counter.html

web-cheat/redux/counter.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Hello World</title>
<!-- https://github.com/reduxjs/redux/tree/0c90666a022d943103c8805bc3dba8e9f7a87d3d/examples/counter -->
<script src="https://unpkg.com/react@17/umd/react.development.js"></script>
<script src="https://unpkg.com/react-dom@17/umd/react-dom.development.js"></script>
<script src="https://unpkg.com/@babel/standalone@7.14.7/babel.min.js"></script>
<script src="https://unpkg.com/redux@4.1.0/dist/redux.js"></script>
</head>
<body>
<div id="root"></div>
<script type="text/babel">
class Main extends React.Component {
  constructor(props) {
    super(props);
    this.incrementAsync = this.incrementAsync.bind(this);
    this.incrementIfOdd = this.incrementIfOdd.bind(this);
  }

  incrementIfOdd() {
    if (this.props.value % 2 !== 0) {
      this.props.onIncrement()
    }
  }

  incrementAsync() {
    setTimeout(this.props.onIncrement, 1000)
  }

  render() {
    const { value, onIncrement, onDecrement } = this.props
    return (
      <p>
        Clicked: {value} times
        {' '}
        <button onClick={onIncrement}>
          +
        </button>
        {' '}
        <button onClick={onDecrement}>
          -
        </button>
        {' '}
        <button onClick={this.incrementIfOdd}>
          Increment if odd
        </button>
        {' '}
        <button onClick={this.incrementAsync}>
          Increment async
        </button>
      </p>
    )
  }
}

const counter = (state = 0, action) => {
  switch (action.type) {
    case 'INCREMENT':
      return state + 1
    case 'DECREMENT':
      return state - 1
    default:
      return state
  }
}
const store = Redux.createStore(counter)
const render = () => ReactDOM.render(
  <Main
    value={store.getState()}
    onIncrement={() => store.dispatch({ type: 'INCREMENT' })}
    onDecrement={() => store.dispatch({ type: 'DECREMENT' })}
  />,
  document.getElementById('root')
)
render()
store.subscribe(render)
</script>
</body>
</html>