我正在尝试使用ReactJS创建一个简单的Webapp，我想使用NavbarReact-Bootstrap提供的。

我创建了一个Navigation.js文件，其中包含一个类，Navigation用于将Navbar和和路由与App.js文件分开。但是，这两个部分似乎都不起作用。当我加载页面时，它只是空的，没有导航栏。谁能发现一个错误？

Navigation.js：

import React, { Component } from 'react';
import { Navbar, Nav, Form, FormControl, Button, NavItem } from 'react-bootstrap';
import { Switch, Route } from 'react-router-dom';
import { Home } from './Page';

class Navigation extends Component {
    render() {
        return (
            <div>
                <div>
                    <Navbar>
                        <Navbar.Brand href="/">React-Bootstrap</Navbar.Brand>
                        <Navbar.Collapse>
                            <Nav className="mr-auto">
                                <NavItem eventkey={1} href="/">
                                    <Nav.Link href="/">Home</Nav.Link>
                                </NavItem>
                            </Nav>
                            <Form inline>
                                <FormControl type="text" placeholder="Search" className="mr-sm-2" />
                                <Button variant="outline-success">Search</Button>
                            </Form>
                        </Navbar.Collapse>
                    </Navbar>
                </div>
                <div>
                    <Switch>
                        <Route exact path='/' component={Home} />
                        <Route render={function () {
                            return <p>Not found</p>
                        }} />
                    </Switch>
                </div>
            </div>
        );
    }
}

export default Navigation;

App.js：

import React, { Component } from 'react';
import Navigation from './components/routing/Navigation';



class App extends Component {
  render() {
    return (
      <div id="App">
        <Navigation />
      </div>
    );
  }
}

export default App;

我尝试使用已经NavItem包含的LinkContainerfrom react-router-bootstrap，这导致了相同的结果。

为了完整性，Page.js：

import React, { Component } from 'react';
import { Link } from 'react-router-dom';

export const Page = ({ title }) => (
    <div className="App">
      <div className="App-header">
        <h2>{title}</h2>
      </div>
      <p className="App-intro">
        This is the {title} page.
      </p>
      <p>
        <Link to="/">Home</Link>
      </p>
      <p>
        <Link to="/about">About</Link>
      </p>
      <p>
        <Link to="/settings">Settings</Link>
      </p>
    </div>
);


export const About = (props) => (
    <Page title="About"/>
);

export  const Settings = (props) => (
    <Page title="Settings"/>
);

export const Home = (props) => (
    <Page title="Home"/>
);