我正在使用 React-Routerv4，当我使用登录表单登录时，我isUser使用函数将应用组件状态值从子组件登录设置为 true，登录后setUserLogin我可以在控制台中正确调试。我还指定了，如果我迁移到/login路径，它会检查isUser要迁移到的状态值，/home page如果用户已经登录（isUser是true）。但是该值现在自动更改为默认值false，当我/login在浏览器中输入并显示登录页面而不是主页时。我是 React 的新手，所以我在这里遗漏了什么吗？这是代码片段：

import React from 'react';
import ReactDom from 'react-dom';
import 'materialize-css/bin/materialize.css'
import 'materialize-css/bin/materialize.js';
import {BrowserRouter as Router, Route , Redirect} from 'react-router-dom';
import {LoginForm} from './components/login';
import {Home} from './components/home';
import {Main} from './components/main';
import {Room} from './components/room';
import "materialize-css";
import 'materialize-css/js/toasts';


class App extends React.Component {
    constructor(props){
        super(props);
        this.state={
            isUser : false
        }
        this.setUserLogin = this.setUserLogin.bind(this);
    }
    setUserLogin(){
        this.setState({isUser:true});
    }
    render() {
        return <Router>
            <div>
                <Route exact path="/" component={Home}/>
                <Route path="/login" render={(props)=>(
                    this.state.isUser ? <Redirect to="/home" /> : <LoginForm history={props.history} setUserLogin = {this.setUserLogin}/>
                )} />
                <Route path="/home" component={Main}/>
                <Route path="/room" component={Room}/>
            </div>
        </Router>
    };
}
ReactDom.render(<App/>, document.getElementById('app'));