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>
);
};
Related
I am trying to access LaunchDarkly flags from my App context. The code looks like:
import { useState, useEffect } from 'react';
import { Helmet } from 'react-helmet';
import { MuiPickersUtilsProvider } from '#material-ui/pickers';
import DateFnsUtils from '#date-io/date-fns';
import { ApolloProvider } from 'react-apollo';
import { Route, Router, Switch } from 'react-router-dom';
import { withLDProvider } from 'launchdarkly-react-client-sdk';
import { Loading } from '#ap/owl-ui-controls';
import { useAuth0 } from './context/Authentication';
import LabelContext from './context/LabelContext';
import { CommunityByNameContext } from './context/CommunityByNameContext';
import { segment_init } from './utils/segment';
import withConfig, { ConfigEnum } from './utils/withConfig';
import client from './utils/graphQLClient';
import labels from './config/labels';
import CurrentUser from './services/CurrentUser';
import Layout from './Layout';
import history from './utils/history';
import { SearchCommunity } from './common/Filters/SearchNameFilter/findCommunitiesQuery';
import AmplitudeContext, { AmplitudeData } from './context/AmplitudeContext';
import { DisclosuresContextProvider } from './context/DisclosuresContext';
import placeService from './services/placesService';
import { FeaturedCommunitiesIdsProvider } from './context/FeaturedCommunitiesIdsContext';
import { optimizelyInit } from './utils/optimizely';
import { FamilyFileContextProvider } from './context/FamilyFileContext';
const segmentKey = withConfig(ConfigEnum.SEGMENT_KEY);
const currentUserString = localStorage.getItem('CURRENT_USER');
const App = () => {
const { loading } = useAuth0();
const [currentUser, setCurrentUser] = useState(currentUserString ? JSON.parse(currentUserString) : null);
const [communityByName, setCommunityByName] = useState<SearchCommunity | null>(null);
const [amplitude, setAmplitude] = useState<AmplitudeData>({});
useEffect(() => {
placeService.init();
}, []);
if (loading) {
return <Loading />;
}
return (
<>
<Helmet>
<title>Beacon</title>
<script type="text/javascript">{optimizelyInit(flags)}</script>
<script type="text/javascript">{segment_init(segmentKey, currentUser)}</script>
</Helmet>
<LabelContext.Provider value={labels}>
<CommunityByNameContext.Provider value={{ communityByName, setCommunityByName }}>
<FeaturedCommunitiesIdsProvider>
<AmplitudeContext.Provider value={{ amplitude, setAmplitude }}>
<MuiPickersUtilsProvider utils={DateFnsUtils}>
<ApolloProvider client={client}>
{/* #ts-ignore */}
<CurrentUser onUserChanged={(currentUser: any) => setCurrentUser(currentUser)}>
<FamilyFileContextProvider>
<DisclosuresContextProvider>
<Router history={history}>
<Switch>
<Route path="/communities" component={Layout} />
</Switch>
</Router>
</DisclosuresContextProvider>
</FamilyFileContextProvider>
</CurrentUser>
</ApolloProvider>
</MuiPickersUtilsProvider>
</AmplitudeContext.Provider>
</FeaturedCommunitiesIdsProvider>
</CommunityByNameContext.Provider>
</LabelContext.Provider>
</>
);
};
export default withLDProvider({
clientSideID: withConfig(ConfigEnum.LD_CLIENT_SIDE_ID),
})(App);
My nested components, like for example <CurrentUser /> get LD flags, and I am able to access them as:
const CurrentUser = ({ children, flags, onUserChanged })
However, I also need LD flags inside <App /> so I could do:
<Helmet>
<title>Beacon</title>
{flags.optimizely && <script type="text/javascript">{optimizelyInit(flags)}</script>}
<script type="text/javascript">{segment_init(segmentKey, currentUser)}</script>
</Helmet>
I have tried accessing flags with const App = ({ flags }), but the value is always undefined.
I even tried sticking the below into a component
const DocumentHead = ({ flags, segmentKey, currentUser }) => (
<Helmet>
<title>Beacon</title>
<script type="text/javascript">{optimizelyInit(flags)}</script>
<script type="text/javascript">{segment_init(segmentKey, currentUser)}</script>
</Helmet>
);
Flags are still undefined.
Suggestions?
Apparently, there is a useFlags hook. We can get flags as:
const flags = useFlags();
This can be called from the <App /> component.
I am creating my react app with material-ui Snackbar.
In my project I have a lot of components and don't want to insert <Snackbar/> in each of them.
Is there a way to create function that will show snackbar, then just import and use this function in each component?
Something like:
import showSnackbar from 'SnackbarUtils';
showSnackbar('Success message');
You have to do it in react way. You can achieve this by creating a Higher Order Component.
Create a HOC that returns a snackbar component along with the wrappedComponent
Create a function in that HOC which accepts message, severity (if you are using Alert like me), duration and sets the appropriate states which are set to the props of the snackbar. And pass that function as a prop to the wrappedComponent.
Finally import this HOC wherever you want to display a snackbar, pass your component in it and call the HOC function from the prop (this.prop.functionName('Hello there!')) in the event handler where you want to display a snackbar and pass in a message.
Check this out.
https://stackblitz.com/edit/snackbar-hoc?file=src/SnackbarHOC.js
extend it as a Hook, and then you can call it once and use state with effects to show:
import { useSnackbar } from 'notistack';
import IconButton from "#mui/material/IconButton";
import CloseIcon from "#mui/material/SvgIcon/SvgIcon";
import React, {Fragment, useEffect, useState} from "react";
const useNotification = () => {
const [conf, setConf] = useState({});
const { enqueueSnackbar, closeSnackbar } = useSnackbar();
const action = key => (
<Fragment>
<IconButton onClick={() => { closeSnackbar(key) }}>
<CloseIcon />
</IconButton>
</Fragment>
);
useEffect(()=>{
if(conf?.msg){
let variant = 'info';
if(conf.variant){
variant = conf.variant;
}
enqueueSnackbar(conf.msg, {
variant: variant,
autoHideDuration: 5000,
action
});
}
},[conf]);
return [conf, setConf];
};
export default useNotification;
Then you can use it:
const [msg, sendNotification] = useNotification();
sendNotification({msg: 'yourmessage', variant: 'error/info.....'})
Here is a sample code for fully working example using Redux, Material-ui and MUI Snackbar
import { random } from 'lodash'
import { Action } from 'redux'
import actionCreatorFactory, { isType } from 'typescript-fsa'
const actionCreator = actionCreatorFactory()
export type Notification = {
message: string
}
export type NotificationStore = Notification & {
messageId: number
}
export const sendNewNotification =
actionCreator<Notification>('NEW_NOTIFICATION')
const defaultState: NotificationStore = { message: '', messageId: 1 }
const reducer = (
state: NotificationStore = defaultState,
action: Action
): NotificationStore => {
if (isType(action, sendNewNotification)) {
const {
payload: { message }
} = action
return { message, messageId: random(0, 200000) }
}
return state
}
export default reducer
// useNotification to get state from Redux, you can include them into same file if you prefer
import { NotificationStore } from './notification'
export function useNotification(): NotificationStore {
return useSelector<NotificationStore>(
(state) => state.notification
)
}
// Notification React-component - Notification.tsx
import React, { useState } from 'react'
import Button from '#mui/material/Button'
import Snackbar from '#mui/material/Snackbar'
import IconButton from '#mui/material/IconButton'
import CloseIcon from '#mui/icons-material/Close'
type Props = {
message: string
}
export function Notification({ message }: Props): JSX.Element | null {
const [notiOpen, setNotiOpen] = useState(true)
if (!message) {
return null
}
return (
<Snackbar
anchorOrigin={{
vertical: 'bottom',
horizontal: 'left'
}}
open={notiOpen}
autoHideDuration={10000}
onClose={() => setNotiOpen(false)}
message={message}
action={
<React.Fragment>
<Button
color="secondary"
size="small"
onClick={() => setNotiOpen(false)}
>
Close
</Button>
<IconButton
size="small"
aria-label="close"
color="inherit"
onClick={() => setNotiOpen(false)}
>
<CloseIcon fontSize="small" />
</IconButton>
</React.Fragment>
}
/>
)
}
// Main App.tsx to run my application
import { Notification } from "./Notification.tsx"
import { useDispatch } from 'react-redux'
import { BrowserRouter as Router, Route, Switch } from 'react-router-dom'
const App: React.FC<AppProps> = () => {
const dispatch = useDispatch()
const { message, messageId } = useNotification()
return (
<ThemeProvider theme={appTheme}>
<Router>
<Switch>
<Route path="/public/:projectId" component={ProjectPage} />
<Route path="/login" component={LoginPage} />
<Route render={() => <PageNotFound />} />
</Switch>
</Router>
<Notification key={messageId} message={message} />
</ThemeProvider>
)
}
export default App
// Usage of hook in application - FileSomething.tsx
import { useDispatch } from 'react-redux'
import { useEffect } from 'react'
import { sendNewNotification } from 'src/redux/notification'
export function FileSomething(): JSX.Element {
function sendNotification() {
dispatch(
sendNewNotification({
message: 'Hey, im a notification'
})
)
}
useEffect(() => {
sendNotification()
}, [])
return (
<div>Component doing something</div>
)
}
I recently built a components library but when I import my components my IDE doesn't show autocomplete props like other components do (based on propTypes) :
In my library, all components are exported with a HOC and I found out that by removing the HOC the props are now available in auto complete. Here's my HOC :
import * as React from 'react'
import hoistNonReactStatics from 'hoist-non-react-statics'
import PropTypes from 'prop-types'
import { defaultTheme } from '../styles/defaultTheme'
const withTheme = (WrappedComponent) => {
const ThemeContext = React.createContext(defaultTheme)
const Enhance = (props) => {
const { _reactThemeProviderForwardedRef, ...rest } = props
return (
<ThemeContext.Consumer>
{(theme) => (
<WrappedComponent
{...rest}
theme={theme}
ref={_reactThemeProviderForwardedRef}
/>
)}
</ThemeContext.Consumer>
)
}
Enhance.propTypes = {
_reactThemeProviderForwardedRef: PropTypes.any,
...WrappedComponent.propTypes,
}
const ResultComponent = React.forwardRef((props, ref) => (
<Enhance {...props} _reactThemeProviderForwardedRef={ref} />
))
ResultComponent.displayName = `withTheme(${
WrappedComponent.displayName || WrappedComponent.name
})`
return hoistNonReactStatics(ResultComponent, WrappedComponent)
}
export default withTheme
I'm probably doing something wrong in my withTheme but I cannot find out what.
Here is one of the components :
import React from 'react'
import { Text, StyleSheet, TextPropTypes } from 'react-native'
import PropTypes from 'prop-types'
import { buildStyleSheet } from '../util/style-helpers'
import { withTheme } from '../core/theming'
const CustomText = React.forwardRef((props, ref) => {
const { children, className = '', style, theme, ...others } = props
const customStyle = buildStyleSheet(className, 'text', theme)
return (
<Text
ref={ref}
style={StyleSheet.flatten([customStyle, style])}
{...others}
>
{children}
</Text>
)
})
const propTypes = {
children: PropTypes.any,
className: PropTypes.string,
theme: PropTypes.object.isRequired,
...TextPropTypes,
}
CustomText.displayName = 'CustomText'
CustomText.propTypes = propTypes
export default withTheme(CustomText)
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 ||Â initialState);
I'm building a quick authentication higher order component in Next.js and am getting some problems with the following code:
import SignIn from "../components/sign-in";
import { connect } from "react-redux";
import { useRouter } from "next/router";
const AuthenticationCheck = WrappedComponent => {
const { isAuthenticated, ...rest } = props;
const router = useRouter();
const protectedPages = ["/colours", "/components"];
const pageProtected = protectedPages.includes(router.pathname);
return !isAuthenticated && pageProtected ? (
<SignIn />
) : (
<WrappedComponent {...rest} />
);
};
function mapStateToProps(state) {
return {
isAuthenticated: state.auth.isAuthenticated
};
}
export default connect(mapStateToProps)(AuthenticationCheck);
If I change the code to remove redux & connect, it looks like this, and works perfectly.
const AuthenticationCheck = WrappedComponent => {
const { ...rest } = props;
const router = useRouter();
const protectedPages = ["/colours", "/components"];
const pageProtected = protectedPages.includes(router.pathname);
return pageProtected ? <SignIn /> : <WrappedComponent {...rest} />;
};
export default AuthenticationCheck;
I've been reading every SO, redux documentation etc for the last couple of hours, and I can't really find anything that matches what I'm doing, although I can't believe it's an uncommon use case.
Am I missing something obvious?
Solution: (Thankyou Dima for your help!)
So the final code that ended up working is:
import SignIn from "../components/sign-in";
import { connect } from "react-redux";
import { useRouter } from "next/router";
import { compose } from "redux";
const AuthenticationCheck = WrappedComponent => {
const authenticationCheck = props => {
const { isAuthenticated, ...rest } = props;
const router = useRouter();
const protectedPages = ["/colours", "/components"];
const pageProtected = protectedPages.includes(router.pathname);
return !isAuthenticated && pageProtected ? (
<SignIn />
) : (
<WrappedComponent {...rest} />
);
};
return authenticationCheck;
};
function mapStateToProps(state) {
return {
isAuthenticated: state.auth.isAuthenticated
};
}
export default compose(connect(mapStateToProps), AuthenticationCheck);
This works perfectly! 🙂
connect expects to get React component as a last argument, but you are sending HOC instead. You need to put connect and wrapper inside compose function. See below
import React from 'react'
import {compose} from 'redux'
import {connect} from 'react-redux'
import {doSomething} from './actions'
const wrapComponent = Component => {
const WrappedComponent = props => {
return (
<Component {...props} />
)
}
return WrappedComponent
}
const mapStateToProps = state => {
return {
prop: state.prop,
}
}
export default compose(
connect(mapStateToProps, {doSomething}),
wrapComponent
)
And the useit like this.
import React from 'react'
import withWrapper from 'your/path'
const Component = props => 'Component'
export default withWrapper(Component)