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Passing an object Id by submit button in order to find and change value in array after submiting (react)

I want to update a value of an object nested in array after choosing new date from select button and then submiting it in order to change it.
The button (select) is nested with a rendered array object invoice in Accordion from material ui and is supposed to change a date (for now a year only) and save it while comparing its Id number.
I have two components : sideBar and simpleForm
const SideBar = ({ className }) => {
const [invoices, setInvoice] = useState([
{ label: 'Test', invoiceDate: '2021', id: 0 },
{ label: 'Test', invoiceDate: '2022', id: 1 },
{ label: 'Test', invoiceDate: '', id: 2 },
])
const addInvoiceDate = (date, invoice) => {
setInvoice(
invoices.map((x) => {
if (x.id === invoice.id)
return {
...x,
invoiceDate: date,
}
return x
})
)
}
return (
<>
<Wrapper>
<S.MainComponent>
<div>
{invoices.map((invoice) => {
return (
<Accordion>
<AccordionSummary expandIcon={<ExpandMoreIcon />}>
<div key={invoice.id}>
{invoice.label}
{invoice.invoiceDate}
</div>
</AccordionSummary>
<AccordionDetails>
<SimpleForm addInvoiceDate={addInvoiceDate} />
</AccordionDetails>
</Accordion>
)
})}
</div>
</S.MainComponent>
</Wrapper>
</>
)
}
Simple Form :
const SimpleForm = ({ addInvoiceDate }) => {
const [date, setDate] = useState('')
const handleSubmit = (e) => {
e.preventDefault()
addInvoiceDate(date)
}
function range(start, end) {
return Array(end - start + 1)
.fill()
.map((_, placeholder) => start + placeholder)
}
const Years = range(2021, 4000)
const Options = []
Years.forEach(function (element) {
Options.push({ label: element, value: element })
})
return (
<form onSubmit={handleSubmit}>
<select value={date} required onChange={(e) => setDate(e.target.value)}>
{Options.map((option) => (
<option value={option.value}>{option.label}</option>
))}
</select>
<input type='submit' value='Save' />
</form>
)
}
My problem is, i have no clue how can i succesfully pass an id number of array object to addInvoiceDate (change invoice date)in order to find it in orginal array, compare it and then submit new value. I was testing adding a new object with a new year value and it worked, but in that case i dont have to find an id of object. Its a little bit harder if i want actually find a previous one and update it through comparing id.
Any ideas how it should be done ? Probably i overlooked something or dont have enough expierience yet :)

How about this
<SimpleForm addInvoiceDate={(date) => addInvoiceDate(date, invoice)} date={invoice.invoiceDate}/> in SideBar's return
Remove the state from SimpleForm as we now have a date prop instead
<select value={date} required onChange={(e) => addInvoiceDate(e.target.value)}> in SimpleForm's return
Please leave a comment if there are questions

How do I add an list element seperately to 2 lists?

I am pretty new to react. So I have one parent component which has two child components. These 2 children are the lists that should be displayed. So far I figured out how to transfer the data between two lists by checking the status property of the data. I am not able to understand how to add data into the separate lists and edit them since the parent component renders the 2 lists. Can anyone explain how to add and edit new data that the user will enter? Should I create new states and props on the Items page or should I create them on the child component page? I am pretty confused.
import React,{useState,useEffect} from 'react'
import { Completed } from './Completed'
import { Pending } from './Pending'
export const Items = () => {
const [items,setItems]=useState([
{
id: 1,
title:'Workout',
status:'Pending'
},
{
id: 2,
title:'Read Books',
status:'Pending'
},
{
id: 3,
title:'Cook Pizza',
status:'Pending'
},
{
id: 4,
title:'Pay Bills',
status:'Completed'
},
{
id: 5,
title:' Watch Big Short',
status:'Completed'
},
{
id: 6,
title:' Make nutrition Plan',
status:'Pending'
}
])
const updateStatus=(id,newStatus)=>{
let allItems=items;
allItems=allItems.map(item=>{
if(item.id===id){
console.log('in here')
item.status=newStatus;
}
return item
})
setItems(allItems)
}
return (
<div class="items">
<Pending items={items} setItems={setItems} updateStatus={updateStatus}/>
<Completed items={items} setItems={setItems} updateStatus={updateStatus}/>
</div>
)
}
import React from 'react'
export const Pending = ({items,setItems,updateStatus}) => {
return (
<div className="pending">
<h1>LEFT</h1>
{
items && items.map(item=>{
if(item && item.status==='Pending')
return <><p className="item" key={item.id}>{item.title} <button className="mark_complete" key={item.id} onClick={()=>{updateStatus(item.id,'Completed')}}>Move Right</button></p></>
})
}
</div>
)
}
import React from 'react'
export const Completed = ({items,setItems,updateStatus}) => {
return (
<div className="completed">
<h1>RIGHT</h1>
<form onSubmit={this.addItem}>
<input placeholder="enter task">
</input>
<button type="submit">add</button>
</form>
{
items && items.map(item=>{
if(item && item.status==='Completed')
return <><p className="item" key={item.id}>{item.title} <button className="mark_pending" key={item.id} onClick={()=>{updateStatus(item.id,'Pending')}}> Move Left</button></p> </>
})
}
</div>
)
}
I have attached the 3 components which are Items, Pending and Completed above.

It's almost always better to have the state in the parent and pass down props to the children. So you want to keep your items state where it is. You can create an addItem function and pass it down as a prop to any child.
I don't think it makes sense to be able to add items from both lists since new items should be 'Pending'. So I would recommend that you put your add form in a new component AddItem which would be a third child of Items. Once AddItem calls the addItem function from props, that item will get saved to the state in items and it will show up in the Pending list automatically.
If all new items have status 'Pending' then the only information that we should need to add an item is the title of the task.
This function goes in Items:
const addItem = (title) => {
// set state using a callback function of current state
setItems((current) => {
// the highest number of all current ids, or 0 if empty
const maxId = current.reduce((max, o) => Math.max(max, o.id), 0);
// the next id is the max plus 1
const id = maxId + 1;
// add new item to the current - concat won't mutate the array
return current.concat({
id,
title,
status: "Pending"
});
});
};
Your AddItem component uses a controlled input to create the text for the new item.
export const AddItem = ({ addItem }) => {
const [title, setTitle] = useState("");
const handleSubmit = (e) => {
// prevent form submission from reloading the page
e.preventDefault();
// call the addItem function with the current title
addItem(title);
// clear the form
setTitle("");
};
return (
<form onSubmit={handleSubmit}>
<input
placeholder="enter task"
value={title}
onChange={(e) => setTitle(e.target.value)}
/>
<button type="submit">add</button>
</form>
);
};
Inside the return of Items, include your form:
<AddItem addItem={addItem} />
Unrelated to the question at hand, there are a few other improvements that you can make to your code.
Your updateStatus function actually mutates the current item. You should instead create a new object for the changed item by copying everything except the status.
You are getting warnings about unique keys because the key must be on the outermost component inside the .map(). You put a fragment <> outside the <p> which has the key, so remove the fragment.
In my opinion the filtering of which item goes in each list should be done by the parent. Your Completed and Pending components are extremely similar. You should combine them into one component. Everything that is different between the two, such as texts and class names, can be controlled by the props that you pass in.
import React, { useState } from "react";
export const ItemsList = ({
items,
title,
className,
buttonText,
onClickButton
}) => {
return (
<div className={className}>
<h1>{title}</h1>
{items.map((item) => (
<p className="item" key={item.id}>
<span className="item_title">{item.title}</span>
<button
className="move_item"
key={item.id}
onClick={() => {
onClickButton(item.id);
}}
>
{buttonText}
</button>
</p>
))}
</div>
);
};
// example of how to compose components
// this keeps the same setup that you had before, but without repeated code
export const Completed = ({ items, updateStatus }) => {
return (
<ItemsList
title="RIGHT"
buttonText="Move Left"
className="completed"
items={items.filter((item) => item.status === "Completed")}
onClickButton={(id) => updateStatus(id, "Pending")}
/>
);
};
export const AddItem = ({ addItem }) => {
const [title, setTitle] = useState("");
const handleSubmit = (e) => {
// prevent form submission from reloading the page
e.preventDefault();
// call the addItem function with the current title
addItem(title);
// clear the form
setTitle("");
};
return (
<form onSubmit={handleSubmit}>
<input
placeholder="enter task"
value={title}
onChange={(e) => setTitle(e.target.value)}
/>
<button type="submit">add</button>
</form>
);
};
export const Items = () => {
const [items, setItems] = useState([
{
id: 1,
title: "Workout",
status: "Pending"
},
{
id: 2,
title: "Read Books",
status: "Pending"
},
{
id: 3,
title: "Cook Pizza",
status: "Pending"
},
{
id: 4,
title: "Pay Bills",
status: "Completed"
},
{
id: 5,
title: " Watch Big Short",
status: "Completed"
},
{
id: 6,
title: " Make nutrition Plan",
status: "Pending"
}
]);
const addItem = (title) => {
// set state using a callback function of current state
setItems((current) => {
// the highest number of all current ids, or 0 if empty
const maxId = current.reduce((max, o) => Math.max(max, o.id), 0);
// the next id is the max plus 1
const id = maxId + 1;
// add new item to the current - concat won't mutate the array
return current.concat({
id,
title,
status: "Pending"
});
});
};
const updateStatus = (id, newStatus) => {
setItems((current) =>
// arrow function without braces is an implicit return
current.map((item) =>
item.id === id
? // copy to new item if id matches
{
...item,
status: newStatus
}
: // otherwise return the existing item
item
)
);
};
return (
<div className="items">
<AddItem addItem={addItem} />
{/* can set the props on ItemsList here */}
<ItemsList
title="LEFT"
buttonText="Move Right"
className="pending"
items={items.filter((item) => item.status === "Pending")}
// create a function that just takes the `id` and sets the status to "Completed"
onClickButton={(id) => updateStatus(id, "Completed")}
/>
{/* or do it in a separate component */}
<Completed items={items} updateStatus={updateStatus} />
</div>
);
};
export default Items;
Code Sandbox Link

Can't render elements from mutated Array - React

So, the problem I've faced is that when I click delete button at any index it just deletes last element
for example, if I press first delete button, it should remove first input and the delete button, but what it does is that it deletes last element only... What could be wrong?
function App() {
const [names, setNames] = React.useState([
"First",
"Second",
"third",
"fourth"
]);
const onChange= (index: number, editedName: string) => {
const mutatedNames = [...names];
mutatedNames[index] = editedName;
setNames(mutatedNames);
};
function onDelete(index: number) {
const nameArr = [...names];
nameArr.splice(index, 1);
setNames(nameArr);
}
return (
<div>
{names.map((name, index) => (
<ChildComponent
key={index}
name={name}
index={index}
onChange={onChange}
onDelete={onDelete}
/>
))}
</div>
);
}
const Child = React.memo(
({ name, index, onChange, onDelete }) => {
return (
<div>
<input
onChange={(event) => onChange(index, event.target.value)}
/>
<button onClick={() => onDelete(index)}>delete</button>
</div>
);
}
);

You are using a partially controlled input, this is almost never a good idea.
Make it fully controlled like so:
<input
value={name}
onChange={(event) => onChange(index, event.target.value)} />
I suggest you read the official guidelines about Forms and Controlled Components and the article about the uncontrolled scenario.

Updating React state with Hooks and tags

I'm having a syntax doubt on how to update React state using hooks in 2 situations.
1) I have a state called company and a form that fills it up. In contact section, there are two inputs referring to the company employee (name and telephone number). But if the company has more than one employee to be contacted, there is an "Add More Contact" button, which must duplicate the same inputs (of course, aiming to a second contact). How can I do that? I mean, to generate another index in the array "contacts" inside the state, increment the totalOfContacts inside the object that has that array and create the input tags so user can type the second contact's data?
2) When I type any inputs, the code triggers the handleChange function. The "name" and "city" already update the state because they are simple states. But how can I update the contact name and his telephone number, since they are part of an index of an array inside the state?
The code below is already working and my 2 questions are exactly the two commented lines (lines 20 and 29).
The "Save" button simply console.log the results so we can monitor them.
Thanks for now.
import React, { useState, useEffect } from "react";
export default () => {
const [company, setCompany] = useState({
name: "", city: "",
contact: {
totalOfContact: 1,
contacts: [
{id: 0, contactName: "", telephoneNumber: ""}
]
}
})
useEffect(() => {
console.log("teste");
})
const handleChange = item => e => {
if (item === "contactName" || "telephone") {
// How can I set company.contact.contacts[<current_index>].contactName/telephoneNumber with the data typed?
} else {
setCompany({ ...company, [item]: e.target.value })
}
}
const handleClick = (e) => {
e.preventDefault();
if (e.target.value === "add") {
// How can I set company.contact.totalOfContact to 2 and create one more set of inputs tags for a second contact?
} else {
console.log(`The data of the company is: ${company}`);
}
}
return (
<div>
<form>
<h3>General Section</h3>
Name: <input type="text" onChange = {handleChange("name")} value = {company.name} />
<br />
City: <input type="text" onChange = {handleChange("city")} value = {company.city} />
<br />
<hr />
<h3>Contacts Section:</h3>
Name: <input type="text" onChange = {handleChange("contactName")} value = {company.contact.contacts[0].name} />
Telephone Numer: <input type="text" onChange = {handleChange("telephone")} value = {company.contact.contacts[0].telephoneNumber} />
<br />
<br />
<button value = "add" onClick = {(e) => handleClick(e)} >Add More Contact</button>
<br />
<br />
<hr />
<button value = "save" onClick = {(e) => handleClick(e)} >Save</button>
</form>
</div>
)
}

To update the state value, you can use functional setState,
const handleChange = item => e => {
//Take the value in a variable for future use
const value = e.target.value;
if (item === "contactName" || "telephone") {
setCompany(prevState => ({
...prevState,
contact: {...prevState.contact, contacts: prevState.contact.contacts.map(c => ({...c, [item]: value}))}
}))
} else {
setCompany({ ...company, [item]: e.target.value })
}
}
To add new set of input on the click of button you can do this,
const handleClick = (e) => {
e.preventDefault();
//This is new set of input to be added
const newSetOfInput = {id: company.contact.contacts.length, contactName: "", telephoneNumber: ""}
if (e.target.value === "add") {
// How can I set company.contact.totalOfContact to 2 and create one more set of inputs tags for a second contact?
setCompany(prevState => ({
...prevState,
contact: {...prevState.contact, contacts: prevState.contact.contacts.concat(newSetOfInput), totalOfContact: prevState.contact.contacts.length + 1}
}))
} else {
console.log(`The data of the company is: ${company}`);
}
}
Finally you need to iterate over your contacts array like,
{company.contact.contacts && company.contact.contacts.length > 0 && company.contact.contacts.map(contact => (
<div key={contact.id}>
Name: <input type="text" onChange = {handleChange("contactName")} value = {contact.contactName} />
<br/>
Telephone Numer: <input type="text" onChange = {handleChange("telephoneNumber")} value = {contact.telephoneNumber} />
</div>
))}
Demo
Note: You should use block elements like div instead of breaking the line using <br/>

To answer your question let us scope down this problem to a much simpler problem, which is how to handle array of contacts.
You just need know the following things:
Map function
How to update array without mutating the original array
I'll use TypeScript so you can understand better.
const [state, setState] = React.useState<{
contacts: {name: string}[]
}>({contacts: []})
return (
<div>
{state.contacts.map((contact, index) => {
return (
<div>
Name:
<input value={contact.name} onChange={event => {
setState({
...state,
contacts: state.contacts.map((contact$, index$) =>
index === index$
? {...contact$, name: event.target.value}
: {...contact$}
)
})
}}/>
</div>
)
}}
</div>
)
Also, this kind of problem is fairly common in React, so understand and memorize this pattern will help you a lot.

You can do something like this.
import React, { useState, useEffect } from "react";
import ReactDOM from "react-dom";
const App = () => {
const [company, setCompany] = useState({
name: "",
city: "",
contact: {
totalOfContact: 1,
contacts: [{id: 0, contactName: "", telephoneNumber: ""}]
}
});
console.log(company);
useEffect(() => {
console.log("teste");
}, []);
const handleChange = (item, e,index) => {
if (item === "contactName" || item === "telephoneNumber") {
const contactsNew = [...company.contact.contacts];
contactsNew[index] = { ...contactsNew[index], [item]: e.target.value };
setCompany({
...company,
contact: { ...company.contact, contacts: contactsNew }
});
// How can I set company.contact.contacts[<current_index>].contactName/telephoneNumber with the data typed?
} else {
setCompany({ ...company, [item]: e.target.value });
}
};
const handleClick = e => {
e.preventDefault();
if (e.target.value === "add") {
const contactNew = {...company.contact};
contactNew.totalOfContact = contactNew.totalOfContact + 1;
contactNew.contacts.push({id:contactNew.totalOfContact -1, contactName: "", telephoneNumber: ""});
setCompany({...company, contact: {...contactNew}});
// How can I set company.contact.totalOfContact to 2 and create one more set of inputs tags for a second contact?
} else {
alert("Push company to somewhere to persist");
console.log(`The data of the company is: ${company}`);
}
};
return (
<div>
<form>
<h3>General Section</h3>
Name:{" "}
<input
type="text"
onChange={(e) => handleChange("name", e)}
value={company.name}
/>
<br />
City:{" "}
<input
type="text"
onChange={(e) => handleChange("city", e)}
value={company.city}
/>
<br />
<hr />
<h3>Contacts Section:</h3>
{company.contact.contacts.map((eachContact, index) => {
return <React.Fragment>
Name:{" "}
<input
type="text"
onChange={(e) => handleChange("contactName",e, index)}
value={eachContact.name}
/>
Telephone Numer:{" "}
<input
type="text"
onChange={(e) => handleChange("telephoneNumber",e, index)}
value={eachContact.telephoneNumber}
/>
<br />
</React.Fragment>
})}
<br />
<button value="add" onClick={e => handleClick(e)}>
Add More Contact
</button>
<br />
<br />
<hr />
<button value="save" onClick={e => handleClick(e)}>
Save
</button>
</form>
</div>
);
};
const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);
Your state structure looks like an ideal candidate for useReducer hook. I would suggest you try that instead of useState. Your code should look muck readable that way, I suppose. https://reactjs.org/docs/hooks-reference.html#usereducer

display input fields in customized way

I have a dynamic form. My input fields belong to different groups. I want to figure out a way to display them group-wise.
My state through which form input fields are generated is:
random:
{
name: "emp1", group: "employee",
name: "emp2", group: "employee",
name: "emp3", group: "employee",
name: "man1", group: "manager",
name: "man2", group: "manager"
}
My dynamic form is as follows:
const Form = (props) => {
return (
<div>
{props.items.map(item => (
name={item.key_name}
value={item.key_value}
onChange={e => props.handleChange(e)}
/>
)
)}
<button onClick={() => props.handleSubmit()} >
Submit
</button>
</div>
)
}
export default Form
right now my fields are generated side by side in a horizontal line
But I want to display them group wise; so something like this:
Employee: (3 input fields)
Manager: (2 input fields)

You just need to split your items by their group, then render them. I would make the group a component so it handles rendering the label and also the inputs
const Form = props => {
const itemsByGroup = {};
props.items.forEach(item => {
if (!itemsByGroup[item.group]) {
itemsByGroup[item.group] = [];
}
itemsByGroup[item.group].push(item);
});
return (
<div>
{Object.keys(itemsByGroup).map(groupName => (
<FormGroup
label={groupName}
fields={itemsByGroup[groupName]}
handleChange={props.handleChange}
key={groupName}
/>
))}
<button onClick={() => props.handleSubmit()}>Submit</button>
</div>
);
};
const FormGroup = ({ label, fields, handleChange }) => (
<div>
<label>{label}:</label>
{fields.map(field => (
<input
name={field.key_name}
value={field.key_value}
onChange={e => handleChange(e)}
/>
))}
</div>
);
See a live example here to play with
Edit
if you have to put it in one component you can just do this
const Form = props => {
const itemsByGroup = {};
props.items.forEach(item => {
if (!itemsByGroup[item.group]) {
itemsByGroup[item.group] = [];
}
itemsByGroup[item.group].push(item);
});
return (
<div>
{Object.keys(itemsByGroup).map(groupName => (
<div>
<label>{label}:</label>
{fields.map(field => (
<input
name={field.key_name}
value={field.key_value}
onChange={e => handleChange(e)}
/>
))}
</div>
))}
<button onClick={() => props.handleSubmit()}>Submit</button>
</div>
);
};