React useState Example

App.js

import {useState} from 'react';

const App = () => {
  const [counter, setCounter] = useState(0);

  const incrementHandler = () => setCounter(counter + 1);
  const decrementHandler = () => setCounter(counter - 1);

  return (
      <>
        <Button onClick={decrementHandler} text='Decrement'/>
        <Button onClick={incrementHandler} text='Increment'/>
        <Display counter={counter}/>
      </>
  );
};

const Display = ({counter}) => <div>{counter}</div>;
const Button = ({onClick, text}) => <button onClick={onClick}>{text}</button>;

export default App;