App.js 引入了 一個子組件 SnackbarExampleSimple

import React from 'react';
import ReactDOM from 'react-dom';
import SnackbarExampleSimple from './Header'


  const App = () => (

    <div>
       {/* <Header/> */}
       <SnackbarExampleSimple/>
    </div>
   );
export default App;

Header.js,里面代碼基本上是復制的官網(wǎng)實例

import React from 'react';
// import ReactDOM from 'react-dom';
// import './css/header.css';

import Snackbar from 'material-ui/Snackbar';
import RaisedButton from 'material-ui/RaisedButton';

export default class SnackbarExampleSimple extends React.Component {

  constructor(props) {
    super(props);
    this.state = {
      open: false,
    };
  }

  handleClick = () => {
    this.setState({
      open: true,
    });
  };

  handleRequestClose = () => {
    this.setState({
      open: false,
    });
  };

  render() {
    return (
      <div>
        <RaisedButton
          onClick={this.handleClick}
          label="Add to my calendar"
        />
        <Snackbar
          open={this.state.open}
          message="Event added to your calendar"
          autoHideDuration={4000}
          onRequestClose={this.handleRequestClose}
        />
      </div>
    );
  }
}

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