Text area not rendering React - javascript

I'm not sure why my text area isn't rendering if someone could suggest what I'm missing or what I've done wrong I'd be forever grateful.
I'm not sure whether maybe I should try rending it in the App.js file.
I'm also sure I don't need to import the App.js file to the CardCheck.js because it's a child.
import "./App.css";
import React from "react";
import CardCheck from "./CardCheck";
class App extends React.Component() {
state = {
cardNumber: "",
};
handleChange = (event) => {
this.setState({ cardNumber: event.target.value });
};
handleClick = () => {
const { cardNumber } = this.state;
this.setState({
cardNumber: "",
});
};
render() {
const { cardNumber } = this.state;
return (
<div className="App">
<h1>Taken Yo Money</h1>
<CardCheck
cardNumber={cardNumber}
handleChange={this.handleChange}
handleClick={this.handleClick}
/>
</div>
);
}
}
export default App;
function CardCheck(props) {
const { cardNumber, handleChange, handleClick } = props;
return (
<div className="TweetInput">
<div className="bar-wrapper"></div>
<textarea onChange={handleChange} value={cardNumber}></textarea>
<footer>
<button onClick={handleClick}>Enter Card Details</button>
</footer>
</div>
);
}
export default CardCheck;

Remove the parentheses from class App extends React.Component(). It should be
class App extends React.Component {
//rest of the code
}
``

You need to replace class App extends React.Component() with class App extends Component {
The Component is imported from import React, { Component } from "react";
It should fix the rendering issue

Related

Using button in one component to render another component in main (App) component

I am trying to display/hide one component which is ItemMain and which is imported to the main App component using button in another component which is NavLogoNew. I tried to do this in many different ways but it looks like the button doesn't know if it's clicked, when I change true/false manually it works. In web I found a lot of stuff about situations when only two components are involved, but nothing like this. My code:
App
import React from 'react';
import './App.css';
import { tsPropertySignature } from '#babel/types';
import { statement } from '#babel/template';
import NavBar from './../Components/Navigation/NavBar/NavBar.js';
import ItemMain from './../Components/Item/ItemMain/ItemMain.js';
import ItemList from './../Components/Item/ItemList/ItemList.js';
import NavButtonTop from './../Components/Navigation/NavButton/NavButtonTop/NavButtonTop.js';
import NavLogoNew from './../Components/Navigation/NavButton/NavButtonNew/NavLogoNew.js';
class App extends React.Component {
constructor(props) {
super(props);
this.state = {
visible: false
};
this.handleClick = this.handleClick.bind(this);
}
handleClick() {
this.setState({
visible: !this.visible
})
}
render() {
return (
<div className="App">
<NavBar />
{this.state.visible ? <ItemMain /> : null}
<ItemList />
<NavButtonTop name='UP'/>
</div>
);
}
}
export default App;
NavLogoNew:
import React from 'react';
import './NavLogoNew.css';
import ItemMain from './../../../Item/ItemMain/ItemMain.js'
class NavLogoNew extends React.Component {
render() {
return (
<button
className='NavLogoNew'
onClick={this.props.click}
>
{this.props.name}
</button>
);
}
}
export default NavLogoNew;
Your handleClick function is lacking something
use !this.state.visible so change from the below
handleClick(){
this.setState({
visible: !this.visible
})
}
to
handleClick = () => {
this.setState({
visible: !this.state.visible
})
}
pass the handleClick function to the NavLogoNew as follows
<NavLogoNew onClick = {this.handleClick} />
inside of the NavLogoNew component you should invoke it as follows
class NavLogoNew extends React.Component {
render() {
return (
<button
className='NavLogoNew'
onClick={() => this.props.onClick()}
>
{this.props.name}
</button>
);
}
}

How to change className?

So I keep div element in my state. I want to change it's className in response to onClick event. I know I could do it with event.target.className but the code below is only the sample of a biggest application and it's not possible to use it there. As a resultant from changeClass function I get
"TypeError: Cannot assign to read only property 'className' of object '#'".
So I wonder is there any other way to do it?
import React, { Component } from "react";
import "./styles/style.css";
class App extends Component {
constructor(props) {
super(props);
this.state = {
myDiv: [
<div
id="firstDiv"
key={1}
className={"first"}
onClick={this.changeClass}
/>
]
};
}
changeClass = () => {
this.setState(prevState => {
return { myDiv: (prevState.myDiv[0].props.className = "second") };
});
};
render() {
return <div>{this.state.myDiv.map(div => div)}</div>;
}
}
export default App;
Don't put your jsx in state. only add className and state and onChangeClass use this.stateState to update className.
import React, { Component } from "react";
import "./styles/style.css";
class App extends Component {
constructor(props) {
super(props);
this.state = {
className:"first"
};
}
changeClass = () => {
this.setState({ classNmae: "two" });
};
render() {
return <div>
<div
id="firstDiv"
className={this.state.className}
onClick={this.changeClass}
/>
</div>;
}
}
export default App;
there's a simpler option try this:
import React, { Component } from "react";
import "./styles/style.css";
class App extends Component {
constructor(props) {
super(props);
this.state = {
className: "first"
};
}
changeClass = () => {
this.setState({className: "second"});
};
render() {
return <div
id="firstDiv"
className={this.state.className}
onClick={this.changeClass}>
</div>;
}
}
export default App;
You can use Hooks if you use a React version upper than 16.8
import React, { useState } from "react"
import "./styles/style.css"
const App = () => {
const [myClass, setMyClass] = useState("first")
const changeClass = () => {
setMyClass("second")
}
render() {
return <div
id="firstDiv"
className={myClass}
onClick={changeClass}>
</div>;
}
}
export default App

React.js search bar always fetches the same content

I'm building a search engine with React.js, where I can look for GIPHY gifs using their API. Everytime I type a word(any word), it always loads the same gifs and when I erase and write another word, the gifs don't update.
index.js:
import React from 'react'; //react library
import ReactDOM from 'react-dom'; //react DOM - to manipulate elements
import './index.css';
import SearchBar from './components/Search';
import GifList from './components/SelectedList';
class Root extends React.Component { //Component that will serve as the parent for the rest of the application.
constructor() {
super();
this.state = {
gifs: []
}
this.handleTermChange = this.handleTermChange.bind(this)
}
handleTermChange(term) {
console.log(term);
let url = 'http://api.giphy.com/v1/gifs/search?q=${term.replace(/\s/g, '+')}&api_key=aOfWv08Of7UqS6nBOzsO36NDvwYzO6io';
fetch(url).
then(response => response.json()).then((gifs) => {
console.log(gifs);
this.setState({
gifs: gifs
});
});
};
render() {
return (
<div>
<SearchBar onTermChange={this.handleTermChange} />
<GifList gifs={this.state.gifs} />
</div>
);
}
}
ReactDOM.render( <Root />, document.getElementById('root'));
search.js
import React, { PropTypes } from 'react'
import './Search.css'
class SearchBar extends React.Component {
onInputChange(term) {
this.props.onTermChange(term);
}
render() {
return (
<div className="search">
<input placeholder="Enter text to search for gifs!" onChange={event => this.onInputChange(event.target.value)} />
</div>
);
}
}
export default SearchBar;
Giflist:
import React from 'react';
import GifItem from './SelectedListItem';
const GifList = (props) => {
console.log(props.gifs);
const gifItems = props.gifs && props.gifs.data && props.gifs.data.map((image) => {
return <GifItem key={image.id} gif={image} />
});
return (
<div className="gif-list">{gifItems}</div>
);
};
export default GifList;
GifItem:
import React from 'react';
const GifItem = (image) => {
return (
<div className="gif-item">
<img src={image.gif.images.downsized.url} />
</div>
)
};
export default GifItem;
I can't seem to find where is the issue here. Is it because of this.handleTermChange = this.handleTermChange.bind(this) and there is no "update" state after?
Any help is welcome :) Thanks!
Its because, you are not putting the term value entered by user in the url, all the time you hit the api with static value term, here:
'http://api.giphy.com/v1/gifs/search?q=${term.replace(/\s/g, '+')}&api_key=aOfWv08Of7UqS6nBOzsO36NDvwYzO6io';
Replace ' by ' (tick), like this:
let url = `http://api.giphy.com/v1/gifs/search?q=${term.replace(/\s/g, '+')}&api_key=aOfWv08Of7UqS6nBOzsO36NDvwYzO6io`;
Check MDN Doc for more details about Template Literals.

React.js - How to implement a function in a child component to unmount another child from the same parent, and mount another component on it's place?

For example, a component like this:
import React, { Component } from 'react';
import BodyContent from './BodyContent';
import BottomOne from './BottomOne';
import BottomTwo from './BottomTwo';
class App extends Component {
render() {
return (
<div className="App">
<BodyContent />
<BottomOne />
</div>
);
}
}
export default App;
I want to implement a function on BodyContent that unmount BottomOne and mounts BottomTwo instead, so when I activate the function, the code is reestructured to this:
import React, { Component } from 'react';
import BodyContent from './BodyContent';
import BottomOne from './BottomOne';
import BottomTwo from './BottomTwo';
class App extends Component {
render() {
return (
<div className="App">
<BodyContent />
<BottomTwo />
</div>
);
}
}
export default App;
I'm very new to React, so if there's a better way to do it, I'm open to suggestions, but I really need that end result, a function on BodyContent that unmounts BottomOne and mounts BottomTwo.
You can maintain a state which tells which component to render. Something roughly like this
import React, { Component } from 'react';
import BodyContent from './BodyContent';
import BottomOne from './BottomOne';
import BottomTwo from './BottomTwo';
class App extends Component {
changeBottomComponent = (comp) => {
this.setState({ showBottom: comp})
}
render() {
return (
<div className="App">
<BodyContent changeBottomComponent={this.changeBottomComponent}/>
{this.state.showBottom === 1 ? <BottomOne /> : <BotttomTwo />}
</div>
);
}
}
export default App;
To achieve that maintain a state variable in parent component (some kind of identifier for component) and use that state variable to render different component.
Along with that you also need to pass a function from parent to child and use that function to update the parent state value.
Like this:
class App extends Component {
constructor(){
super();
this.state={
renderOne: true,
}
this.update = this.update.bind(this);
}
update(){
this.setState({renderOne: false})
}
render() {
return (
<div className="App">
<BodyContent update={this.update}/>
{this.state.renderOne? <BottomOne /> : <BottomTwo/> }
</div>
);
}
}
Now inside BodyContent component call this.props.update() to render another component.
You can use state or props to render different components.
Example:
import React, {
Component
}
from 'react';
import BodyContent from './BodyContent';
import BottomOne from './BottomOne';
import BottomTwo from './BottomTwo';
class App extends Component {
constructor(props) {
super(props);
this.state = {
decider: false
};
}
render() {
const bottomContent = this.state.decider === true ? <BottomOne /> : <BottomTwo />;
return (
<div className="App">
<BodyContent />
{ bottomContent }
</div>
);
}
}
export
default App;
You can also directly use the components in the state and render them. Could be more flexible this way.
const BottomOne = () => <div>BottomOne</div>;
const BottomTwo = () => <div>BottomTwo</div>;
class Example extends React.Component {
constructor() {
super();
this.state = { show: BottomOne };
this.toggleComponent = this.toggleComponent.bind(this);
}
toggleComponent() {
// Use whatever logic here to decide.
let show = BottomOne;
if (this.state.show === BottomOne) {
show = BottomTwo;
}
this.setState({ show });
}
render() {
return (
<div>
<button onClick={this.toggleComponent}>Change</button>
<this.state.show />
</div>
);
}
}
ReactDOM.render(<Example />, document.getElementById('root'));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="root"></div>

State is not getting updated

I'm currently using Flickr api to make a Simple Image Carousel and facing a problem where my state does not get updated or rendered whenever I click the button.
Here is my index.js
import React, { Component } from 'react';
import ReactDOM from 'react-dom';
import axios from 'axios';
import _ from 'lodash';
import Photo from './components/photo';
const urlArr = [];
const apiKey = "API";
const userId = "ID";
const url = `https://api.flickr.com/services/rest/?method=flickr.people.getPublicPhotos&api_key=${apiKey}&user_id=${userId}&format=json&nojsoncallback=1`;
class App extends Component {
constructor(props) {
super(props);
this.state = { urlArr: [] };
axios.get(url)
.then((photoData) => {
_.forEach(photoData.data.photos.photo, (photo) => {
urlArr.push(`https://farm6.staticflickr.com//${photo.server}//${photo.id}_${photo.secret}_z.jpg`);
});
this.setState({ urlArr });
});
}
render() {
return (
<div>
<Photo urls={this.state.urlArr}/>
</div>
);
}
};
ReactDOM.render(<App/>, document.querySelector('.container'));
and here is my photo.js
import React, { Component } from 'react';
import NextButton from './nextButton';
import PrevButton from './prevButton';
class Photo extends Component {
constructor(props) {
super(props);
this.state = { idx: 0 };
this.nextImg = this.nextImg.bind(this);
}
nextImg() {
this.setState({ idx: this.state.idx++ });
}
render() {
if (this.props.urls.length === 0) {
return <div>Image Loading...</div>
}
console.log(this.state);
return(
<div>
<PrevButton />
<img src={this.props.urls[this.state.idx]}/>
<NextButton onClick={this.nextImg}/>
</div>
);
}
}
export default Photo;
and my nextButton.js (same as prevButton.js)
import React from 'react';
const NextButton = () =>{
return (
<div>
<button>next</button>
</div>
);
};
export default NextButton;
Since I'm fairly new to React, I'm not quite sure why my this.state.idx is not getting updated when I click on the next button (Seems to me that it is not even firing nextImg function either). If anyone can give me a help or advice, that would really appreciated.
Thanks in advance!!
Update your NextButton. Use the event within your presentational component.
<NextButton next={this.nextImg}/>
And the NextButton component should looks like this.
import React from 'react';
const NextButton = (props) =>{
return (<div>
<button onClick={props.next}>next</button>
</div>
);
};
The problem lies with this piece of code:
axios.get(url)
.then((photoData) => {
_.forEach(photoData.data.photos.photo, (photo) => {
urlArr.push(`https://farm6.staticflickr.com//${photo.server}//${photo.id}_${photo.secret}_z.jpg`);
});
this.setState({ urlArr });
});
this refers to the axios.get callback scope and not the Component. You can define another variable called self or something that makes more sense to you and call self.setState().
See this question for a similar problem: Javascript "this" scope

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