Props not getting Rendered in NextJs - reactjs

I have a post page in blog model, which includes Detail and Comment Component. getStaticProps from the post page gets the data, and I am passing this data as props to the Detail Component. Yet the the Detail component is not getting rendered.
Here's the post page:
import BlogDetail from "../../components/BlogDetail/BlogDetail"
import { CSSTransition } from 'react-transition-group'
import AuthContextProvider from "../../context/AuthContext"
import Cookie from "../../components/Cookie"
import { ThemeContext } from "../../context/ThemeContext"
import { useContext } from "react"
import '#fortawesome/fontawesome-svg-core/styles.css'
import dynamic from 'next/dynamic'
const Navbar = dynamic(() => import("../../components/Navbar"), { ssr: false })
import axios from "axios"
import { baseURL } from "../../functions/baseUrl"
export const getStaticPaths = async () => {
const res = await axios.get(baseURL + "/post/");
const info = await res.data
const paths = info.map(datum => {
return {
params: { slug: datum.slug }
}
})
return {
paths,
fallback: false
}
}
export const getStaticProps = async (context) => {
const slug = context.params.slug;
const res = await axios.get(baseURL + '/post/' + slug + "/");
const data = await res.data;
return {
props: { datum: data }
}
}
const Blog = (datum) => {
const [dark] = useContext(ThemeContext)
return (
<div className={`main ${dark}`}>
<AuthContextProvider>
<Navbar />
<CSSTransition
in={true}
classNames="pagetransitions"
timeout={100}
key={1}
appear={true}
unmountOnExit
>
<div>
<Cookie />
<BlogDetail title={datum.title} datum={datum} />
</div>
</CSSTransition>
</AuthContextProvider>
</div>
)
}
export default Blog;
And my BlogDetail model:
import React, { useState } from 'react';
import styles from "../../styles/blogDetail.module.css"
import timeformatter from "../../functions/timeFormatter"
import Tags from "../Tags";
import Head from "next/head"
import dynamic from 'next/dynamic'
const Favourite = dynamic(() => import("./Favourite"), { ssr: false })
const Comment = dynamic(() => import("./Comment"), { ssr: false })
function BlogDetail(props) {
const data = useState(props.datum)
function createMarkup() {
return { __html: data.text };
}
return (
<div className={styles.blog_text_container}>
<div>
<h1>{data.title}</h1>
<Tags tag={data.tags} />
{data.image_head === null ? (
<span></span>
) : (
<div className={styles.article_detail_image}>
<img className={styles.blog_header_image_detail} alt={data.alt_image_text} src={data.image_head}></img>
</div>
)}
<br></br>
<div dangerouslySetInnerHTML={createMarkup()} />
<br></br>
<span>{data.comments}</span>
<br></br>
<span>Published: {timeformatter(data.created_at)}</span>
<br></br><br></br>
<Favourite id={data.id} favcount={data.favcount} /><br></br>
<Comment id={data.id} /><br></br>
<br></br>
</div>
</div>
)
}
export default BlogDetail
I have tried passing my props individually like the titles, texts. But nodda. I have tried directly rendering the props without including state. Any help would appreciated.

In post page destructure dataum
...other code remains same
const Blog = ({datum}) => {
...other code remains same
In blogdetail page
...other code remains same
function BlogDetail({datum : data}) { // destructuring dataum and naming it as data since you have used data.* in your code
// you donot need useState here
...other code remains same

The issue is probably here
// some code
const Blog = (datum) => {
// some code
Make it to
const Blog = ({datum}) => {
// your code
As explained here
https://nextjs.org/docs/basic-features/data-fetching#simple-example

Related

Data in React Component Not refreshing when Path/Location changes

I have a react app that has a "Bread Crumb Header" component, the data for this component comes from an API end point.
I use the bread crumb header component inside mulitiple components within the app, and based on the current path/window.location the bread crumb componet will get the data from the API and render the correct HTML via JSX.
The problem I have is when I navigate to diffent paths/window.location's within the application the bread crum component data doesn't update.
This is what the bread crumb component looks like:
import React, { useState, useEffect } from 'react';
import API from "../../API";
import { useLocation } from 'react-router-dom';
import { BreadCrumbTitleSection, SubtitleSection, Subtitle } from './breadCrumbHeaderStyle';
import { Breadcrumb } from 'react-bootstrap';
function BreadCrumbHeader() {
const location = useLocation();
const [breadCrumbData, setBreadCrumbData] = useState([]);
const getBreadCrumbData = async () => {
const breadCrumbHeaderResponse = await API.fetchBreadCrumbHeader(location.pathname);
setBreadCrumbData(breadCrumbHeaderResponse);
};
useEffect(() => {
getBreadCrumbData();
}, []);
return (
<div>
<BreadCrumbTitleSection backgroundUrl={breadCrumbData.BreadCrumbBgImage}>
<div className="container">
<div className="row no-gutters">
<div className="col-xs-12 col-xl-preffix-1 col-xl-11">
<h1 className="h3 text-white">{breadCrumbData.BreadCrumbTitle}</h1>
<Breadcrumb>
{breadCrumbData.BreadCrumbLinks.map(breadCrumbLink => (
<Breadcrumb.Item href={breadCrumbLink.LinkUrl} key={breadCrumbLink.Id} active={breadCrumbLink.IsActive}>
{breadCrumbLink.LinkText}
</Breadcrumb.Item>
))}
</Breadcrumb>
</div>
</div>
</div>
</BreadCrumbTitleSection>
<SubtitleSection>
<Subtitle> {breadCrumbData.SubTitle}</Subtitle>
</SubtitleSection>
</div>
);
}
export default BreadCrumbHeader;
and this is an example of how I am using it inside other components:
import React, { useContext } from 'react';
import { useParams } from "react-router-dom";
import { MenuContext } from '../context/menuContext';
import RenderCmsComponents from '../../components/RenderCmsComponents/';
import BreadCrumbHeader from '../../components/BreadCrumbHeader/';
import { CategorySection, CategoryContainer, CategoryItemCard, CategoryItemCardBody, CategoryItemCardImg, CategoryItemTitle, CategoryRow, AddToCartButton, ProductDescription} from './categoryStyle';
function Category() {
const [categoryItems] = useContext(MenuContext);
const { id } = useParams();
const category = categoryItems.find(element => element.CategoryName.toLowerCase() === id.toLowerCase());
var dynamicProps = [];
{
category && category.Products.map(productItem => (
dynamicProps.push(productItem.ProductOptions.reduce((acc, { OptionName, OptionsAsSnipCartString }, i) => ({
...acc,
[`data-item-custom${i + 1}-name`]: OptionName,
[`data-item-custom${i + 1}-options`]: OptionsAsSnipCartString
}), {}))));
}
return (
<div>
<BreadCrumbHeader /> << HERE IT IS
<CategorySection backgroundurl="/images/home-slide-4-1920x800.jpg" fluid>
<CategoryContainer>
<CategoryRow>
{category && category.Products.map((productItem, i) => (
<CategoryItemCard key={productItem.ProductId}>
<CategoryItemTitle>{productItem.ProductName}</CategoryItemTitle>
<CategoryItemCardBody>
<ProductDescription>{productItem.Description}</ProductDescription>
<div>
<CategoryItemCardImg src={productItem.ProductImageUrl} alt={productItem.ProductName} />
</div>
</CategoryItemCardBody>
<AddToCartButton
data-item-id={productItem.ProductId}
data-item-price={productItem.Price}
data-item-url={productItem.ProductUrl}
data-item-description={productItem.Description}
data-item-image={productItem.ProductImageUrl}
data-item-name={productItem.ProductName}
{...dynamicProps[i]}>
ADD TO CART {productItem.Price}
</AddToCartButton>
</CategoryItemCard>
))}
</CategoryRow>
</CategoryContainer>
</CategorySection>
<RenderCmsComponents />
</div>
);
}
export default Category;
I found this post on stack overflow:
Why useEffect doesn't run on window.location.pathname changes?
I think this may be the solution to what I need, but I don't fully understand the accepted answer.
Can someone breakdown to be how I can fix my issue and maybe give me an explaination and possible some reading I can do to really understand how hooks work and how to use them in my situation.
It seems that you should re-call getBreadCrumbData every time when location.pathname was changed. In the code below I've added location.pathname to useEffect dependency list
const location = useLocation();
const [breadCrumbData, setBreadCrumbData] = useState([]);
const getBreadCrumbData = async () => {
const breadCrumbHeaderResponse = await API.fetchBreadCrumbHeader(location.pathname);
setBreadCrumbData(breadCrumbHeaderResponse);
};
useEffect(() => {
getBreadCrumbData();
}, [location.pathname]); // <==== here

How to perform search operation from Navbar when data is recieved from global Context API

I am executing search operation from Navbar component for the data that is present in separate Context API, and the results for the search operation will be presented in another component call Blog, which is using same Context API, but the problem here is search operation is not executing in real time, like when I clear the search bar then It's difficult to set search term in use state hook which is present in context API. So in this case how to solve the problem.
Below is my code from context API
import { BlogContext } from "./BlogContext";
import React from "react";
import { useState } from "react";
export const BlogState = (props) => {
const host = "http://localhost:5000";
const blogInitial = [];
const [blog, setBlog] = useState(blogInitial);
let fetchAllNotes = async () => {
//API call
const response = await fetch(`${host}/api/notes/blog/`, {
method: "GET",
headers: {
"Content-Type": "application/json",
},
});
const json = await response.json();
setBlog(json);
};
const searchFilter = (searchWord) => {
const searchTerm =
blog.filter((note) =>
note.description.toLowerCase().includes(searchWord)
) || ((note) => note.title.toLowerCase().includes(searchWord));
setBlog(searchTerm);
};
return (
<BlogContext.Provider value={{ blog, fetchAllNotes, fil, searchFilter }}>
{props.children}
</BlogContext.Provider>
);
};
Code from Navbar component
import React, { useContext, useState } from "react";
import { Link, useNavigate, useLocation } from "react-router-dom";
import { ThemeContext } from "../context/notes/ThemeContext";
import { BlogContext } from "../context/notes/BlogContext";
export const Navbar = () => {
const { searchFilter, blog } = useContext(BlogContext);
const [searchTerm, setSearchTerm] = useState(blog);
const onChange = (e) => {
if (e.target.value === "") {
window.location.reload(true);
} else {
const search = e.target.value.toLowerCase();
setSearchTerm(search);
searchFilter(searchTerm);
}
};
return (
<div>
<nav
<form className="d-flex mx-2">
<input
onChange={onChange}
className="form-control me-2"
type="search"
placeholder="Search"
aria-label="Search"
/>
<button className="btn btn-success mx-2" type="submit">Clear</button>
</form>
</nav>
</div>
);
};
Code from Blog component
import React, { useContext, useEffect } from "react";
import { ThemeContext } from "../context/notes/ThemeContext";
import { BlogContext } from "../context/notes/BlogContext";
import BlogItem from "./BlogItem";
import { FlexNavbar } from "./FlexNavbar";
const Blog = () => {
const { theme } = useContext(ThemeContext);
const { blog } = useContext(BlogContext);
return (
<>
<div
className={`container bg-${theme} text-${
theme === "dark" ? "light" : "dark"
}`}
>
<FlexNavbar className="" />
<div className="row">
{blog.map((notes) => {
return <BlogItem key={notes._id} note={notes} />;
})}
</div>
</div>
</>
);
};
export default Blog;

How to dispatch to Reducer before React renders component?

React newcomer here.
I'm loading Astronomy Picture of the Day in a component using a loading spinner.
I want the page to get data every time I call it from navbar but it's flashing old data before showing the spinner.
How to avoid this behavior? I don't want to use ComponentWillMount because it's deprecated and I'm using functions.
The component code:
import { useEffect, useContext } from 'react'
import { getApod } from '../context/nasa/NasaActions'
import NasaContext from '../context/nasa/NasaContext'
import Spinner from './layout/Spinner'
function Apod() {
const {loading, apod, dispatch} = useContext(NasaContext)
useEffect(() => {
dispatch({type: 'SET_LOADING'})
const getApodData = async() => {
const apodData = await getApod()
dispatch({type: 'SET_APOD', payload: apodData})
}
getApodData()
}, [dispatch])
const {
title,
url,
explanation,
} = apod
if (loading) { return <Spinner /> }
return (
<div>
<h2>{title}</h2>
<img src={url} className='apod' alt='apod'/>
<p>{explanation}</p>
</div>
)
}
export default Apod
Thanks for your time.
Edit: I deleted the repository. It's already answared correctly.
I suggest you another solution to keep your navbar clean.
You can declare an instance variable loaded using the useRef hook. This variable will be initialized to false and set to true as soon as the apod is dispatched to your store.
import { useContext, useRef } from 'react'
function Apod() {
const {apod, dispatch} = useContext(NasaContext)
const loaded = useRef(false);
const {title, url, explanation} = apod
useEffect(() => {
dispatch({type: 'SET_LOADING'})
const loadApod = async() => {
const apodData = await getApod()
loaded.current = true;
dispatch({type: 'SET_APOD', payload: apodData})
}
loadApod()
}, [dispatch])
if (!loaded.current) { return <Spinner /> }
return (
<div>
<h2>{title}</h2>
<img src={url} className='apod' alt='apod'/>
<p>{explanation}</p>
</div>
)
}
export default Apod;
I had an idea, to clean the object in Context using onClick on the navbar button.
Is this the best way? I don't know but it's working as I wanted.
import NasaContext from '../../context/nasa/NasaContext'
import { useContext } from 'react'
import { Link } from 'react-router-dom'
import logo from './assets/logo.png'
function Navbar() {
const {dispatch} = useContext(NasaContext)
const resetApod = () => {
const pathname = window.location.pathname
if ( pathname !== '/' ) {
dispatch({type: 'SET_APOD', payload: {}})
}
}
return (
<div className="navbar">
<div className="navbar-logo">
<img src={logo} alt='Experimentum'/>
</div>
<div className="navbar-menu">
<Link to='/' onClick={resetApod}>APOD </Link>
<Link to='/about'>ABOUT </Link>
</div>
</div>
)
}
export default Navbar

Front-End Filtering React JS

I have filtered the products and on submitting the search term, am showing the results in a new page using history.push() property.
import React, { useState } from 'react';
import { useSelector } from 'react-redux';
import { IoIosSearch } from 'react-icons/io';
import { useHistory } from "react-router-dom";
import './style.css';
/**
* #author
* #function Search
*/
const Search = (props) => {
const product = useSelector(state => state.product);
let { products , filteredProducts } = product;
const [searchTerm, setSearchTerm] = useState('');
const onChangeSearch = (e) => {
setSearchTerm(e.currentTarget.value);
}
const isEmpty = searchTerm.match(/^\s*$/);
if(!isEmpty) {
filteredProducts = products.filter( function(prod) {
return prod.name.toLocaleLowerCase().includes(searchTerm.toLocaleLowerCase().trim())
})
}
const history = useHistory();
const display = !isEmpty
const handleSubmit =(e) => {
e.preventDefault();
if( !isEmpty ) {
history.push(`/search/search_term=${searchTerm}/`, { filteredProducts })
}
setSearchTerm('');
}
return (
<div>
<form onSubmit={handleSubmit}>
<div className="searchInputContainer">
<input
className="searchInput"
placeholder={'What are you looking for...'}
value={searchTerm}
onChange={onChangeSearch}
/>
<div className="searchIconContainer">
<IoIosSearch
style={{
color: 'black',
fontSize: '22px'
}}
onClick={handleSubmit}
/>
</div>
</div>
</form>
{
display && <div className="searchResultsCont">
{filteredProducts.map((prod, index) => (<div key={index}>{prod.name}</div>))}
</div>
}
</div>
);
}
export default Search
On the new page this is the code :
import React from 'react';
import Layout from '../../components/Layout';
const SearchScreen = ({location}) => {
const products = location.state.filteredProducts;
const show = products.length > 0
return (
<Layout>
<div>
{
show ? products.map((prod, index) => (<div key={index}>{prod.name}</div>)) : <div>No items found</div>
}
</div>
</Layout>
)
}
export default SearchScreen
The problem comes when I copy and paste the URL to another new page, or like when I email others the URL the error becomes " Cannot read property 'filteredProducts' of undefined ". Using this method I understand that the results (filtered products) have not been pushed through the function history.push() that's why it is undefined, how can I make this possible?
I changed the whole aspect to filtering the products from the back-end..
It worked

child/parent problem rendering simple bar chart in react,

"EDITED"
I'm trying to make a very minimalist bar chart.
It doesn't, render. It seems that the child component isn't rendering after the parent component's state has changed.
for example. if I make a change in my code in the MiniChart component, and save the changed through my IDE. the charts will render correctly. but as soon as navigate to another page in my app through my browser and come back to where the charts are, then they won't render.
Any help will be much appreciated.
Child component:
import React, {useState, useEffect} from 'react';
import axios from 'axios';
import {BarChart, Bar} from 'recharts';
const MiniChart = (props) => {
const [apiUrl] = useState("https://api.coingecko.com/api/v3/coins/"+props.id+"/market_chart?vs_currency=usd&days=30&interval=daily");
const [data, setData] = useState([]);
const [msg, setMsg] = useState([]);
const [r, setR] = useState([]);
// fetch data from api
useEffect(() => {
const fetchData = async () => {
if(parseInt(props.rank) < 5){
const result = await axios(apiUrl,);
setData(result.data.prices);
} else {setMsg("TEST : not loaded");}
}
setR(data.map(elem => ({ 'val': elem[1]})));
fetchData();
return()=>{
}
}, [apiUrl, props.rank]);
return (
<div>
<BarChart width={150} height={40} data={r}>
<Bar dataKey='val' fill="green" />
</BarChart>
</div>
)
}
export default MiniChart
Parent component:
import React, { useState} from 'react'
import { FontAwesomeIcon } from "#fortawesome/react-fontawesome";
import { faStar } from "#fortawesome/free-solid-svg-icons";
import { Link, useLocation } from 'react-router-dom';
import Cookies from 'universal-cookie';
import MiniChart from './MiniChart';
const Crypto = (props) => {
const location = useLocation();
const [starColor, setStarColor] = useState(props.defaultStarCol);
const cookies = new Cookies();
const getFavs = cookies.getAll();
// toggle color, re-render, remove or add to cookies
const handleFavToggle = (e) => {
if(starColor === '#ebc934'){
setStarColor('lightgrey');
cookies.remove(props.id, props.id, { path: '/' });
if(location.pathname === '/favorites'){
function refreshPage() {
window.location.reload(false);
}
refreshPage();
}
} else {
setStarColor('#ebc934');
cookies.set(props.id, props.id, { path: '/' });
//console.log(cookies.getAll());
}
}
return (
<div>
<li>
<div className="lidiv">
{props.id in getFavs? //ADD IF LOGGED IN !
<p className="pml"><FontAwesomeIcon style={{color:'#ebc934'}} onClick={handleFavToggle} className="star" icon={faStar}/></p>
: <p className="pml"><FontAwesomeIcon style={{color:'lightgrey'}} onClick={handleFavToggle} className="star" icon={faStar}/></p>}
<p className="pml">{props.rank}</p>
<img className="iconimg" src={props.img} alt=""/>
<p className="pxl coinName"><Link to="/crypto" style={{display: 'block'}}>{props.coin}</Link></p>
<p className="pml">{props.tag}</p>
<p className="pml4">{props.price}</p>
<p className="pml" style={{color: (props.oneday).charAt(0)==='-' ? 'red': 'green'}}>{props.oneday}%</p>
<p className="pxl daycash" style={{color: (props.oneday).charAt(0)==='-' ? 'red': 'green'}}>{props.onedaycurr} </p>
<p className="pxl-4">{props.mcap}M</p>
<MiniChart className="pxl" id={props.id} rank={props.rank}></MiniChart>
</div>
</li>
</div>
)
}
export default Crypto;

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