Develop Reference

Add onclick or eventListener in insertAdjacentHTML in react-js

I am building a simple react app for learning purpose, I just started learning react-js, I was trying to add paragraph dynamically on user action and it worked perfectly But I want to add an onClick event in insertAdjacentHTML (basically innerHTML).
But onclick event is not working in innerHTML
app.js
const addParagraph = () => {
var paragraphSpace = document.getElementById('container')
paragraphSpace.insertAdjacentHTML('beforeend', `<p>I am dynamically created paragraph for showing purpose<p> <span id="delete-para" onClick={deleteParagraph(this)}>Delete</span>`
}
const deleteParagraph = (e) => {
document.querySelector(e).parent('div').remove();
}
class App extends React.Component {
render() {
return (
<div>
<div onClick={addParagraph}>
Click here to Add Paragraph
</div>
<div id="container"></div>
</div>
)
}
}
What I am trying to do ?
User will be able to add multiple paragraphs and I am trying to add a delete button on every paragraph so user can delete particular paragraph
I have also tried with eventListener like :-
const deleteParagraph = () => {
document.querySelector('#delete').addEventListener("click", "#delete",
function(e) {
e.preventDefault();
document.querySelector(this).parent('div').remove();
})
}
But It said
deleteParagraph is not defined
I also tried to wrap deleteParagraph in componentDidMount() But it removes everything from the window.
Any help would be much Appreciated. Thank You.

Do not manipulate the DOM directly, let React handle DOM changes instead. Here's one way to implement it properly.
class App extends React.Component {
state = { paragraphs: [] };
addParagraph = () => {
// do not mutate the state directly, make a clone
const newParagraphs = this.state.paragraphs.slice(0);
// and mutate the clone, add a new paragraph
newParagraphs.push('I am dynamically created paragraph for showing purpose');
// then update the paragraphs in the state
this.setState({ paragraphs: newParagraphs });
};
deleteParagraph = (index) => () => {
// do not mutate the state directly, make a clone
const newParagraphs = this.state.paragraphs.slice(0);
// and mutate the clone, delete the current paragraph
newParagraphs.splice(index, 1);
// then update the paragraphs in the state
this.setState({ paragraphs: newParagraphs });
};
render() {
return (
<div>
<div onClick={this.addParagraph}>Click here to Add Paragraph</div>
<div id="container">
{this.state.paragraphs.map((paragraph, index) => (
<>
<p>{paragraph}</p>
<span onClick={this.deleteParagraph(index)}>Delete</span>
</>
))}
</div>
</div>
);
}
}

insertAdjecentHTML should not be used in javascripts frameworks because they work on entirely different paradigm. React components are rerendered every time you change a component state.
So you want to manipulate look of your component by changing its state
Solution:
In constructor initialize your component's state which you will change later on button click. Initial state is array of empty paragraphs.
constructor() {
super()
this.state = {
paragraphs:[]
}
}
And alter that state on button click - like this:
<div onClick={addParagraph}>
Add Paragraph function
const addParagraph = () =>{
this.state = this.state.push('New paragraph')
}
Rendering paragraphs
<div id="container">
this.state.paragraphs.map(paragraph =>{
<p>{paragraph}</p>
})
</div>
Additional tip for ReactJS in 2022 - use Functional components instead of Class components

REACT connect 4 game - attempt to reset grid over setState but results in "undefined"

I am trying to create a Connect of 4 game in React as an exercise.
If i want to reset the grid or for displaying player points, a reset of my grid is required rather than simply reloading the entire page.
In this case, dealing with my grid via state is a logical step, but after several attempts and variations, I'm unfortunately lost at the moment
In this variation below, this.state.grid always returns undefined on reset (console.log right after render method begins).
I see that the problem is most likely because in the gridHtml function I am already passing the grid to the state via setState.
If I call this.gridHTML() directly on the reset button, my grid completely disappears.
I am very grateful for any help at this point
import React from 'react';
class Grid extends React.Component {
constructor(props) {
super(props);
this.state = {
player: "red",
isGameOver: false,
gamestarts: false
};
this.findLastEmptyColl = this.findLastEmptyColl.bind(this);
this.onMouseEnter = this.onMouseEnter.bind(this);
this.onMouseLeave = this.onMouseLeave.bind(this);
this.onClick = this.onClick.bind(this);
this.checkForWinner = this.checkForWinner.bind(this);
this.gridHtml = this.gridHtml.bind(this);
this.reset = this.reset.bind(this);
};
/*left out MouseEnter, leave, click and win logic , those work fine and to keep it short */
gridHtml() {
let rows = Array(6).fill(0), cols = Array(7).fill(0);
let grid = rows.map((el, i) => {
return (
<div key={i} className="row">
{cols.map((value, index) => {
return (
<div key={index}
onMouseEnter={this.onMouseEnter}
onMouseLeave={this.onMouseLeave}
onClick={this.onClick}
className="col empty"
data-col={index}
data-row={i}>
</div>
);
})}
</div>
);
});
this.setState({
grid: grid
});
}
componentDidMount() {
this.gridHtml();
}
componentWillMount() {
this.gridHtml();
}
reset() {
this.setState({
grid: this.gridHtml(),
isGameOver: false,
gamestarts: false
})
}
render() {
console.log(this.state.grid);
return (
<>
{!this.state.gamestarts && <h4>Connect 4 - Player {this.state.player} begins!</h4>}
{this.state.gamestarts && <h4>Player {this.state.player} </h4>}
{(this.state.isGameOver && !this.state.gamestarts) && <h4>Player {this.state.player} has won</h4>}
<div id="board">
{this.state.grid}
</div>
<div>
<button style={{margin: "30px"}} onClick={() => {this.reset()}}>Reset</button>
</div>
</>
)
}
}
export default Grid;
Update:
I see that my understanding of React doesn't seem to be properly adjusted yet; in my reset() function, due to the asynchronicity of react, I assume that the dynamic assignment via setState of my grid should actually render automatically?
Again, the problem: when I currently press my reset button, the grid is re-created but the moves, red and yellow, are still on the grid as they were; last I thought of writing a function that instead of creating a new grid removes all CSS classes and data properties related to it - but that would make the whole point of doing something like this with React absurd.
To make it even clearer:
if I extend my reset() function with a setTimeout around setState, right after overwriting my grid, it works?! I can understand why but this right now feels like a hack and I don't want to leave it like this, because this is supposed to be the core competence of React? Hope it helps to understand better
reset () {
this.setState({grid: 'some text ... loading '});
setTimeout(() =>{
this.setState({
grid: this.gridHtml(),
isGameOver: false,
gamestarts: true,
player: "red"
});
}, 1000);
}
Hope somebody can explain?
Many thanks

Your gridHtml() function doesn't return anything so grid is being set to undefined. Try adding a return grid; statement to the end.

unique default state/class to react toggle

I have the below, except currently it's setting the minimize class as default. Toggling works fine, I just would like a unique default class to be show at first before any click has happened. After a click, it would then go between maximize and minimize classes as it does now.
If I could keep the below functionality, and just prevent maximize or minimize classes from being added automatically, this should solve the issue, however anytime I try to remove it breaks.
class ToggleIt extends Component {
constructor(props) {
super(props)
this.state = {
expandedTray: false,
}
this.toggleExpandedTray = this.toggleExpandedTray.bind(this);
}
toggleExpandedTray() {
this.setState({ expandedTray: !this.state.expandedTray, });
}
render() {
return (
<div
className={`something--isi-tray ${this.state.expandedTray ? 'expanded-tray' : 'minimize-tray'}`}
onClick={this.toggleExpandedTray}
>
<div className="something--isi-tray__content">
<h3>{this.props.mainHeadingTitle}</h3>
<div
data-rte-editelement
dangerouslySetInnerHTML={{
__html: DOMPurify.sanitize(this.props.isiContent)
}}
/>
</div>
</div>
)
}
}

Toggling works fine, I just would like a unique default class to be
show at first before any click has happened.
If I correctly understood you could set null as initial value in state, and then
this.state.expandedTray === null ? "some-class" : this.state.expandedTray ? 'expanded-tray' : 'minimize-tray'

Toggle prop passed on one of many targets in ReactJS

Just starting off with ReactJS and have a project where I am showing an accordion of issues and including a details area that is hidden on the start.
There is a button in the accordion bar that should pass a prop to the child element to hide or show them. I have refs on the button and on the details child compoment and added a function to call the function and pass the ref of the details area. I am just not sure how to dynamically change the class hidden on one of many areas and not all of them.
Not sure if putting a class on each element and then learning how to toggle the particular child's class is better or changing the prop to the child.
I can get to the change function but am drawing a blank from there and all the googling shows how to do one element with a grand change of state but I need individual elements.
Here is what I have so far.
Parent
...
<AccordionItem key={item.id} className={iconClass} title={`${item.area}`} expanded={item === 1}>
{
item.issues.map(issue => {
let trim = (issue.issue.length>21) ? `${issue.issue.substring(0,22)}...`: issue.issue;
return (
<div className="issue-bar container-fluid">
<div className="row issue-bar-row">
<span className="issue-title"><img src={CriticalRed} alt="Critical"/> {trim}</span>
<span className="btns">
<button className="btn btn-details" onClick={() => this.showDetail(`details-${issue.id}`)}>Details</button>
</span>
</div>
<IssuesDetails ref={`details-${issue.id}`} issue={issue} shouldHide={true} />
</div>
)
})
}
<div>
</div>
</AccordionItem>
...
Child
export default class IssuesDetails extends Component{
render(){
let issueDetails = classNames( 'issue-details', { hidden: this.props.shouldHide } )
return(
<div className={issueDetails}>
<div className="issues-details-title">
<h3>{this.props.issue.issue}</h3>
</div>
<div className="issues-details-details">
{this.props.issue.details}
</div>
<div className="issues-details-gallery">
<ImageGallery source={this.props.issue.photos} showPlayButton={false} useBrowserFullscreen={false} />
</div>
<button className="btn btn-success">Resolve</button>
</div>
)
}
}
Thanks for any help you provide or places you can send me!

If i'm understanding correctly, you need to be able to swap out shouldHide={true} in certain circumstances. To do this, you'll want your parent component to have a state object which indicates whether they should be hidden or not.
Exactly what this state object looks like depends on what sort of data you're working with. If the issues is a single array, then perhaps the state could be an array of booleans indicating whether each issue is expanded or not. I suspect you may have a more nested data structure, but i can't tell exactly since some of the code was omitted.
So assuming you have an array, it might look like this (i've omitted some things from the render method for brevity):
class Parent extends React.Component {
constructor(props) {
super(props);
this.state = {
hidden: (new Array(props.issues.length)).fill(false),
};
}
showDetail(index) {
let newHidden = this.state.hidden.slice();
newHidden[index] = true;
this.setState({
hidden: newHidden
});
}
render() {
return (
<AccordionItem>
{this.props.issues.map((issue, index) => {
<div>
<button onClick={() => this.showDetail(index))}/>
<IssuesDetails issue={issue} shouldHide={this.state.hidden[index]}/>
</div>
})}
</AccordionItem>
);
}
}

Take a look at these:
https://codepen.io/JanickFischr/pen/xWEZOG
style={{display: this.props.display}}
I think it will help with your problem. If you need more information, please just ask.

React CSSTransitionGroup does not work even with key being set

I have been trying since yesterday to make an animation to my image carousel. As far as I understand, you wrap the content to be animated with the CSSTransitionGroup and make sure it stays in the dom and also specify a unique key to each child of the transition group. I believe I have followed all this yet I see no transition.
One thing worth to mention, While I was trying to get this working I suspected if something could be wrong with the key, so I tried setting the key with a random string. The key would change every-time the state changes, and for some unknown reason I could see the animation. Can someone explain this to me.
I am not sure where I am going wrong, whether the version of transition group or in setting the key to children, No clue !
Below is the code replicating my problem.
var CSSTransitionGroup = React.addons.CSSTransitionGroup
class Images extends React.Component {
constructor(props){
super(props);
this.state = {
showComponent: false,
}
}
componentWillReceiveProps(nextProps){
if (this.props.name === nextProps.showComponentName){
this.setState({
showComponent: true,
})
} else {
this.setState({
showComponent: false,
})
}
}
render() {
if (this.state.showComponent){
return (
<img src={this.props.url} />
)
} else {
return null;
}
}
}
class TransitionExample extends React.Component {
constructor (props) {
super(props);
this.onClick = this.onClick.bind(this);
this.state= {
showComponentName: null,
}
}
onClick(button) {
this.setState({
showComponentName: button.currentTarget.textContent,
})
}
render() {
var imageData = [
"http://lorempixel.com/output/technics-q-c-640-480-9.jpg",
"http://lorempixel.com/output/food-q-c-640-480-8.jpg",
"http://lorempixel.com/output/city-q-c-640-480-9.jpg",
"http://lorempixel.com/output/animals-q-c-640-480-3.jpg"
];
var images = [];
for (var i in imageData) {
i = parseInt(i, 10);
images.push(
<Images url={imageData[i]} showComponentName={this.state.showComponentName} name={imageData[i]} key={imageData[i]} />
);
}
return (
<div>
<div>
<button onClick={this.onClick}>{imageData[0]}</button>
<button onClick={this.onClick}>{imageData[1]}</button>
<button onClick={this.onClick}>{imageData[2]}</button>
<button onClick={this.onClick}>{imageData[3]}</button>
</div>
<div className="transitions">
<CSSTransitionGroup
transitionName="viewphoto"
transitionEnterTimeout={2000}
transitionLeaveTimeout={2000}
transitionAppearTimeout={2000}
transitionAppear={true}
transitionEnter={true}
transitionLeave={true}>
{images}
</CSSTransitionGroup>
</div>
</div>
);
}
}
ReactDOM.render(
<TransitionExample />,
document.getElementById('container')
);
I am also providing the link to the example on jsfiddle

The problem with your code is that images is always an array of elements that don't mount/unmount. The correct approach for this is to change the child. For example, if you substitute the return of the render method of your fiddle with this:
return (
<div>
<div>
<button onClick={this.onClick}>{imageData[0]}</button>
<button onClick={this.onClick}>{imageData[1]}</button>
<button onClick={this.onClick}>{imageData[2]}</button>
<button onClick={this.onClick}>{imageData[3]}</button>
</div>
<div className="transitions">
<CSSTransitionGroup
transitionName="viewphoto"
transitionEnterTimeout={2000}
transitionLeaveTimeout={2000}
transitionAppearTimeout={2000}
transitionAppear={true}
transitionEnter={true}
transitionLeave={true}>
<img src={this.state.showComponentName} key={this.state.showComponentName}/>
</CSSTransitionGroup>
</div>
</div>
);
The animation works! Using a simple img instead of your Images component and giving it the image url (this only works when you have clicked a button, showComponentName should be initialized to show the first image). You could also use a custom component of course, but the point here is that the children elements of CSSTransitionGroup must be changed if you want the animation to trigger because otherwise you are always rendering the same four Images components no matter whether they return the img or not. You might want to check out react-css-transition-replace since it usually works better when it comes to replacing.