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Checkbox values are not updating when state is set: ReactJS

I am having an app with two sections. Left section contains the categories and the right section containing the items under it. Under each category, I have the button to select all or unselect all items. I see the state changes happening in the code ( it is pretty printed inside HTML) but the checkbox values are not getting updated. Can someone help?
https://codesandbox.io/s/zealous-carson-dy46k8?file=/src/App.js
export const RightSection = ({ name, apps, json, setJson }) => {
function handleSelectAll(categoryName, type) {
const checked = type === "Select All" ? true : false;
const updated = Object.fromEntries(
Object.entries(json).map(([key, category]) => {
if (category.name !== categoryName) {
return [key, category];
}
const { name, tiles, ...rest } = category;
return [
key,
{
name,
...rest,
tiles: tiles.map((item) => ({
...item,
checked
}))
}
];
})
);
setJson(updated);
}
return (
<>
<div>
<input
type="button"
value={`select all under ${name}`}
onClick={() => handleSelectAll(name, "Select All")}
/>
<input
type="button"
value={`unselect all under ${name}`}
onClick={() => handleSelectAll(name, "Unselect All")}
/>
<h4 style={{ color: "blue" }}>{name} Items</h4>
{apps.map((app) => {
return (
<section key={app.tileName}>
<input checked={app.checked} type="checkbox" />
<span key={app.tileName}>{app.tileName}</span> <br />
</section>
);
})}
</div>
</>
);
};
import { useEffect, useState, useMemo } from "react";
import { SidebarItem } from "./SideBarItem";
import { RightSection } from "./RightSection";
import "./styles.css";
export default function App() {
const dummyJson = useMemo(() => {
return {
cat1: {
id: "cat1",
name: "Category 1",
tiles: [
{
tileName: "abc",
searchable: true,
checked: false
},
{
tileName: "def",
searchable: true,
checked: true
}
]
},
cat2: {
id: "cat2",
name: "Category 2",
tiles: [
{
tileName: "ab",
searchable: true,
checked: true
},
{
tileName: "xyz",
searchable: true,
checked: false
}
]
},
cat3: {
id: "cat3",
name: "Category 3",
tiles: [
{
tileName: "lmn",
searchable: true,
checked: true
},
{
tileName: "",
searchable: false,
checked: false
}
]
}
};
}, []);
const [json, setJson] = useState(dummyJson);
const [active, setActive] = useState(dummyJson["cat1"]);
return (
<>
<div className="container">
<div>
<ul>
{Object.values(json).map((details) => {
const { id, name } = details;
return (
<SidebarItem
key={name}
name={name}
{...{
isActive: id === active.id,
setActive: () => setActive(details)
}}
/>
);
})}
</ul>
</div>
<RightSection
name={active.name}
apps={active.tiles}
{...{ json, setJson }}
/>
</div>
<p>{JSON.stringify(json, null, 2)}</p>
</>
);
}

since you have not updated data of checkbox (in your code) / logic is wrong (in codesandbox) do the following add this function in RightSection
...
function setTick(app, value: boolean) {
app.checked = value;
setJson({...json})
}
...
and onChange in input checkbox
<input
onChange={({ target }) => setTick(app, target.checked)}
checked={app.checked}
type="checkbox"
/>
Codesandbox: see line 25 -> 28 and line 48 in RightSection.tsx are the lines I added
For the two buttons select all and unselect all to update the state of the checkboxes, the data must be synchronized (here you declare active as json independent of each other, this makes the update logic complicated. Unnecessarily complicated, please fix it to sync
const [json, setJson] = useState(dummyJson);
const [activeId, setActiveId] = useState('cat1');
const active = useMemo(() => json[activeId], [json, activeId]);
and update depends:
<SidebarItem
key={name}
name={name}
{...{
isActive: id === activeId,
setActive: () => setActiveId(id)
}}
/>
Codesandbox: line 60 -> 63 and line 81 -> 82 in file App.js
https://codesandbox.io/s/musing-rhodes-yp40fi
the handleOperation function could also be rewritten very succinctly but that is beyond the scope of the question

React checkbox feature with only single selection

I want to figure out whether my code is wrong or a bug. I think there is no problem, but it does not work...
The code I used is:
https://codepen.io/cadenzah/pen/wvwYLgj?editors=0010
class ItemView extends React.Component {
constructor(props) {
super(props)
this.state = {
options: [{
id: 1,
name: "Item 1"
},
{
id: 2,
name: "Item 2"
}],
optionSelected: 2
}
}
toggleCheckbox(e) {
console.log(e.target.id)
if (this.state.optionSelected === e.target.id) {
this.setState({
optionSelected: undefined
})
} else {
this.setState({ optionSelected: e.target.id })
}
}
render() {
return (
<div className="container">
<div className="row">
<ItemList
options={this.state.options}
optionSelected={this.state.optionSelected}
toggleCheckbox={(e) => this.toggleCheckbox(e)} />
</div>
</div>
)
}
}
const ItemList = ({ options, optionSelected, toggleCheckbox }) => {
return (
<div className="col s12">
{
options.map((option, index) => (
<Item
key={index}
option={option}
checked={(optionSelected === (index + 1) ? true : false)}
toggleCheckbox={toggleCheckbox} />
))
}
</div>
)
}
const Item = ({ option, checked, toggleCheckbox }) => {
return (
<div className="card">
<div className="card-content">
<p><label htmlFor={option.id}>
<input
className="filled-in"
type="checkbox"
id={option.id}
onChange={toggleCheckbox}
checked={(checked ? "checked" : "")} />
<span>{option.id}. {option.name}</span>
</label></p>
</div>
</div>
)
}
Code explaination:
React code, with materialize-css used.
It is a simple checkbox feature with multiple items, restricted to select only one item. So, if I check one of them, every item except for what I just selected will be unchecked automatically. If I uncheck what I just checked, every item will stay unchecked.
The core logic is: in <ItemList /> component, there is a conditional props that determines whether each item has to be checked or not. It compares the id, and hand in true or false into its children. That checked props is used in <Item /> component to set the checked attribute of <input>.
Strange thing is, as I set default choice in the initial state, when I just run the application, the check feature works as I expected. But if I click one of them, it does not work.
What is the problem of it?

You can check if the selected option is the checked one like this:
checked={optionSelected === option.id}
And then you simply get it into your input like this:
<input checked={checked} />
Also, make sure to change your state ids into strings (the DOM element id is of type string):
options: [{
id: '1',
name: "Item 1"
},
{
id: '2',
name: "Item 2"
}],
optionSelected: '2'
https://codepen.io/AndrewRed/pen/gOYBVPZ?editors=0010

class ItemView extends React.Component {
constructor(props) {
super(props)
this.state = {
options: [{
id: 1,
name: "Item 1"
},
{
id: 2,
name: "Item 2"
}],
optionSelected: 2
}
}
toggleCheckbox(e) {
this.setState({
optionSelected : e.target.id
})
}
render() {
return (
<div className="container">
<div className="row">
<ItemList
options={this.state.options}
optionSelected={this.state.optionSelected}
toggleCheckbox={(e) => this.toggleCheckbox(e)} />
</div>
</div>
)
}
}
const ItemList = ({ options, optionSelected, toggleCheckbox }) => {
return (
<div className="col s12">
{
options.map((option, index) => (
<Item
key={index}
option={option}
checked={(optionSelected === (index + 1) ? true : false)}
toggleCheckbox={toggleCheckbox}
optionSelected = {optionSelected}
/>
))
}
</div>
)
}
const Item = ({ option, checked, toggleCheckbox,optionSelected }) => {
return (
<div className="card">
<div className="card-content">
<p><label htmlFor={option.id}>
<input
className="filled-in"
type="checkbox"
id={option.id}
onChange={toggleCheckbox}
checked={option.id == optionSelected ? "checked" : ""} />
<span>{option.id}. {option.name}</span>
</label></p>
</div>
</div>
)
}
function tick() {
ReactDOM.render(
<ItemView />,
document.getElementById('root')
);
}
tick()
COPY PASTE AND RUN

e.target.id is a string while index is a number. When you do a === comparison the type is also checked and these are not the same. This results in checked always being false after the initial state (which you set yourself as an int)

Handle Input with Same State Value

I'm building a shopping cart application and I ran into a problem where all my inputs have the same state value. Everything works fine but when I type in one input box, it's the same throughout all my other inputs.
I tried adding a name field to the input and setting my initial state to undefined and that works fine but the numbers don't go through.
How do we handle inputs to be different when they have the same state value? Or is this not possible / dumb to do?
class App extends Component {
state = {
items: {
1: {
id: 1, name: 'Yeezys', price: 300, remaining: 5
},
2: {
id: 2, name: 'Github Sweater', price: 50, remaining: 5
},
3: {
id: 3, name: 'Protein Powder', price: 30, remaining: 5
}
},
itemQuantity: 0
},
render() {
return (
<div>
<h1>Shopping Area</h1>
{Object.values(items).map(item => (
<div key={item.id}>
<h2>{item.name}</h2>
<h2>$ {item.price}</h2>
{item.remaining === 0 ? (
<p style={{ 'color': 'red' }}>Sold Out</p>
) : (
<div>
<p>Remaining: {item.remaining}</p>
<input
type="number"
value={ itemQuantity }
onChange={e => this.setState({ itemQuantity: e.target.value})}
placeholder="quantity"
min={1}
max={5}
/>
<button onClick={() => this.addItem(item)}>Add To Cart</button>
</div>
)}
</div>
))}
</div>
)
}
}

If you are using same state key for all input, All input take value from one place and update to one place. To avoid this you have to use separate state. I suppose you are trying to show input for a list of item.
To achive you can create a component for list item and keep state in list item component. As each component have their own state, state value will not conflict.
Here is an example
class CardItem extends Component {
state = {
number: 0
}
render() {
render (
<input type="text" value={this.state.number} onChange={e => this.setState({ number: e.target.value })} />
)
}
}
class Main extends Component {
render () {
const list = [0,1,2,3,4]
return (
list.map(item => <CardItem data={item} />)
)
}
}

This is a solution which the problem is loosely interpreted, but it does work without having to create another component. As you know, you needed to separate the state of each items in the cart. I did this by dynamically initializing and setting the quantity states of each item. You can see the state changes with this example:
class App extends React.Component {
constructor(props) {
super(props);
this.state = { quantities: {} }
}
componentDidMount() {
let itemIDs = ['1', '2', '3', 'XX']; //use your own list of items
itemIDs.forEach(id => {
this.setState({quantities: Object.assign(this.state.quantities, {[id]: 0})});
})
}
render() {
let list = Object.keys(this.state.quantities).map(id => {
return (
<div>
<label for={id}>Item {id}</label>
<input
id={id}
key={id}
type="number"
value={this.state.quantities[id]}
onChange={e => {
this.setState({quantities: Object.assign(this.state.quantities, {[id]: e.target.value})})
}}
/>
</div>
);
})
return (
<div>
{list}
<div>STATE: {JSON.stringify(this.state)}</div>
</div>
);
}
}
ReactDOM.render(<App/>, 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>
You can modify the state structure to your liking.

Here is how I usually handle this scenario. You say that you get an array of items? Each item object should contain a key to store the value (count in my example). You can use a generic onChange handler to update an individual item in the array. So now, your state is managing the list of items instead of each individual input value. This makes your component much more flexible and it will be able to handle any amount of items with no code changes:
const itemData = [
{ id: 0, count: 0, label: 'Number 1' },
{ id: 1, count: 0, label: 'Number 2' },
{ id: 2, count: 0, label: 'Number 3' },
{ id: 3, count: 0, label: 'Number 4' }
];
class App extends React.Component {
state = {
items: itemData
}
handleCountChange = (itemId, e) => {
// Get value from input
const count = e.target.value;
this.setState( prevState => ({
items: prevState.items.map( item => {
// Find matching item by id
if(item.id === itemId) {
// Update item count based on input value
item.count = count;
}
return item;
})
}))
};
renderItems = () => {
// Map through all items and render inputs
return this.state.items.map( item => (
<label key={item.label}>
{item.label}:
<input
type="number"
value={item.count}
onChange={this.handleCountChange.bind(this, item.id)}
/>
</label>
));
};
render() {
return (
<div>
{this.renderItems()}
</div>
)
}
}
ReactDOM.render(<App />, document.getElementById('root'));
label {
display: block;
}
<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>

You can't use the same state for the both inputs. Try to use a different state for each one like that:
class App extends Component {
state = {
number: ""
}
render() {
return (
<div>
<input
type="number"
value={this.state.number}
onChange={e => this.setState({ number: e.target.value })}
/>
<input
type="number"
value={this.state.number2}
onChange={e => this.setState({ number2: e.target.value })}
/>
</div>
)
}
}

How to control dynamic checkbox in Reactjs?

I tried to control dynamic checkbox rendered from my array. My problem is i have multiple checkbox but i only have one state in my constructor. Is there any others method on how to control dynamic fields/items without
Below is my code :
onAddingItem = (item) =>{
var self = this;
const value = item.target.type === 'checkbox' ? item.target.checked : item.target.value;
var newArray = self.state.product.slice();
if(item.target.checked){
newArray.push(item.target.value);
self.setState({addProducts:value, product:newArray})
} else {
newArray.splice(item.target.value, 1); //remove element
self.setState({addProducts:value, product:newArray}); //update state
}
}
render(){
var self = this;
const {title, photo, photoHeight, photoWidth, showPhoto, editorState, description, editorData, productsList} = this.state;
const product_list = productsList.map((index, i) =>
<tr key={i+1}>
<td>{i+1}</td>
<td>{index.name}</td>
<td>
<div class="checkbox checkbox-circle checkbox-color-scheme">
<label class="checkbox-checked">
<input type="checkbox" value={index.name} checked={self.state.addProducts} onChange={this.onAddingItem}/> <span class="label-text">Add ?</span>
</label>
</div>
</td>
</tr>
);
Whenever i checked one of the checkbox. All the other checkbox also being checked. As you see i want to add the value of the checkbox into an array when its checked and remove the existing value from array when the checkbox is unchecked.

It will be better if you set an isChecked property for your products array.
Here we are:
class App extends React.Component {
constructor(props){
super(props);
this.state = {
productsList :[
{name: 'USS Seawolf class', isChecked: false},
{name: 'USS Skipjack', isChecked: false},
{name: 'USS Lafayette', isChecked: false},
{name: 'USS Ohio class', isChecked: false},
]
}
}
onAddingItem = (i) => (event) => {
this.setState((state, props) => {
state.productsList[i].isChecked = !state.productsList[i].isChecked;
return {
productsList: state.productsList
}
})
}
render() {
let {productsList} = this.state;
return (
<table>
<tbody>
{ productsList.map((product, i) =>{
return(
<tr key={i+1}>
<td>{i+1}</td>
<td>{product.name}</td>
<td>
<div class="checkbox checkbox-circle checkbox-color-scheme">
<label class="checkbox-checked">
<input type="checkbox" value={product.name} checked={product.isChecked} onChange={this.onAddingItem(i)}/> <span class="label-text">Add ?</span>
</label>
</div>
</td>
</tr>
)
})}
</tbody>
</table>
)
}
}
ReactDOM.render( <
App / > ,
document.getElementById('app')
);
<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="app">
<!-- This element's contents will be replaced with your component. -->
</div>
And you can getisChecked elements by filter():
let selectedProductsArray = this.state.productsList.filter((product, i)=>{
return product.isChecked
});

You are setting checked to self.state.addProducts for each checkbox. This property expects a boolean so any truthy value will cause all of the boxes to be checked.
checked should only be true if its value is in self.state.product.
Edit: maybe something like this?
checked={self.state.product.includes(item.value)}

I agree with Emad on adding a property inside each object to control each checkbox, however make sure you don't mutate the state when updating those values.
class App extends React.Component {
constructor(props){
super(props);
this.state = {
productsList: [{ name: "Product A", isAdded: false }, { name: "Product B", isAdded: false }, { name: "Product C", isAdded: false }],
addedProducts: []
}
}
onAddingItem = (item) => {
const isChecked = item.target.checked;
const value = item.target.value;
this.setState(prevState => ({ productsList: prevState.productsList.map(product => product.name === value ? { ...product, isAdded: isChecked } : product) }));
if (isChecked)
this.setState(prevState => ({addedProducts: [...prevState.addedProducts, value] }));
else {
const newAddedProducts = this.state.addedProducts.filter(product => product !== value)
this.setState({ addedProducts: newAddedProducts });
}
}
render() {
const { productsList } = this.state;
const product_list = productsList.map((index, i) =>
<tr key={i + 1}>
<td>{i + 1} - </td>
<td>{index.name}</td>
<td>
<div class="checkbox checkbox-circle checkbox-color-scheme">
<label class="checkbox-checked">
<input type="checkbox" value={index.name} checked={this.state.productsList[i].isAdded} onChange={this.onAddingItem} /> <span class="label-text">Add ?</span>
</label>
</div>
</td>
</tr>
);
return (
<div>
<table>
<tbody>
{product_list}
</tbody>
</table>
<div style={{ marginTop: "20px" }}>Added Products: {this.state.addedProducts.join(', ')}</div>
</div>
)
}
}
ReactDOM.render( <
App / > ,
document.getElementById('app')
);
<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="app">
<!-- This element's contents will be replaced with your component. -->
</div>

Count checked checkboxes in React.js

I'm using a document structure like this
render() {
return (
<div className="MyComponent">
<ul className="">
{parseRecommendations(this.props.recommendations)}
</ul>
</div>
);
}
function parseRecomendations(recommendations) {
return recommendations.map((recommendation, key) => {
return (<Recommendation data={recommendation} key={key} />);
});
}
Where each Recommendation is its own component containing a checkbox
class Recommendation extends Component {
const recommendation = this.props.data;
const pageUrl = recommendation.url;
return (
<li className="article-item" key={key}>
<div className="article-info">
<input type="checkbox" defaultChecked="checked" aria-described-by={recommendation.pii} />
<a className="journal-title" href={pageUrl} id={recommendation.pii}>{recommendation.title}</a>
</div>
</li>
);
I'd like to have a title saying [Download (x) PDFs], where x is the number of selected checkboxes. How do I find the value of x in this case?

You need to store information about whether input is "checked" in your data. Then, simply count items with truthy "checked" flag.
Here is my solution. You should be able to get principle here and modify your code.
const data = [
{ checked: false, value: 'document 1' },
{ checked: true, value: 'document 2' },
{ checked: true, value: 'document 3' },
{ checked: false, value: 'document 4' },
{ checked: false, value: 'document 5' },
];
const Item = props => (
<div>
<input type="checkbox" checked={props.checked} onChange={props.onCheckChange} />
{ props.value }
</div>
)
var Hello = React.createClass({
getInitialState() {
return {
items: this.props.items.concat(),
};
},
onCheckChange(idx) {
return () => {
const items = this.state.items.concat();
items[idx].checked = !items[idx].checked;
this.setState({items});
}
},
totalChecked() {
return this.state.items.filter(props => props.checked).length;
},
render() {
return (
<div>
{ this.state.items.map((props, idx) => (
<Item {...props} key={idx} onCheckChange={this.onCheckChange(idx)} />
)) }
Total checked: { this.totalChecked() }
</div>
);
}
});
ReactDOM.render(
<Hello items={data} />,
document.getElementById('container')
);

If you just want to get the number of selected check-boxes you can try this
let checkedBoxes = document.querySelectorAll('input[name=chkBox]:checked');
Then get the total checked boxes via checkedBoxes.length
Edit:
Instead of querying whole document. You can get the nearest possible parent via getElementsByClassName or getElementById and then apply querySelectorAll on that element.
e.g
let elem = document.getElementsByClassName("MyComponent");
let checkedBoxes = elem.querySelectorAll('input[name=chkBox]:checked');

You also could obtain the total of selected checkboxes by element type. The "console.log(totalSelectedCheckboxes)" will print them when the state of totalSelectedCheckboxes change using useEffect Hook.
import React, { useState, useEffect } from 'react';
const RenderCheckboxes = () => {
const [totalSelectedCheckboxes, setTotalSelectedCheckboxes] = useState(0);
function handleChk() {
setTotalSelectedCheckboxes(document.querySelectorAll('input[type=checkbox]:checked').length);
}
useEffect(() => {
console.log(totalSelectedCheckboxes);
}, [totalSelectedCheckboxes]);
return (<div>
<div>
<input type="checkbox" value={1} onChange={() => handleChk()} />Chk1
</div>
<div>
<input type="checkbox" value={2} onChange={() => handleChk()} />Chk2
</div>
<div>
<input type="checkbox" value={2} onChange={() => handleChk()} />Chk2
</div>
</div>);
}
export default RenderCheckboxes;