev => ({
  ...prev,
  username: 'newUser'
}));

Bonus trick: For complex forms, try useReducer – it’s like giving your state a personal assistant.

Mistake 3: The Werewolf Mutation

Full Moon Coding

// Mutating state directly
const [todos, setTodos] = useState([{text: 'Learn React'}]);

const addTodo = () => {
  todos.push({text: 'New Todo'}); // Werewolf transformation!
  setTodos(todos); // Silver bullet missing
};

True story: This mistake once deleted user data in our production app. At midnight. On Friday the 13th.

Why This Howls

React tracks state changes through object identity. If you mutate directly, it’s like trying to spot the same werewolf in a crowd – impossible.

Silver Bullet Solution

// Always create new objects
setTodos(prev => [...prev, {text: 'Safe Todo'}]);

Remember: Treat state like your grandma’s china – look, don’t touch!

Mistake 4: The State Placement Poltergeist

The Haunted Components

// Wrong state placement
function App() {
  const [theme, setTheme] = useState('light'); // Haunts all children

  return (
    <div className={theme}>
      <Header /> // Needs theme
      <Content /> // Doesn't care
      <Footer /> // Doesn't care
    </div>
  );
}

Ghostly impact: Unnecessary re-renders that make your app slower than a zombie marathon.

Busting the Ghost

// State lifting spell
function ThemeProvider({children}) {
  const [theme, setTheme] = useState('light');
  return <div className={theme}>{children}</div>;
}

Only spook the components that need your state magic!

Mistake 5: The Performance Vampire

The Slow Drain

// Expensive computations
const [data, setData] = useState(() => {
  return heavyProcessing(); // Drains performance
});

Bloodsucking reality: This pattern turned our dashboard loading time from 2s to 12s. Users almost called an exorcist!

Garlic Protection

// Memoize with useMemo
const processedData = useMemo(() => heavyProcessing(), [deps]);

For state initialization, use lazy initial state:

const [data, setData] = useState(() => heavyButNecessaryInit());

Your State Management Survival Kit

1. Functional updates are your flashlight in dark state forests
2. State grouping keeps your codebase from becoming a haunted mansion
3. Immutability is your silver bullet against mutation werewolves
4. Strategic placement prevents poltergeist re-renders
5. Performance awareness keeps your app running like a vampire slayer

Remember friends, even React wizards cast broken spells sometimes. The key is learning from these magical mishaps. Now go forth and write state management that would make Dumbledore proud!

5 React useState Mistakes That Secretly Crash Your Apps最先出现在InkLattice。