React router v4 history.push() 组件不更新啊，代码如下,ui不更新啊

#1 
import React from 'react'
import {
  BrowserRouter as Router,
  Route,
  Link,
  Switch,
  BrowserRouter
} from 'react-router-dom'
import {unmountComponentAtNode, findDOMNode} from 'react-dom';
import createBrowserHistory from 'history/createBrowserHistory';
const history = createBrowserHistory();

const BasicExample = () => (
  
    
  <BrowserRouter history={history}>
    <div>
      <ul>
        <li><Link to="/">Home</Link></li>
        <li><Link to="/about">About</Link></li>
        
        <li><Link to="/not_find">404</Link></li>
      </ul>

      <hr/>
      <div id="oops">
        <Switch>
          <Route exact path="/" component={Home}/>
          <Route path="/about" component={About}/>
          
          <Route path="/not_find" component={NotFound}/>
        </Switch>
      </div>
    </div>
  
  </BrowserRouter>
  
  
)

const Home = () => (
  <div>
    <h2>Home</h2>
  </div>
)

const About = () => (
  <div>
    <h2>About</h2>
  </div>
)



class NotFound extends React.Component {
	constructor() {
		super();
	}
  handleSubmit(e) {
    const div = document.createElement('div')
    const location = {
      pathname: '/about',
      state: { fromDashboard: true }
    };
    history.push(location)
    
  }
  componentDidMount() {
    //alert(10)
  }
  componentWillUnmount() {
       
  }
  render() {
        return (<div ref="wassup" onClick = {this.handleSubmit.bind(this)} className = "app-notfind-page">hi,404<div ref = 'oops' className="s1">111</div></div>)
    }
}

export default BasicExample
#2

this.props.history.push()

#3

import {
BrowserRouter as Router,
Route,
Link,
Switch,
BrowserRouter
} from ‘react-router-dom’
将上面的 BrowserRouter as Router改成Router，因为BrowserRouter内置了history，而Router是支持传入history