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ReactJs: How to get api data in child component with props?

I am trying to call api data only once thats way I call api in home.js file with componentdidmount in class component and i want to render this data in many child components with functional components.when i call api in every each child component,its work but when i try to call with props coming only empty array by console.log please help.
import React from 'react'
import '../styles/home.css'
import axios from 'axios';
import Teaser from './Teaser'
import Second from './Second'
import Opening from './Opening'
import Menu from './Menu'
export default class Home extends React.Component {
state = {
posts: []
}
componentDidMount() {
axios.get("https://graph.instagram.com/me/media?fields=id,caption,media_url,permalink,username&access_token=IGQ")
.then(res => {
const posts = res.data.data;
this.setState({ posts });
})
}
render() {
return (
<>
<Teaser/>
<Second/>
<Opening/>
<Menu posts={this.state.posts}/>
</>
)
}
}
import React from 'react'
import axios from 'axios';
function Menu(props) {
const {posts} = props.posts;
console.log(props);
return (
<>
{posts.map(
(post) =>
post.caption.includes('#apegustosa_menu') &&
post.children.data.map((x) => (
<div className="menu_item" key={x.id}>
<img className="menu_img" src={x.media_url} alt="image" />
</div>
)),
)}
</>
)
}
export default Menu

How to use react-router-dom v6 navigate in class component

I installed react-router-dom v6 and I want to use a class based component, in previous version of react-router-dom v5 this.props.history() worked for redirect page after doing something but this code not working for v6 .
In react-router-dom v6 there is a hook useNavigate for functional component but I need to use it in class base component , Please help me how to use navigate in class component ?

In the react-router-dom v6, the support for history has been deprecated but instead of it, navigate has been introduced. If you want to redirect user to a specific page on success of a specific event, then follow the steps given below:
Create a file named as withRouter.js, and paste the code given below in this file:
import { useNavigate } from 'react-router-dom';
export const withRouter = (Component) => {
const Wrapper = (props) => {
const navigate = useNavigate();
return (
<Component
navigate={navigate}
{...props}
/>
);
};
return Wrapper;
};
Now, in whichever class based component you want to redirect the user to a specific path/component, import the above withRouter.js file there and use this.props.navigate('/your_path_here') function for the redirection.
For your help, a sample code showing the same has been given below:
import React from 'react';
import {withRouter} from '.your_Path_To_Withrouter_Here/withRouter';
class Your_Component_Name_Here extends React.Component{
constructor(){
super()
this.yourFunctionHere=this.yourFunctionHere.bind(this);
}
yourFunctionHere()
{
this.props.navigate('/your_path_here')
}
render()
{
return(
<div>
Your Component Code Here
</div>
)
}
}
export default withRouter(Your_Component_Name_Here);
Above Code works Perfect. And this is just a small extension.
If you want onclick function here is the code:
<div className = "row">
<button className= "btn btn-primary"
onClick={this.yourFunctionHere}>RedirectTo</button>
</div>

in class base component for redirect user follow this step :
first import some component like this
import { Navigate } from "react-router-dom"
now make a state for Return a boolean value like this:
state = {
redirect:false
}
now insert Naviagate component to bottom of your component tree
but use && for conditional rendring like this :
{
this.state.redirect && <Navigate to='/some_route' replace={true}/>
}
now when you want redirect user to some page just make true redirect state
on a line of code you want
now you can see you navigate to some page :)

Try this:
import {
useLocation,
useNavigate,
useParams
} from "react-router-dom";
export const withRouter = (Component) => {
function ComponentWithRouterProp(props) {
let location = useLocation();
let navigate = useNavigate();
let params = useParams();
return (
<Component
{...props}
router={{ location, navigate, params }}
/>
);
}
return ComponentWithRouterProp;
}
and just used this function, in my case:
import { withRouter } from '../utils/with-router';
import './menu-item.styles.scss';
const MenuItem = ({title, imageUrl, size, linkUrl,router}) =>(
<div
className={`${size} menu-item`} onClick={() => router.navigate(`${router.location.pathname}${linkUrl}`)}
>
<div className='background-image'
style={{
backgroundImage: `url(${imageUrl})`
}} />
<div className="content">
<h1 className="title">{title.toUpperCase()}</h1>
<span className="subtitle">SHOP NOW</span>
</div>
</div>
)
export default withRouter(MenuItem);
I found this solution here https://www.reactfix.com/2022/02/fixed-how-can-i-use-withrouter-in-react.html
Other solution is useNavigate, for example:
<button onClick={() => {navigate("/dashboard");}} >
Dashboard
</button>

In a react class component use <Navigate>. From the react router docs:
A <Navigate> element changes the current location when it is rendered. It's a component wrapper around useNavigate, and accepts all the same arguments as props.

Try creating a reusable functional Component like a simple button and you can use it in your class component.
import React from "react";
import { useNavigate } from "react-router-dom";
const NavigateButton = ( { buttonTitle, route,isReplaced}) => {
const navigate = useNavigate();
return (
<button
className = "btn btn-primary"
onClick = { () => {
navigate( route , {replace:isReplaced} )
}}
>
{buttonTitle}
</button>;
);
});
export default NavigateButton;
After this, you can use NavigateButton in any of your class Components. And it will work.
<NavigateButton title = {"Route To"} route = {"/your_route/"} isReplaced = {false}/>

Found this explanation from the GitHub react-router issue thread, this explained how to use react-router 6 with class components
https://github.com/remix-run/react-router/issues/8146
I got this code from the above issue explanation
import React,{ Component} from "react";
import { useNavigate } from "react-router-dom";
export const withNavigation = (Component : Component) => {
return props => <Component {...props} navigate={useNavigate()} />;
}
//classComponent
class LoginPage extends React.Component{
submitHandler =(e) =>{
//successful login
this.props.navigate('/dashboard');
}
}
export default withNavigation(LoginPage);

If you need to use params for data fetching, writing a logic in your ClassComponent and render component depending on them, then create wrapper for your ClassComponentContainer
import { useLocation, useParams } from 'react-router-dom';
import ClassComponentContainer from './ClassComponentContainer';
export default function ClassComponentWrap(props) {
const location = useLocation();
const params = useParams();
return <ClassComponentContainer location={location} params={params} />
}
after it just use params in ClassComponent which is in props
import React from 'react';
import { connect } from 'react-redux';
import axios from 'axios';
import PresentationComponent from './PresentationComponent';
class ClassComponent extends React.Component {
componentDidMount() {
let postID = this.props.params.postID;
axios.get(`https://jsonplaceholder.typicode.com/posts/${postID}`)
.then((response) => {console.log(response)})
}
render() {
return <PresentationComponent {...this.props} />
}
}
const mapStateToProps = (state) => {...}
const mapDispatchToProps = (dispatch) => {...}
const ClassComponentContainer = connect(mapStateToProps, mapDispatchToProps)(ClassComponent);
export default ClassComponentContainer;
and use ClassComponentWrap component in Route element attribute
import { BrowserRouter, Route, Routes } from "react-router-dom";
import ClassComponentWrap from './components/ClassComponentWrap';
export default function App(props) {
return (
<BrowserRouter>
<Routes>
<Route path="/posts/:postID?" element={<ClassComponentWrap />} />
</Routes>
</BrowserRouter>
);
}

Here is my solution:
import React, { Component } from "react";
import { useNavigate } from "react-router-dom";
class OrdersView extends Component {
Test(props){
const navigate = useNavigate();
return(<div onClick={()=>{navigate('/')}}>test{props.test}</div>);
}
render() {
return (<div className="">
<this.Test test={'click me'}></this.Test>
</div>);
}
}

Mobx store in react doesn't rerender components

I'm trying to understand mobx. After annotations caused a lot of trouble, I decided to use a global store as described here. My store looks like this:
import {
makeObservable,
observable,
action
} from "mobx";
class Store {
constructor() {
makeObservable(this, {
fetchWorkouts: action,
user: observable,
allWorkouts: observable,
selectedWorkout: observable,
currentStep: observable,
setUser: action
})
}
user = {
uid: null,
email: null,
name: null
}
allWorkouts = []
selectedWorkout = {}
currentStep = 0
fetchWorkouts() {
}
setUser(newUser) {
this.user = newUser;
}
}
const store = new Store()
export default store;
My new user comes directly from the login, which looks like this:
import {Button} from "semantic-ui-react";
import {useHistory} from "react-router-dom"
import React from 'react';
import store from "../../context/Store";
import {toJS} from "mobx";
export default function SubmitLogin(props) {
let history = useHistory();
// eslint-disable-next-line react-hooks/exhaustive-deps
const loginUser = async () => {
let bodyObj = {
email: props.email,
pw: props.password
}
let queryString = "http://localhost:3001/user/login/" + bodyObj.email + "/" + bodyObj.pw;
await fetch(queryString).then(response => response.json()).then(json => store.setUser(json)).then(() => console.log(toJS(store.user))).then(() => history.push("/"));
}
return (
<>
<Button className={"loginRegisterButton"} onClick={loginUser}>Submit</Button>
</>
)
}
To test everything, I am trying to display the uid in my header like this:
import React, {Component} from 'react';
import {Link} from "react-router-dom";
import store from "../context/Store";
class Toolbar extends Component {
render() {
return (
<div id={"toolbarDiv"}>
<p style={{color: "white"}}>{store.user.uid}</p>
</div>
);
}
}
export default Toolbar
However, even after I receive the uid from my server and can print it in my login component, I assume that the data gets correctly assigned to the user variable in the store. Unfortunately, after pressing the sign in button and getting redirected to "/", there is nothing in the toolbar. How can I access the variables correctly?

I think you still need to wrap Toolbar and SubmitLogin in an observer call:
import React, {Component} from 'react';
import {Link} from "react-router-dom";
import { observer } from "react-mobx";
import store from "../context/Store";
class Toolbar extends Component {
render() {
return (
<div id={"toolbarDiv"}>
<p style={{color: "white"}}>{store.user.uid}</p>
</div>
);
}
}
export default observer(Toolbar);
Ref: https://mobx.js.org/react-integration.html

How to detect if another component is present in the document?

I have a site built with React Static that has a Header component that is always present. Depending on if the current page has a hero component or not, the Header should be either light or dark.
The Header is rendered outside of the routes and the useEffect is triggered before the children is rendered. This is probably because of the routing.
This is the current code:
// App.js
import React, { useState, useEffect } from 'react'
import { Root, Routes } from 'react-static'
export default () => {
const [useDarkTheme, setUseDarkTheme] = useState(false);
useEffect(() => {
if (typeof document !== "undefined") {
const heroPresent = document.querySelectorAll(".o-hero").length > 0;
console.log("The hero is present: " + heroPresent);
setUseDarkTheme(!heroPresent);
}
})
return (
<Root>
<React.Suspense fallback={ <em>Loading...</em> }>
<Header useDarkTheme={ useDarkTheme } />
<Routes default />
</React.Suspense>
</Root>
);
}
What will be rendered at <Routes default /> is the static pages configured in React Static's static.config.js.
Below is an example of the Hero component:
// Hero.js
import React from "react";
export default () => {
console.log("This is the Hero rendering. If this exist, the Header should be dark.");
return (
<div className="o-hero">
<p>Hero!</p>
</div>
);
}
When I run the application and look at the logs this is what I get:
The hero is present: false
This is the Hero rendering. If this exist, the Header should be dark.
How could I somehow detect the presence of the Hero from the Header although the Hero is in a router and the Header is not? This feels like quite a common use case, but I could not find any info on the interwebs.
Thanks in advance!

So I ended up using useContext to provide all children with a getter and a setter for the Header's theme (dark or light). The solution is very much inspired from this answer. The solution looks like this:
// App.js
import React, { useState, useContext } from 'react'
import { Root, Routes } from 'react-static'
import { HeaderThemeContext } from "./context";
export default () => {
const { theme } = useContext(HeaderThemeContext);
const [headerTheme, setHeaderTheme] = useState(theme);
return (
<Root>
<React.Suspense fallback={ <em>Loading...</em> }>
<HeaderThemeContext.Provider value={ { theme: headerTheme, setTheme: setHeaderTheme } }>
<Header theme={ headerTheme } />
<Routes default />
</HeaderThemeContext.Provider>
</React.Suspense>
</Root>
);
}
// Hero.js
import React from "react";
import { headerThemes, setHeaderTheme } from "./context";
export default () => {
setHeaderTheme(headerThemes.DARK);
console.log("This is the Hero rendering. If this exist, the Header should be dark.");
return (
<div className="o-hero">
<p>Hero!</p>
</div>
);
}
// context.js
import React, { createContext, useContext } from "react";
export const headerThemes = {
LIGHT: "light",
DARK: "dark",
};
export const HeaderThemeContext = createContext({
theme: headerThemes.LIGHT,
setTheme: () => {}
});
// This is a hook and can only be used in a functional component with access to the HeaderThemeContext.
export const setHeaderTheme = theme => useContext(HeaderThemeContext).setTheme(theme);
This gives global access to set and get the header theme, which might not be optional, but it works for now and I think it's fine. Please let me know if there is a better way of doing this.

React 16.3 Context API -- Provider/Consumer issues

I have been doing some experiment on React 16.3.1 ContextAPI. and I encountered into something that I couldn't fathom. I was hoping I could use your help.
Note: The problem have been solved but, its not the solution I am looking for.
Let start with first experiment on multiple components within same file Index.js.
import React, { Component, createContext } from 'react';
const { Provider, Consumer } = createContext();
class AppProvider extends Component {
state = {
name: 'Superman',
age: 100
};
render() {
const increaseAge = () => {
this.setState({ age: this.state.age + 1 });
};
const decreaseAge = () => {
this.setState({ age: this.state.age - 1 });
};
return (
<Provider
value={{
state: this.state,
increaseAge,
decreaseAge
}}
>
{this.props.children}
</Provider>
);
}
}
class Person extends Component {
render() {
return (
<div className="person">
<Consumer>
{context => (
<div>
<p>I'm {context.state.name}</p>
<p>I'm {context.state.age}</p>
<button onClick={context.increaseAge}>
<span>+</span>
</button>
<button onClick={context.decreaseAge}>
<span>-</span>
</button>
</div>
)}
</Consumer>
</div>
);
}
}
class App extends Component {
render() {
return (
<AppProvider>
<div className="App">
<p>Imma Apps</p>
<Person />
</div>
</AppProvider>
);
}
}
export default App;
As result, this render out perfect without any error. I am able to see name (Superman) and age (100). I am able to increase and decrease age by 1.
As you can see, I have imported {createContext} from react then created {Provider, Consumer}. Wrapped <Provider> with state value and <Consumer>.
Next Experiment, was exact copy each component from index.js and paste them separately into their own files.
AppProvider.js
import React, { Component, createContext } from 'react';
const { Provider, Consumer } = createContext();
class AppProvider extends Component {
state = {
name: 'Superman',
age: 100
};
render() {
const increaseAge = () => {
this.setState({ age: this.state.age + 1 });
};
const decreaseAge = () => {
this.setState({ age: this.state.age - 1 });
};
return (
<Provider
value={{
state: this.state,
increaseAge,
decreaseAge
}}
>
{this.props.children}
</Provider>
);
}
}
export default AppProvider;
Person.js
import React, { Component, createContext } from 'react';
const { Provider, Consumer } = createContext();
class Person extends Component {
render() {
return (
<div className="person">
<Consumer>
{context => (
<div>
<p>I'm {context.state.name}</p>
<p>I'm {context.state.age}</p>
<button onClick={context.increaseAge}>
<span>+</span>
</button>
<button onClick={context.decreaseAge}>
<span>-</span>
</button>
</div>
)}
</Consumer>
</div>
);
}
}
export default Person;
App.js
import React, { Component, createContext } from 'react';
const { Provider, Consumer } = createContext();
class App extends Component {
render() {
return (
<AppProvider>
<div className="App">
<p>Imma Apps</p>
<Person />
</div>
</AppProvider>
);
}
}
export default App;
As result, I am getting error - TypeError: Cannot read property 'state' of undefined.
I am unable to grasp what the exactly error was.. All I did was copy and paste each into files without changing any syntax.
Although, Alternative method was to create a new file and add syntax following...
Context.js
import { createContext } from 'react';
const Context = createContext();
export default Context;
Then go into each files (AppProvider.js. Person.js and App.js) and replace...
import React, { Component, createContext } from 'react';
const { Provider, Consumer } = createContext();'
...into...
import Context from './Context.js';. Also replace... <Provider> into <Context.Provider> and <Consumer> into <Context.Consumer>.
And this killed the error. However, this is not the solution I am looking for. I wanted to use <Provider> tag instead of <Context.Provider>.
Question is, Why am I getting this error?
Why am I unable to use this method...
import React, { Component, createContext } from 'react';
const { Provider, Consumer } = createContext();'
for each components in separate files so I could use <Provider> tag ?
Are there any way around to get the solution I'm looking for?
Your help is appreciated and Thanks in advance.

Your are getting TypeError: Cannot read property 'state' of undefined.
Beacuse every time you call const { Provider, Consumer } = createContext(); it creates a new object, this object need to be exported in order for consumers to consume this specific object.
So in person.js
when you try doing {context.state.age} it really does not have state on this object, you just created a new Context which is empty or rather with React internal methods and properties.
So in order to consume the same object just export it, like you did in Context.js and instead of doing:
import { createContext } from 'react';
const Context = createContext();
export default Context;
replace to:
import { createContext } from 'react';
const { Provider, Consumer } = createContext();
export { Consumer, Provider };
Then when you want to use it in other files ( meaning import it ) just call:
import { Consumer, Provider } from './Context.js';