组件不会在路由更改时重新呈现 - React HashRouter

Question

I've got a problem with react and react-router . When I click on a link (in my example contact in Footer.js ), the url changes, but the desired component Location is not shown. When I refresh the site then, the correct component is displayed.

App.js:

import React, { Component } from 'react';
import { BrowserRouter as Router, HashRouter, Route, Link } from 'react-router-dom';
import 'bootstrap/dist/css/bootstrap.css';
import Footer from './Footer.js';
import Navigation from './Navigation.js';
import Background from './Background.js';
import Home from './Home.js';
import Products from './Products.js';
import Industries from './Industries.js';
import Partner from './Partner.js';
import Location from './Location.js';
import MeetUs from './MeetUs.js';
import ScrollUp from './ScrollUp.js';
import Divider from './Divider.js';
import Country from './Country.js';
import Language from './Language.js';
import Waypoint from 'react-waypoint';
import $ from "jquery";

class App extends Component {

  constructor(props) {
    super(props);
    this.state = {
      currentLanguage: 'en',
      currentBU: '',
      currentIndustry: '',
      showMainProductGroups: false,
      currentCountry: 'group',
      countryObject: Country['group'],
      contacts: [],
      mainProductGroups: [],
    };
  }

  handleCountryChange() {
  //...
  }

  handleLanguageChange() {
  //...
  }

  handleBUChange() {
  //...
  }

  render() {
    const routes = [
      { 
        path: '/',
        exact: true,
        components: () => 
          <div>
            <Home key="home" currentLanguage={this.state.currentLanguage} />
          </div>,
      },
      { 
        path: '/contact',
        exact: true,
        components: () => <Location key="locations" currentLanguage={this.state.currentLanguage} country={this.state.countryObject} contacts= {this.state.contacts} onCountryChange={this.handleCountryChange.bind(this)} />
      },
    ]
    return (
      <HashRouter>
    <div>
      <Background />
      <div id="wrap">
        <div id="main" className="container clear-top marginBottom50px">
            <div id="content">
              <Navigation key="navBar" currentLanguage={this.state.currentLanguage} onLanguageChange={this.handleLanguageChange.bind(this)} onBUChange={this.handleBUChange.bind(this)} onCountryChange={this.handleCountryChange.bind(this)} />
              {
                routes.map((route, index) => (
                <Route key={index} path={route.path} exact={route.exact} component={route.components} />
              ))
              }
            </div>
        </div>
      </div>
      <Footer key="footer" currentLanguage={this.state.currentLanguage} />
      <ScrollUp key="scrollUp" />
    </div>
  </HashRouter>
    );
  }
}

export default App;

Home.js:

import React, { Component } from 'react';
import $ from "jquery";
import {  Link } from 'react-router-dom';
import {withRouter} from 'react-router';
import Language from './Language.js';
import locations from './locations.jpg';
import locationLegend from './locationLegend.jpg';
require('bootstrap')

class Home extends Component {
    constructor(props) {
        super(props);
        this.state = {
        };
    }

    render() {
        return (
            <div className="container marginTop50px marginBottom50px area">
                <div className="row">
                    <div className="col-12 text-center animDelay2 fadeInDown animated">
                        <h1>International Distribution of Specialty Chemicals</h1>
                    </div>
                </div>
                <div className="row marginTop25px">
                    <div className="col-12 text-center animDelay2 fadeInUp animated">
                        {Language[this.props.currentLanguage].homeStartText}
                    </div>
                </div>
                <div className="row marginTop25px">
                    <div className="col-12 text-center">
                        <img src={locations} className="img-fluid" alt="Locations" />
                    </div>
                </div>
                <div className="row marginTop25px">
                    <div className="col-12 text-center">
                        <img src={locationLegend} className="img-fluid" alt="Locations" />
                    </div>
                </div>
            </div>
        );
    }
}

export default withRouter(Home);

Location.js:

import React, { Component } from 'react';
import $ from "jquery";
import { Link } from 'react-router-dom';
import Language from './Language.js';
import Country from './Country.js';
import ContactPerson from './ContactPerson.js';
import locations from './locations.png';
import phone from './phoneBlack.svg';
import fax from './faxBlack.svg';
import email from './emailBlack.svg';
import {withRouter} from 'react-router';
require('bootstrap');

class Location extends Component {
    constructor(props) {
        super(props);
        this.state = {
        };
    }

    componentDidUpdate(prevProps, prevState, snapshot) {
        console.log('Country change:' + this.props.country.key);
        $('#selectCountry').val(this.props.country.key); //name['en']
    }

    onCountryChange() {
        let countryName = this.refs.country.value;
        this.props.onCountryChange(countryName);
    }

    render() {
        return (
            <div className="container marginTop50px marginBottom50px area" id="locations">
                <div className="row">
                    <div className="col-12 text-center">
                        <h2>{Language[this.props.currentLanguage].locations}</h2>
                    </div>
                </div>
                <div className="row marginTop25px">
                    <div className="col-12 text-center">
                        <div className="form-group">
                            <select id="selectCountry" className="form-control" ref="country" onChange={this.onCountryChange.bind(this)}>
                                <option defaultValue>{Language[this.props.currentLanguage].selectLocation.toUpperCase()}</option>
                                {
                                    Object.keys(Country).map((countryKey) => {
                                        const country = Country[countryKey];
                                        return (
                                            <option value={countryKey} key={"loc" + countryKey}>{country.name[this.props.currentLanguage].toUpperCase()}</option>
                                        );
                                    })
                                }
                            </select>
                        </div>
                    </div>
                </div>
                <div className="row marginTop25px">
                    <div className="col-12 text-center">
                        {this.props.country.name[this.props.currentLanguage].toUpperCase()}
                        <br />
                        <address>
                            <span dangerouslySetInnerHTML={{__html: this.props.country.address}}></span>
                            <br />
                            <br />
                            <img src={phone} alt="Anrufen" className="phoneMain"></img><span> </span>
                            <a href={this.props.country.phoneHTML}>{this.props.country.phone}</a>
                            <br />
                            <img src={fax} alt="Fax" className="phoneMain"></img><span> </span>
                            <a href={this.props.country.faxHTML}>{this.props.country.fax}</a>
                            <br />
                            <img src={email} alt="Email" className="emailMain"></img><span> </span>
                            <a href={"mailto://" + this.props.country.email}>{this.props.country.email}</a>
                        </address>
                    </div>
                </div>
                <div className="row marginTop25px">
                    <div className="col-12 text-center">
                        {Language[this.props.currentLanguage].vatRegistrationNumber + ": " + this.props.country.vatNo}
                        <br />
                        {Language[this.props.currentLanguage].registrationOffice + ": "}
                        <span dangerouslySetInnerHTML={{__html: this.props.country.registrationOffice}}></span>
                    </div>
                </div>
                <div className="row marginTop50px">
                    <div className="col-12 text-center">
                        <h3>{Language[this.props.currentLanguage].contact}</h3>
                    </div>
                </div>
                <div className="row">

                        {
                            this.props.contacts.map((contact) => {
                                return (
                                    <div className="col-12 col-sm-12 col-md-12 col-lg-6 text-center">
                                        <ContactPerson contact={contact} key={"contact" + contact.id} />
                                    </div>
                                );
                            })
                        }
                </div>
            </div>
        );
    }
}

export default withRouter(Location);

Footer.js:

import React, { Component } from 'react';
import $ from "jquery";
import {  Link } from 'react-router-dom';
import {withRouter} from 'react-router';
import Language from './Language.js';
import phone from './phoneWhite.svg';
import fax from './faxWhite.svg';
require('bootstrap');

class Footer extends Component {
    constructor(props) {
        super(props);
        this.state = {
        };
    }

    render() {
        return (
            <footer className="footer">
                <div className="container-fluid borderTop1px footerLayout">
                    <div className="row">
                        <div className="col-3">
                            <address>
                                <small>
                                    Some text
                                </small>
                            </address>
                        </div>
                        <div className="col-6 text-center">
                            <div className="row">
                                <div className="col-12 col-sm-12 col-md-12 col-lg-3 text-center">
                                    <a href="https://download.group.com" className="nav-link footerLink" target="_self"><small>{Language[this.props.currentLanguage].download}</small></a>
                                </div>
                                <div className="col-12 col-sm-12 col-md-12 col-lg-3 text-center">
                                    <Link to="/imprint" className="nav-link footerLink"><small>{Language[this.props.currentLanguage].imprint}</small></Link>
                                </div>
                                <div className="col-12 col-sm-12 col-md-12 col-lg-3 text-center">
                                    <Link to="/contact" className="nav-link footerLink"><small>{Language[this.props.currentLanguage].contact}</small></Link>
                                </div>
                                <div className="col-12 col-sm-12 col-md-12 col-lg-3 text-center">
                                    <Link to="/termsAndConditions" className="nav-link footerLink"><small>{Language[this.props.currentLanguage].termsAndConditions}</small></Link>
                                </div>
                            </div>
                        </div>
                        <div className="col-3">
                            <ul className="list-inline">
                                <li>
                                    <img src={phone} alt="Anrufen" className="phone"></img> <small><a className="footerLink" href="tel:+49">+49</a></small>
                                </li>
                                <li>
                                    <img src={fax} alt="Fax" className="phone"></img> <small><a className="footerLink" href="tel:+49">+49</a></small>
                                </li>
                            </ul>
                        </div>
                    </div>
                </div>
            </footer>
        );
    }
}

export default withRouter(Footer);

What I'm doing wrong? Why it is not working, when I click on a link?

Answer 1

Got it working now. I needed to change <HashRouter> to <Router> . Then it works fine.

UPDATE: This solution solves the problem, but then there is a different problem: When I have navigated and refresh the page, then an error (404) is thrown, because there is of course no such a page on the server.

I need to get the HashRouter work.

Answer 2

When you declare your routes in App.js , you should pass the props to the component:

components: props => <Location {...props} <insert other props> />

You should stick to the <Router> solution as having unnecessary hash in the url is ugly.

When I have navigated and refresh the page, then an error (404) is thrown, because there is of course no such a page on the server.

To resolve this, you need to set up a redirect to redirect all requests to the base url for the React app to handle (the url displayed will be preserved).

On Netlify , you can create a _redirects file in your public folder with the content:

/*  /index.html  200

On AWS S3, the redirect rules can be set in S3 or CloudFront, see the answers here .

For Google Cloud bucket, see this .

For Github pages, see this .

Answer 3

In your Route component you use component prop to pass the Location component (instead of render or children props available on Route) the router uses React.createElement to create a new React element from the given component. That means if you provide an inline function to the component prop, you would create a new component every render. This results in the existing component unmounting and the new component mounting instead of just updating the existing component. When using an inline function for inline rendering, use the render or the children prop.However in your case it seems you are using it for no reason so you should just pass the component and not an inline function that returns it like so :

const routes = [
      { 
        path: '/',
        exact: true,
        components: <Home key="home" currentLanguage={this.state.currentLanguage}/>

      },
      { 
        path: '/contact',
        exact: true,
        components: <Location key="locations" currentLanguage={this.state.currentLanguage} country={this.state.countryObject} contacts= {this.state.contacts} onCountryChange={this.handleCountryChange.bind(this)} />
      },
    ]

Answer 4

Make your routes use Component as below

import {IndexRoute, Route} from 'react-router';

 <Route component={App}>
    <Route path='/locations' component={LocationComponent}/>
 </Route>

This is what I am doing in my current project without using HashRouter.

Currently, When you do

<Route key={index} path={route.path} exact={route.exact} component={route.components} />

I don't think {route.components} treats it as a component.

Answer 5

Could be a problem with withRouter() .

Have you seen this? https://github.com/ReactTraining/react-router/issues/5037