React hooks and context api localstorage on refresh - javascript

In my SPA, I am utilizing react hooks and context API. I need to persist the current state of the component view rendered using the context API so that I can implement the global component conditional rendering through the application.
I have two views on a single dashboard page: overview & detail. The button triggers the global state change and the view should be fixed on the state value even on page refresh.
Here's my code snippets:
AppRoutes file
import React, { useState } from "react";
import { Router, Route, Switch } from "react-router-dom";
import history from "../utils/history";
import { PyramidProvider } from "../context/pyramidContext";
import Dashboard from "../pages/dashboard/Dashboard";
const AppRoutes = () => {
return (
<div>
<React.Suspense fallback={<span>Loading...</span>}>
<Router history={history}>
<Switch>
<PyramidProvider>
<Route path="/" component={Dashboard} />
</PyramidProvider>
</Switch>
</Router>
</React.Suspense>
</div>
);
};
export default AppRoutes;
Dashboard page
import React, { useState, useEffect, useContext } from "react";
import { PyramidContext } from "../../context/pyramidContext";
import PyramidDetail from "../../components/pyramidUI/pyramidDetail";
import PyramidOverview from "../../components/pyramidUI/pyramidOverview";
const Dashboard = (props) => {
const { info, setInfo } = useContext(PyramidContext);
return (
<React.Fragment>
{info.uiname === "overview" ? <PyramidOverview /> : <PyramidDetail />}
</React.Fragment>
);
};
export default Dashboard;
Overview component
import React, { useState, useContext } from "react";
import { PyramidContext } from "../../context/pyramidContext";
const Overview = (props) => {
const { info, setInfo } = useContext(PyramidContext);
return (
<div className="d-flex flex-column dashboard_wrap">
<main>
<div className="d-flex">
<button
onClick={() => setInfo({ uiname: "detail", pyramidvalue: 1 })}
>
change view
</button>
</div>
</main>
</div>
);
};
export default Overview;
Detail component
import React, { useContext } from "react";
import { PyramidContext } from "../../context/pyramidContext";
// import axios from "axios";
const Detail = (props) => {
const { info, setInfo } = useContext(PyramidContext);
return (
<div className="d-flex flex-column dashboard_wrap">
<h2>Detail View</h2>
<div>
<button
type="button"
onClick={() => setInfo({ uiname: "overview", pyramidvalue: 0 })}
>
Back
</button>
</div>
</div>
);
};
export default Detail;
Context File
import React, { createContext, useEffect, useReducer } from "react";
let reducer = (info, newInfo) => {
return { ...info, ...newInfo };
};
const initialState = {
uiname: "overview",
pyramidvalue: 0,
};
const localState = JSON.parse(localStorage.getItem("pyramidcontent"));
const PyramidContext = createContext();
function PyramidProvider(props) {
const [info, setInfo] = useReducer(reducer, initialState || localState);
useEffect(() => {
localStorage.setItem("pyramidcontent", JSON.stringify(info));
}, [info]);
return (
<PyramidContext.Provider
value={{
info,
setInfo,
}}
>
{props.children}
</PyramidContext.Provider>
);
}
export { PyramidContext, PyramidProvider };
I click the button to render a detail view and soon as the page is refreshed, the component changes its view to overview instead of sticking around to detail. I checked the local storage values, and it is being updated properly, but still, the component view does not persist as per the value.
I am unable to understand where I am doing wrong, any help to resolve this issue, please? Thanks in advance.

You're never using the value of localStage in your info state,
you should replace your code with:
const [info, setInfo] = useReducer(reducer, localState || initialState);

Related

Why does optional chaining allows rendering when fetching data through useEffect in an app that uses context?

I'm new to the webdev world and want to learn ReactJS. I followed a tutorial I found on YouTube made by Traversy where he makes a task tracker and now I want to make some changes to it to learn and practice some more.
I want to use context for the appointments (originally named tasks in the tutorial), add a calendar with react-calendar and use react-router-dom.
I got stuck for a while trying to make the list render, because it only rendered "empty". Later on found this post with a similar issue to mine: Only run a useEffect fetch after first useEffect fetch has fired and setUser in context
I changed bits of my code based on that post and now it does render the appointment list, but I don't know why it didn't work before and I'm unsure on why it does work now. I don't even know if I'm using context correctly or just prop-drilling. Help would be greatly appreciated. Thank you.
Also, sorry if my code is a mess, I'm new at this.
App.js
import { createContext, useState, useEffect } from "react";
import Dashboard from "./views/Dashboard";
import './App.css';
import { BrowserRouter as Router, Route, Routes} from "react-router-dom";
import AddAppointmentForm from "./views/AddAppointmentForm";
export const AppContext = createContext();
export const AppUpdateContext = createContext();
function App() {
const [appointments, setAppointments] = useState([])
const updateAppointments = (apptList) => {
setAppointments(apptList)
}
return (
<AppContext.Provider value={ appointments }>
<AppUpdateContext.Provider value={ updateAppointments }>
<Router>
<Routes>
<Route path="/" element={<Dashboard appointments={appointments} />} />
{/* <Route path="/add" element={<AddAppointmentForm />} /> TBA */}
</Routes>
</Router>
</AppUpdateContext.Provider>
</AppContext.Provider>
);
}
export default App;
Dashboard.js
import { useEffect, useContext} from "react";
import { AppContext } from "../App";
import { AppUpdateContext } from "../App";
import AppointmentList from "../components/AppointmentList";
import Header from "../components/Header";
// function Dashboard() { // this is how it used to be
function Dashboard(props) {
const appointments = useContext(AppContext)
const setAppointments = useContext(AppUpdateContext)
const fetchAppointmentList = async () => {
const res = await fetch("http://localhost:5000/appointments");
const data = await res.json();
return data;
}
useEffect(() => {
const getAppointments = async () => {
const appointmentsFromServer = await fetchAppointmentList();
setAppointments(appointmentsFromServer);
}
getAppointments();
console.log("ñññññ",appointments)
}, []);
console.log("aagh",appointments)
return (
<div style={dashboardStyle}>
<Header />
{/* {appointments.lenght>0 ? (<AppointmentList />) : <p>empty</p>} this is how it used to be */}
<AppointmentList appointments={props?.appointments}/>
</div>
);
}
const dashboardStyle = {
maxWidth: "31.25rem",
overflow: "auto",
minHeight: "18.75rem",
border: "1px solid steelblue",
margin: "1.875rem auto",
padding: ".5rem",
boxSizing: "border-box",
}
export default Dashboard;
AppointmentList.js
import Appointment from "./Appointment";
import { AppContext } from "../App";
import { useContext } from "react";
function AppointmentList({ appointments }) {
// function AppointmentList() { // this is how it used to be
// const { appointments, setAppointments } = useContext(AppContext)
console.log("appList",appointments) // this is how it used to be
return (
<>
{
appointments.map(appt => (
<Appointment key={appt.id} appointment={appt} />
))
}
</>
);
}
export default AppointmentList;
Why does optional chaining allows rendering when fetching data through
useEffect in an app that uses context?
<AppointmentList appointments={props?.appointments}/>
It allows rendering by preventing accidental accesses into potentially null or undefined objects. The only way props could be undefined though is if you just simply don't declare it, i.e. const Dashboard = () => {.... vs const Dashboard = (props) => {.....
You are drilling the appointments state through props. AppointmentList can use the AppContext context to access the appointments state, while Dashboard can use the AppUpdateContext context to update the appointments state.
App
function App() {
const [appointments, setAppointments] = useState([]);
const updateAppointments = (apptList) => {
setAppointments(apptList);
};
return (
<AppContext.Provider value={{ appointments }}> // <-- need object here
<AppUpdateContext.Provider value={{ updateAppointments }}> // <-- and here
<Router>
<Routes>
<Route path="/" element={<Dashboard />} /> // <-- don't pass props
</Routes>
</Router>
</AppUpdateContext.Provider>
</AppContext.Provider>
);
}
Dashboard
function Dashboard() { // <-- no props
const { updateAppointments } = useContext(AppUpdateContext); // <-- access from context
const fetchAppointmentList = async () => {
const res = await fetch("http://localhost:5000/appointments");
const data = await res.json();
return data;
};
useEffect(() => {
const getAppointments = async () => {
const appointmentsFromServer = await fetchAppointmentList();
updateAppointments(appointmentsFromServer);
}
getAppointments();
}, []);
return (
<div style={dashboardStyle}>
<Header />
<AppointmentList /> // <-- don't pass props
</div>
);
}
AppointmentList
function AppointmentList() { // <-- no props
const { appointments } = useContext(AppContext); // <-- access from context
return appointments.map(appt => (
<Appointment key={appt.id} appointment={appt} />
));
}

Navbar not updating after state change

As the title says my navbar is not changing the fragments after updating the state. I have no idea how to refresh it and other ideas seems to not work for me. I have tried to change the statements.
All i want to do is, after a user logs in successfully the state changes to true and the navbar updates with the corrent components. Thank you !
Home.js
import React, { useEffect } from 'react'
function Home() {
useEffect(()=>{
if(!localStorage.getItem("loggedIn")){
localStorage.setItem("loggedIn",false);
}
},[]);
return (
<div>
Home
</div>
)
}
export default Home
Login.js
import React from 'react';
import './Login.css';
import Axios from 'axios';
import { useEffect, useState } from "react";
import {useHistory} from 'react-router-dom';
function Login() {
const[username,setUsername] = useState('');
const[password,setPassword] = useState('');
const[errorMessage,setErrorMessage] = useState('');
let history = useHistory();
const login = () =>{
console.log(username);
Axios.post("http://localhost:3001/user/login",{username: username,password: password}).then((response) => {
//console.log(response);
if(response.data.loggedIn){
localStorage.setItem("loggedIn",true);
localStorage.setItem("username",response.data.username);
history.push('/');
}else{
setErrorMessage(response.data.message);
}
});
};
return (
<div className="Login">
<h1>Login to your BugTrack account !</h1>
<div className="LoginForm">
<input type="text" placeholder="USERNAME"
onChange={(event)=>{setUsername(event.target.value)}}/>
<input type="password" placeholder="PASSWORD"
onChange={(event)=>{setPassword(event.target.value)}}/>
<button onClick={login}>Login to you account</button>
<h1 style={{color: "red"}}>{errorMessage}</h1>
</div>
</div>
);
}
export default Login
Navbar.js
import React, { useEffect, useState, Component, Fragment } from 'react';
import './Navbar.css';
function Navbar() {
const [loggedIn, setLoggedIn] = useState(false);
useEffect(()=> {
setLoggedIn(localStorage.getItem("loggedIn"));
},[localStorage.getItem("loggedIn")]);
return (
<div className="Navbar">
Home
{!loggedIn ? (
<Fragment>
Profile
</Fragment>
):(
<Fragment>
Register
Login
</Fragment>
)}
</div>
);
}
export default Navbar;
You want to to use localStorage as a useEffect dependency which isn't supports for React to rerender/update the component. Check this: useEffect do not listen for localStorage - it's like duplicate of your question.

React useContext returns default values

I'm trying to create a darkmode library (named react-goodnight) based on https://github.com/luisgserrano/react-dark-mode.
This is where the context is created.
import React from 'react'
const ThemeContext = React.createContext({
theme: '',
toggle: () => {}
})
export default ThemeContext
This is my useDarkMode hook that get/sets the theme to localStorage.
import { useState, useEffect } from 'react'
const useDarkMode = () => {
const [theme, setTheme] = useState('light')
const setMode = (mode) => {
window.localStorage.setItem('theme', mode)
setTheme(mode)
}
const toggle = () => (theme === 'light' ? setMode('dark') : setMode('light'))
useEffect(() => {
const localTheme = window.localStorage.getItem('theme')
localTheme && setTheme(localTheme)
}, [])
return [theme, toggle]
}
export default useDarkMode
This is the index of my library (react-goodnight).
import React, { useContext } from 'react'
import { ThemeProvider } from 'styled-components'
import { GlobalStyles } from './globalStyles'
import { lightTheme, darkTheme } from './settings'
import ThemeContext from './themeContext'
import useDarkMode from './useDarkMode'
const Provider = ({ children }) => {
const [theme, toggle] = useDarkMode()
return (
<ThemeProvider theme={theme === 'light' ? lightTheme : darkTheme}>
<GlobalStyles />
<ThemeContext.Provider value={{ theme, toggle }}>
<button onClick={toggle}>Toggle</button>
{children}
</ThemeContext.Provider>
</ThemeProvider>
)
}
export const useDarkModeContext = () => useContext(ThemeContext)
export default Provider
And, in the end, this is my example app where I'm trying to use it.
import React from 'react'
import Provider, { useDarkModeContext } from 'react-goodnight'
const App = () => {
const { theme, toggle } = useDarkModeContext();
console.log(theme)
return (
<Provider>
<div>hey</div>
<button onClick={toggle}>Toggle</button>
</Provider>
)
}
export default App
The "Toggle" button in the library's index works fine but the one in my example app does not.
The useDarkModeContext() returns empty.
What could be the issue?
Thanks!
You are doing wrong
1st option
you can use react-goodnight provider with your index.js and use useDarkModeContext(), don't name your index.js Provider else you can not use Provider coming from react-goodnight
import Provider, { useDarkModeContext } from 'react-goodnight'
const Provider = ({ children }) => {
const [theme, toggle] = useDarkMode()
return (
<ThemeProvider theme={theme === 'light' ? lightTheme : darkTheme}>
<GlobalStyles />
<Provider>
<ThemeContext.Provider value={{ theme, toggle }}>
<button onClick={toggle}>Toggle</button>
{children}
</ThemeContext.Provider>
</Provider>
</ThemeProvider>
)
}
2nd Option
you are passing ThemeContext in your index.js so you can also access that in app.js
import React, { useContext } from 'react'
import ThemeContext from './themeContext'
const App = () => {
const theme = useContext(ThemeContext);
console.log(theme)
return (
<Provider>
<div>hey</div>
<button onClick={toggle}>Toggle</button>
</Provider>
)
}
export default App
The reason it's not working is because you are calling useContext in the very same place where you print Provider.
Why is that wrong? Because useContext looks for parent context providers. By rendering Provider in the same place you call useContext, there is no parent to look for. The useContext in your example is actually part of App component, who is not a child of Provider.
All you have to do is move the button outside of that print, to its own component, and only there do useContext (or in your case the method called useDarkModeContext.
The only change would be:
import React from 'react'
import Provider, { useDarkModeContext } from 'react-goodnight'
const App = () => {
return (
<Provider>
<div>hey</div>
<ToggleThemeButton />
</Provider>
)
}
export default App
const ToggleThemeButton = () => {
const { theme, toggle } = useDarkModeContext();
return (
<button onClick={toggle}>Switch Theme outside</button>
);
};

How to redirect to a url along with a component in react such that props passed to the component are not lost

When onClick event is triggered, I want to redirect to a new component (props passed to it) with a new url.
My App.js
import React from "react";
import Main from "./Components/Main/Main";
import "bootstrap/dist/css/bootstrap.min.css";
import styles from "./App.module.css";
import { BrowserRouter as Router, Route} from "react-router-dom";
import SearchBar from "./Components/SearchBar/SearchBar";
import AnimeInfo from "./Components/AnimeInfo/AnimeInfo";
import Cards from "./Components/Cards/Cards"
const App = () => {
return (
<Router>
<div className={styles.container}>
<SearchBar />
<Route path="/" exact component={Main} />
<Route path="/anime/info" component={AnimeInfo} />
<Route path="/anime/cards" component={Cards} />
</div>
</Router>
);
};
export default App;
In the following component, I am passing props to a component but I want to redirect to the url too, but doing so, the props passed that component are lost and I just get redirected
import React, { useEffect, useState } from "react";
import { apiDataTop, apiDataUpcoming, apiDataDay } from "../../api";
import styles from "./TopAnime.module.css";
import AnimeInfo from "../AnimeInfo/AnimeInfo";
import {
BrowserRouter as Router,
Switch,
Route,
Link,
Redirect,
} from "react-router-dom";
const TopAnime = () => {
const [animeData, setAnimeData] = useState([]);
const [animeDataHype, setAnimeDataHype] = useState([]);
const [animeDataDay, setAnimeDataDay] = useState([]);
const [image_url, setImageUrl] = useState("");
useEffect(() => {
callApi();
}, []);
const callApi = async () => {
const results = await apiDataTop();
const hypeResults = await apiDataUpcoming();
const dayResults = await apiDataDay();
setAnimeData(results);
setAnimeDataHype(hypeResults);
setAnimeDataDay(dayResults);
};
console.log(animeDataDay);
return (
<div>
<h1>Recent Release</h1>
<div className={styles.container}>
<br />
{animeDataDay === []
? null
: animeDataDay.map((anime) => {
return (
<a
href
onClick={(event) => {
event.preventDefault();
let animeName = anime.title;
animeName = animeName.replace(/\s+/g, "");
setImageUrl(anime.image_url);
console.log("image url original", anime.image_url);
console.log("image url", image_url);
}}
className={styles.move}
>
<img src={anime.image_url} alt="anime" />
<div className={styles.size}>
<h5>
<b>{anime.title}</b>
</h5>
</div>
</a>
);
})}
{image_url ? (
<Router>
// below commented approch first display the component on the same page and then redirects to the url
// but the props passed are lost !
// <Link to="/anime/info">
// <AnimeInfo image_url={image_url} />
// {window.location.href = `/anime/info`}
// </Link>
<Route
path="/anime/info"
render={() => <AnimeInfo image_url={image_url} />}
/>
</Router>
) : null}
</div>
export default TopAnime;
Following is the component, to whom I want to pass props and use the data passed to display (on a whole new page)!
import React, { useEffect, useState } from "react";
import styles from "./AnimeInfo.module.css";
console.log("The data image props issss", props.image_url);
return (
<div className={styles.container}>
<h1> I am info component</h1>
<img src={props.image_url} alt="anime" />
</div>
);
};
export default AnimeInfo;
Why not use the state property in history.push()?
See it in action here
use the history package.
then create a file at 'src/history.js'
import { createBrowserHistory } from 'history';
export default createBrowserHistory();
then in your component
import history from './history'
history.push({
pathname: '/path',
data_name: dataObject,
});
Then you can access the props in your other component:
this.props.location.data_name
Use render method in router
const renderComponent = (props, Component) => {
// write logic if needed
return <Component {...props} />
}
<Route path="/earner" render={(props) => renderComponent(props, Main)}/>

react-router go back a page how do you configure history?

Can anyone please tell me how I can go back to the previous page rather than a specific route?
When using this code:
var BackButton = React.createClass({
mixins: [Router.Navigation],
render: function() {
return (
<button
className="button icon-left"
onClick={this.navigateBack}>
Back
</button>
);
},
navigateBack: function(){
this.goBack();
}
});
Get this error, goBack() was ignored because there is no router history
Here are my routes:
// Routing Components
Route = Router.Route;
RouteHandler = Router.RouteHandler;
DefaultRoute = Router.DefaultRoute;
var routes = (
<Route name="app" path="/" handler={OurSchoolsApp}>
<DefaultRoute name="home" handler={HomePage} />
<Route name="add-school" handler={AddSchoolPage} />
<Route name="calendar" handler={CalendarPage} />
<Route name="calendar-detail" path="calendar-detail/:id" handler={CalendarDetailPage} />
<Route name="info-detail" path="info-detail/:id" handler={InfoDetailPage} />
<Route name="info" handler={InfoPage} />
<Route name="news" handler={NewsListPage} />
<Route name="news-detail" path="news-detail/:id" handler={NewsDetailPage} />
<Route name="contacts" handler={ContactPage} />
<Route name="contact-detail" handler={ContactDetailPage} />
<Route name="settings" handler={SettingsPage} />
</Route>
);
Router.run(routes, function(Handler){
var mountNode = document.getElementById('app');
React.render(<Handler /> , mountNode);
});
Update with React v16 and ReactRouter v4.2.0 (October 2017):
class BackButton extends Component {
static contextTypes = {
router: () => true, // replace with PropTypes.object if you use them
}
render() {
return (
<button
className="button icon-left"
onClick={this.context.router.history.goBack}>
Back
</button>
)
}
}
Update with React v15 and ReactRouter v3.0.0 (August 2016):
var browserHistory = ReactRouter.browserHistory;
var BackButton = React.createClass({
render: function() {
return (
<button
className="button icon-left"
onClick={browserHistory.goBack}>
Back
</button>
);
}
});
Created a fiddle with a little bit more complex example with an embedded iframe: https://jsfiddle.net/kwg1da3a/
React v14 and ReacRouter v1.0.0 (Sep 10, 2015)
You can do this:
var React = require("react");
var Router = require("react-router");
var SomePage = React.createClass({
...
contextTypes: {
router: React.PropTypes.func
},
...
handleClose: function () {
if (Router.History.length > 1) {
// this will take you back if there is history
Router.History.back();
} else {
// this will take you to the parent route if there is no history,
// but unfortunately also add it as a new route
var currentRoutes = this.context.router.getCurrentRoutes();
var routeName = currentRoutes[currentRoutes.length - 2].name;
this.context.router.transitionTo(routeName);
}
},
...
You need to be careful that you have the necessary history to go back. If you hit the page directly and then hit back it will take you back in the browser history before your app.
This solution will take care of both scenarios. It will, however, not handle an iframe that can navigate within the page (and add to the browser history), with the back button. Frankly, I think that is a bug in the react-router. Issue created here: https://github.com/rackt/react-router/issues/1874
Using React Hooks
Import:
import { useHistory } from "react-router-dom";
In stateless component:
let history = useHistory();
Call the Event:
history.goBack()
Examples do use in event Button:
<button onClick={history.goBack}>Back</button>
or
<button onClick={() => history.goBack()}>Back</button>
import withRouter
import { withRouter } from 'react-router-dom';
Export your component as:
export withRouter(nameofcomponent)
Example, on button click, call goBack:
<button onClick={this.props.history.goBack}>Back</button>
Tested on react-router-dom v4.3
I think you just need to enable BrowserHistory on your router by intializing it like that : <Router history={new BrowserHistory}>.
Before that, you should require BrowserHistory from 'react-router/lib/BrowserHistory'
Here's an example using ES6
const BrowserHistory = require('react-router/lib/BrowserHistory').default;
const App = React.createClass({
render: () => {
return (
<div><button onClick={BrowserHistory.goBack}>Go Back</button></div>
);
}
});
React.render((
<Router history={BrowserHistory}>
<Route path="/" component={App} />
</Router>
), document.body);
React Router v6
useNavigate Hook is the recommended way to go back now:
import { useNavigate } from 'react-router-dom';
function App() {
const navigate = useNavigate();
return (
<>
<button onClick={() => navigate(-1)}>go back</button>
<button onClick={() => navigate(1)}>go forward</button>
</>
);
}
Codesandbox sample
Go back/forward multiple history stack entries:
<button onClick={() => navigate(-2)}>go two back</button>
<button onClick={() => navigate(2)}>go two forward</button>
Go to specific route:
navigate("users") // go to users route, like history.push
navigate("users", { replace: true }) // go to users route, like history.replace
navigate("users", { state }) // go to users route, pass some state in
useNavigate replaces useHistory to support upcoming React Suspense/Concurrent mode better.
this.context.router.goBack()
No navigation mixin required!
ES6 method without mixins using react-router, stateless function.
import React from 'react'
import { browserHistory } from 'react-router'
export const Test = () => (
<div className="">
<button onClick={browserHistory.goBack}>Back</button>
</div>
)
Go back to specific page:
import { useHistory } from "react-router-dom";
const history = useHistory();
const routeChange = () => {
let path = '/login';
history.push(path);
};
Go back to previous page:
import { useHistory } from "react-router-dom";
const history = useHistory();
const routeChange = () => {
history.goBack()
};
Check out my working example using React 16.0 with React-router v4. check out the code Github
Use withRouter and history.goBack()
This is the idea I am implementing...
History.js
import React, { Component } from 'react';
import { withRouter } from 'react-router-dom'
import './App.css'
class History extends Component {
handleBack = () => {
this.props.history.goBack()
}
handleForward = () => {
console.log(this.props.history)
this.props.history.go(+1)
}
render() {
return <div className="container">
<div className="row d-flex justify-content-between">
<span onClick={this.handleBack} className="d-flex justify-content-start button">
<i className="fas fa-arrow-alt-circle-left fa-5x"></i>
</span>
<span onClick={this.handleForward} className="d-flex justify-content-end button">
<i className="fas fa-arrow-alt-circle-right fa-5x"></i>
</span>
</div>
</div>
}
}
export default withRouter(History)
PageOne.js
import React, { Fragment, Component } from 'react'
class PageOne extends Component {
componentDidMount(){
if(this.props.location.state && this.props.location.state.from != '/pageone')
this.props.history.push({
pathname: '/pageone',
state: {
from: this.props.location.pathname
}
});
}
render() {
return (
<Fragment>
<div className="container-fluid">
<div className="row d-flex justify-content-center">
<h2>Page One</h2>
</div>
</div>
</Fragment>
)
}
}
export default PageOne
p.s. sorry the code is to big to post it all here
This works with Browser and Hash history.
this.props.history.goBack();
This is a working BackButton component (React 0.14):
var React = require('react');
var Router = require('react-router');
var History = Router.History;
var BackButton = React.createClass({
mixins: [ History ],
render: function() {
return (
<button className="back" onClick={this.history.goBack}>{this.props.children}</button>
);
}
});
module.exports = BackButton;
You can off course do something like this if there is no history:
<button className="back" onClick={goBack}>{this.props.children}</button>
function goBack(e) {
if (/* no history */) {
e.preventDefault();
} else {
this.history.goBack();
}
}
For react-router v2.x this has changed. Here's what I'm doing for ES6:
import React from 'react';
import FontAwesome from 'react-fontawesome';
import { Router, RouterContext, Link, browserHistory } from 'react-router';
export default class Header extends React.Component {
render() {
return (
<div id="header">
<div className="header-left">
{
this.props.hasBackButton &&
<FontAwesome name="angle-left" className="back-button" onClick={this.context.router.goBack} />
}
</div>
<div>{this.props.title}</div>
</div>
)
}
}
Header.contextTypes = {
router: React.PropTypes.object
};
Header.defaultProps = {
hasBackButton: true
};
Header.propTypes = {
title: React.PropTypes.string
};
In react-router v4.x you can use history.goBack which is equivalent to history.go(-1).
App.js
import React from "react";
import { render } from "react-dom";
import { BrowserRouter as Router, Route, Link } from "react-router-dom";
import Home from "./Home";
import About from "./About";
import Contact from "./Contact";
import Back from "./Back";
const styles = {
fontFamily: "sans-serif",
textAlign: "left"
};
const App = () => (
<div style={styles}>
<Router>
<div>
<ul>
<li><Link to="/">Home</Link></li>
<li><Link to="/about">About</Link></li>
<li><Link to="/contact">Contact</Link></li>
</ul>
<hr />
<Route exact path="/" component={Home} />
<Route path="/about" component={About} />
<Route path="/contact" component={Contact} />
<Back />{/* <----- This is component that will render Back button */}
</div>
</Router>
</div>
);
render(<App />, document.getElementById("root"));
Back.js
import React from "react";
import { withRouter } from "react-router-dom";
const Back = ({ history }) => (
<button onClick={history.goBack}>Back to previous page</button>
);
export default withRouter(Back);
Demo:
https://codesandbox.io/s/ywmvp95wpj
Please remember that by using history your users can leave because history.goBack() can load a page that visitor has visited before opening your application.
To prevent such situation as described above, I've created a simple library react-router-last-location that watch your users last location.
Usage is very straight forward.
First you need to install react-router-dom and react-router-last-location from npm.
npm install react-router-dom react-router-last-location --save
Then use LastLocationProvider as below:
App.js
import React from "react";
import { render } from "react-dom";
import { BrowserRouter as Router, Route, Link } from "react-router-dom";
import { LastLocationProvider } from "react-router-last-location";
// ↑
// |
// |
//
// Import provider
//
import Home from "./Home";
import About from "./About";
import Contact from "./Contact";
import Back from "./Back";
const styles = {
fontFamily: "sans-serif",
textAlign: "left"
};
const App = () => (
<div style={styles}>
<h5>Click on About to see your last location</h5>
<Router>
<LastLocationProvider>{/* <---- Put provider inside <Router> */}
<div>
<ul>
<li><Link to="/">Home</Link></li>
<li><Link to="/about">About</Link></li>
<li><Link to="/contact">Contact</Link></li>
</ul>
<hr />
<Route exact path="/" component={Home} />
<Route path="/about" component={About} />
<Route path="/contact" component={Contact} />
<Back />
</div>
</LastLocationProvider>
</Router>
</div>
);
render(<App />, document.getElementById("root"));
Back.js
import React from "react";
import { Link } from "react-router-dom";
import { withLastLocation } from "react-router-last-location";
// ↑
// |
// |
//
// `withLastLocation` higher order component
// will pass `lastLocation` to your component
//
// |
// |
// ↓
const Back = ({ lastLocation }) => (
lastLocation && <Link to={lastLocation || '/'}>Back to previous page</Link>
);
// Remember to wrap
// your component before exporting
//
// |
// |
// ↓
export default withLastLocation(Back);
Demo: https://codesandbox.io/s/727nqm99jj
I want to update the previous answers a bit.
If you are using react-router >v6.0 then the useHistory() is not the right way to go back. You will get an error as I guess useHistory() is not present in the latest version.
So this is the updated answer
// This is a React Router v6 app
import { useNavigate } from "react-router-dom";
function App() {
const navigate = useNavigate();
return (
<>
<button onClick={() => navigate(-2)}>
Go 2 pages back
</button>
<button onClick={() => navigate(-1)}>Go back</button>
<button onClick={() => navigate(1)}>
Go forward
</button>
<button onClick={() => navigate(2)}>
Go 2 pages forward
</button>
</>
);
}
Use this useNavigate() hook.
You can read the official doc for this transition from v5 to v6 here
https://reactrouter.com/docs/en/v6/upgrading/v5
What worked for me was to import withRouter at the top of my file;
import { withRouter } from 'react-router-dom'
Then use it to wrap the exported function at the bottom of my file;
export default withRouter(WebSitePageTitleComponent)
Which then allowed me to access the Router's history prop. Full sample code below!
import React, { Component } from 'react'
import { withRouter } from 'react-router-dom'
import PropTypes from 'prop-types'
class TestComponent extends Component {
constructor(props) {
super(props)
this.handleClick = this.handleClick.bind(this)
}
handleClick() {
event.preventDefault()
this.props.history.goBack()
}
render() {
return (
<div className="page-title">
<a className="container" href="/location" onClick={this.handleClick}>
<h1 className="page-header">
{ this.props.title }
</h1>
</a>
</div>
)
}
}
const { string, object } = PropTypes
TestComponent.propTypes = {
title: string.isRequired,
history: object
}
export default withRouter(TestComponent)
On react-router-dom v6
import { useNavigate } from 'react-router-dom';
function goBack() {
const navigate = useNavigate();
return <button onClick={() => navigate(-1)}>go back</button>
}
import { withRouter } from 'react-router-dom'
this.props.history.goBack();
I am using these versions
"react": "^15.6.1",
"react-dom": "^15.6.1",
"react-router": "^4.2.0",
"react-router-dom": "^4.2.2",
Step-1
import { useHistory } from "react-router-dom";`
Step-2
let history = useHistory();
Step-3
const goToPreviousPath = (e) => {
e.preventDefault();
history.goBack()
}
step-4
<Button
onClick={goToPreviousPath}
>
Back
</Button>
REDUX
You can also use react-router-redux which has goBack() and push().
Here is a sampler pack for that:
In your app's entry point, you need ConnectedRouter, and a sometimes tricky connection to hook up is the history object. The Redux middleware listens to history changes:
import React from 'react'
import { render } from 'react-dom'
import { ApolloProvider } from 'react-apollo'
import { Provider } from 'react-redux'
import { ConnectedRouter } from 'react-router-redux'
import client from './components/apolloClient'
import store, { history } from './store'
import Routes from './Routes'
import './index.css'
render(
<ApolloProvider client={client}>
<Provider store={store}>
<ConnectedRouter history={history}>
<Routes />
</ConnectedRouter>
</Provider>
</ApolloProvider>,
document.getElementById('root'),
)
I will show you a way to hook up the history. Notice how the history is imported into the store and also exported as a singleton so it can be used in the app's entry point:
import { createStore, applyMiddleware, compose } from 'redux'
import { routerMiddleware } from 'react-router-redux'
import thunk from 'redux-thunk'
import createHistory from 'history/createBrowserHistory'
import rootReducer from './reducers'
export const history = createHistory()
const initialState = {}
const enhancers = []
const middleware = [thunk, routerMiddleware(history)]
if (process.env.NODE_ENV === 'development') {
const { devToolsExtension } = window
if (typeof devToolsExtension === 'function') {
enhancers.push(devToolsExtension())
}
}
const composedEnhancers = compose(applyMiddleware(...middleware), ...enhancers)
const store = createStore(rootReducer, initialState, composedEnhancers)
export default store
The above example block shows how to load the react-router-redux middleware helpers which complete the setup process.
I think this next part is completely extra, but I will include it just in case someone in the future finds benefit:
import { combineReducers } from 'redux'
import { routerReducer as routing } from 'react-router-redux'
export default combineReducers({
routing, form,
})
I use routerReducer all the time because it allows me to force reload Components that normally do not due to shouldComponentUpdate. The obvious example is when you have a Nav Bar that is supposed to update when a user presses a NavLink button. If you go down that road, you will learn that Redux's connect method uses shouldComponentUpdate. With routerReducer, you can use mapStateToProps to map routing changes into the Nav Bar, and this will trigger it to update when the history object changes.
Like this:
const mapStateToProps = ({ routing }) => ({ routing })
export default connect(mapStateToProps)(Nav)
Forgive me while I add some extra keywords for people: if your component isn't updating properly, investigate shouldComponentUpdate by removing the connect function and see if it fixes the problem. If so, pull in the routerReducer and the component will update properly when the URL changes.
In closing, after doing all that, you can call goBack() or push() anytime you want!
Try it now in some random component:
Import in connect()
You don't even need mapStateToProps or mapDispatchToProps
Import in goBack and push from react-router-redux
Call this.props.dispatch(goBack())
Call this.props.dispatch(push('/sandwich'))
Experience positive emotion
If you need more sampling, check out: https://www.npmjs.com/package/react-router-redux
Simply use like this
<span onClick={() => this.props.history.goBack()}>Back</span>
The only solution that worked for me was the most simple. No additional imports needed.
<a href="#" onClick={() => this.props.history.goBack()}>Back</a>
Tks, IamMHussain
React Router uses the HTML5 History API, which builds on the browser history API to provide an interface to which we can use easily in React apps. History API . So without import anything (useHistory, etc)
for functional component:
<button onClick={()=>{ window.history.back() }}> Back </button>
for class component:
<button onClick={()=>{ this.window.history.back() }}> Back </button>
In react-router v6, when you want to go back to the previous page, you can do that with useNavigate:
Step 1:
import { useNavigate } from "react-router-dom";
Step2:
const navigate = useNavigate();
Step 3: if you want to go back to the previous page, use navigate(-1):
<button onClick={() => navigate(-1)}> Back </button>
If you are using react-router v6, when you want to go back to the previous page you can do that with the Link:
Step 1: you need to import Link from react-router-dom
import { Link } from 'react-router-dom';
Step 2: wrap up the button with Link like this. It works perfectly.
<Link to='..'>
<Button type='button'>Go Back</Button>
</Link>
Call the following component like so:
<BackButton history={this.props.history} />
And here is the component:
import React, { Component } from 'react'
import PropTypes from 'prop-types'
class BackButton extends Component {
constructor() {
super(...arguments)
this.goBack = this.goBack.bind(this)
}
render() {
return (
<button
onClick={this.goBack}>
Back
</button>
)
}
goBack() {
this.props.history.goBack()
}
}
BackButton.propTypes = {
history: PropTypes.object,
}
export default BackButton
I'm using:
"react": "15.6.1"
"react-router": "4.2.0"
if you are using react-native drawer navigation as main router in your application and want to control back button behavior and go back historically you can use to control back button.
<NavigationContainer>
<Drawer.Navigator
backBehavior="history">
// your screens come here
</Drawer.Navigator>
</NavigationContainer>
This piece of code will do the trick for you.
this.context.router.history.goBack()
According to https://reacttraining.com/react-router/web/api/history
For "react-router-dom": "^5.1.2",,
const { history } = this.props;
<Button onClick={history.goBack}>
Back
</Button>
YourComponent.propTypes = {
history: PropTypes.shape({
goBack: PropTypes.func.isRequired,
}).isRequired,
};

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