TODOLIST Update in REACT - javascript

So I was trying to update the value I got by the Addlist and I tried this but this isn;t working. Also when I click on the '+' button without writing anything, an empty list is created. How should I stop it. I've attached a code below.
import React from "react";
import "./App.css";
import { useState } from "react";
import TodoList from "./components/TodoList";
function App() {
const [input, setInput] = useState("");
const [list, setList] = useState([]);
const updateList = (e) => {
setInput(e.target.value);
};
const AddList = () => {
console.log("value added")
setList((addValue) => {
return [...addValue, input];
});
setInput("");
};
const updateItems=(id)=>{
const newValue=[...list].map((newVal)=>{
if(input.id===id){
input.text='';
}
return newVal;
})
setList(newValue);
}
const deleteItems = (id) => {
console.log("deleted");
setList((addValue) => {
return addValue.filter((element, index) => {
return index !== id;
});
});
};
return (
<div className="todo-app">
<h1> Enter Anything</h1>
<input
type="text"
placeholder="Add anything"
value={input}
onChange={updateList}
/>
<button onClick={AddList}>+</button>
<ul>
{list.map((itemsvalue, id) => {
return (
<TodoList
itemsValue={itemsvalue}
key={id}
onSelect={deleteItems}
id={id}
onUpdate={updateItems}
/>
);
})}
</ul>
</div>
);
}
export default App;
Any kind of help would be appreciated. Also if I want to split this into multiple components is there a way to do.

When user clicks on the add button there is the check for empty String AddList method
for ex:- User updates second index value, second position value will get updated.
const [input, setInput] = useState('');
const [list, setList] = useState([]);
const [index, setIndex] = useState(null);
const updateList = (e) => {
setInput(e.target.value);
};
useEffect(() => {
setList(list);
console.log(list, '<>?');
}, [index]);
const AddList = () => {
if (input.trim() !== '') {
setList([...list, input]);
}
setInput('');
};
const updateValue = (index) => {
console.log(list[index]);
setIndex(index);
if (list[index].trim() !== '') {
setInput(list[index]);
}
};
const UpdateList = () => {
list[index] = input;
console.log(list, 'before <>?');
setIndex(null);
setInput('');
};
return (
<div>
<input type="text" placeholder="Add anything" value={input} onChange={updateList} />
<button disabled={!index && !list.length === 0} onClick={AddList}>
Add
</button>
<button disabled={input.trim() === ''} onClick={UpdateList}>
Update
</button>
{list.map((m, index) => (
<h1 style={{ border: '1px solid black' }} onClick={() => updateValue(index)}>
{m}
</h1>
))}
</div>
);

Related

Material UI Pagination

I don't understand why my page can't recognize other pages when I click (for example on page 2, the same page appears again and again)
This is in MealNew.js component:
import React, {useEffect, useState } from "react";
import './MealNew.css';
import Card from "../UI/Card";
import AppPagination from "./AppPagination";
const MealNew = () => {
const [data, setData] = useState([]);
const [showData, setShowData] = useState(false);
const [query,setQuery] = useState('');
const[page,setPage] = useState(9);
const[numberOfPages,setNumberOfPages]= useState(10);
const handleClick = () => {
setShowData(true);
const link = `https://api.spoonacular.com/recipes/complexSearch?query=${query}&apiKey=991fbfc719c743a5896bebbd98dfe996&page=${page}`;
fetch (link)
.then ((response)=> response.json())
.then ((data) => {
setData(data.results)
setNumberOfPages(data.total_pages)
const elementFood = data?.map((meal,key) => {
return (<div key={key}>
<h1>{meal.title}</h1>
<img src={meal.image}
alt='e-meal'/>
</div> )
})
const handleSubmit = (e) => {
e.preventDefault();
handleClick();
}
useEffect(()=> {
handleClick();
},[page])
return (
<Card className="meal">
<form onSubmit={handleSubmit}>
<input
className="search"
placeholder="Search..."
value={query}
onChange={(e)=>setQuery(e.target.value)}/>
<input type='submit' value='Search'/>
</form>
<li className="meal">
<div className = 'meal-text'>
<h5>{showData && elementFood}</h5>
<AppPagination
setPage={setPage}
pageNumber={numberOfPages}
/>
</div>
</li>
</Card>
) }
export default MealNew;
This is in AppPagination.js component:
import React from "react";
import { Pagination } from "#mui/material";
const AppPagination = ({setPage,pageNumber}) => {
const handleChange = (page)=> {
setPage(page)
window.scroll(0,0)
console.log (page)
}
return (
<div >
<div >
<Pagination
onChange={(e)=>handleChange(e.target.textContent)}
variant="outlined"
count={pageNumber}/>
</div>
</div>
)
}
export default AppPagination;
Thanks in advance, I would appreciate it a lot
The only error I am getting in Console is this:
Line 64:3: React Hook useEffect has a missing dependency: 'handleClick'. Either include it or remove the dependency array react-hooks/exhaustive-deps
You are not following the spoonacular api.
Your link looks like this:
https://api.spoonacular.com/recipes/complexSearch?query=${query}&apiKey=<API_KEY>&page=${page}
I checked the spoonacular Search Recipes Api and there's no page parameter you can pass. You have to used number instead of page.
When you receive response from the api, it returns the following keys: offset, number, results and totalResults.
You are storing totalResults as totalNumberOfPages in state which is wrong. MUI Pagination count takes total number of pages not the total number of records. You can calculate the total number of pages by:
Math.ceil(totalRecords / recordsPerPage). Let say you want to display 10 records per page and you have total 105 records.
Total No. of Pages = Math.ceil(105/10)= 11
Also i pass page as prop to AppPagination component to make it as controlled component.
Follow the documentation:
Search Recipes
Pagination API
Complete Code
import { useEffect, useState } from "react";
import { Card, Pagination } from "#mui/material";
const RECORDS_PER_PAGE = 10;
const MealNew = () => {
const [data, setData] = useState([]);
const [showData, setShowData] = useState(false);
const [query, setQuery] = useState("");
const [page, setPage] = useState(1);
const [numberOfPages, setNumberOfPages] = useState();
const handleClick = () => {
setShowData(true);
const link = `https://api.spoonacular.com/recipes/complexSearch?query=${query}&apiKey=<API_KEY>&number=${page}`;
fetch(link)
.then((response) => response.json())
.then((data) => {
setData(data.results);
const totalPages = Math.ceil(data.totalResults / RECORDS_PER_PAGE);
setNumberOfPages(totalPages);
});
};
const elementFood = data?.map((meal, key) => {
return (
<div key={key}>
<h1>{meal.title}</h1>
<img src={meal.image} alt='e-meal' />
</div>
);
});
const handleSubmit = (e) => {
e.preventDefault();
handleClick();
};
useEffect(() => {
handleClick();
console.log("first");
}, [page]);
return (
<Card className='meal'>
<form onSubmit={handleSubmit}>
<input className='search' placeholder='Search...' value={query} onChange={(e) => setQuery(e.target.value)} />
<input type='submit' value='Search' />
</form>
<li className='meal'>
<div className='meal-text'>
<h5>{showData && elementFood}</h5>
<AppPagination setPage={setPage} pageNumber={numberOfPages} page={page} />
</div>
</li>
</Card>
);
};
const AppPagination = ({ setPage, pageNumber, page }) => {
const handleChange = (page) => {
setPage(page);
window.scroll(0, 0);
console.log(page);
};
console.log("numberOfPages", pageNumber);
return (
<div>
<div>
<Pagination
page={page}
onChange={(e) => handleChange(e.target.textContent)}
variant='outlined'
count={pageNumber}
/>
</div>
</div>
);
};
export default MealNew;

How to get each user's keystroke when he pressed a certain key?

I need to get each user's keystroke when he pressed a certain key("#") and stop getting his keystroke when he pressed other key(space(" ")). For example: a user enters the text "I wanna go to #shop", I need to save his input and the tag inside it. How can I do it? I wrote some code to do it but I don't know how to make it completely
onKeyDown = (e) => {
let value = e.target.value, tags = [], currentTag = "";
if (e.key == "Enter") {
this.setState((state) => {
const item = this.createNote(value, tags);
return { notes: [...state.notes, item] };
});
}
if (e.key == "#") {}
};
You can make use of regex /#[^\s]+/g
Live Demo
export default function App() {
const [value, setValue] = useState("");
const [tags, setTags] = useState([]);
function onInputChange(e) {
const value = e.target.value;
setValue(value);
const tags = value.match(/#[^\s]+/g) ?? [];
setTags(tags);
}
return (
<>
<input type="text" name="" value={value} onChange={onInputChange} />
<ul>
{tags.map((tag) => {
return <li key={tag}> {tag} </li>;
})}
</ul>
</>
);
}
EDITED: You can make use of useMemo hook as
Thanks to 3limin4t0r
Live Demo
export default function App() {
const [value, setValue] = useState("");
const tags = useMemo(() => value.match(/#\S+/g) || [], [value]);
function onInputChange(e) {
const value = e.target.value;
setValue(value);
}
return (
<>
<input type="text" name="" value={value} onChange={onInputChange} />
<ul>
{tags.map((tag) => {
return <li key={tag}> {tag} </li>;
})}
</ul>
</>
);
}
Instead of parsing individual key values, you can use a function like this to parse your input field on changes and return an array of hashtags (without the leading #):
TS Playground link
function parseTags (input: string): string[] {
return (input.match(/(?:^#|[\s]#)[^\s]+/gu) ?? []).map(s => s.trim().slice(1));
}
Here's a working example in a functional component which incorporates the function:
<script src="https://unpkg.com/react#17.0.2/umd/react.development.js"></script>
<script src="https://unpkg.com/react-dom#17.0.2/umd/react-dom.development.js"></script>
<script src="https://unpkg.com/#babel/standalone#7.16.4/babel.min.js"></script>
<div id="root"></div>
<script type="text/babel" data-type="module" data-presets="react">
const {useState} = React;
function parseTags (input) {
return (input.match(/(?:^#|[\s]#)[^\s]+/gu) ?? []).map(s => s.trim().slice(1));
}
function Example () {
const [value, setValue] = useState('');
const [tags, setTags] = useState([]);
const handleChange = (ev) => {
const {value} = ev.target;
setValue(value);
setTags(parseTags(value));
};
return (
<div>
<input
type="text"
onChange={handleChange}
placeholder="Type here"
value={value}
/>
<div>Parsed tags:</div>
<ol>
{tags.map((str, index) => <li key={`${index}.${str}`}>{str}</li>)}
</ol>
</div>
);
}
ReactDOM.render(<Example />, document.getElementById('root'));
</script>
Something like this should work for you; You can adapt if you don't have access to hooks:
const RecorderInput = ({ onChange }) => {
const [isRecording, setIsRecording] = useState(false);
const toggleRecording = (e) => {
const character = String.fromCharCode(e.charCode);
if (character === '#') {
setIsRecording(true);
}
if (character === ' ') {
setIsRecording(false);
}
}
const handleChange = (e) => {
if (isRecording) onChange(e);
toggleRecording(e);
}
<input type="text" onChange={handleChange} />
}
As other suggested your onChange can also use regex groups to capture hashes as the user types. Thinking about this now, it would probably be a lot cleaner to do it this way but regex is well documented so I won't go through the hassle

React useState being ignored

I have a small React app where you can click on a piece of text to replace it with an input field, to allow you to edit it.
The problem is that the EditableText component does not seem to want to display the editingText state in the input field.
See example here: https://codesandbox.io/s/distracted-ellis-kyrdb
For posterity, the code for the main app is:
export default function App() {
const [cats, setCats] = useState([
{
id: 1,
name: "fred"
},
{
id: 2,
name: "jim"
}
]);
const [activeCat, setActiveCat] = useState({});
const handleClick = (cat, e) => {
setActiveCat(cat);
};
const saveName = (newName) => {
// save this cat's new name...
};
return (
<div className="App">
<div className="catMenu">
{cats.map((row) => (
<div
className="catItem"
key={row.id}
onClick={(e) => handleClick(row, e)}
>
{row.name}
</div>
))}
</div>
<div className="activeCat">
<h2>
<EditableText text={activeCat.name} saveText={saveName} />
</h2>
</div>
</div>
);
}
and for the EditableText component:
const EditableText = (props) => {
const { text, saveText } = props;
const [editing, setEditing] = useState(false);
const [editingText, setEditingText] = useState(text);
useEffect(() => {
const handleKeydown = (e) => {
if (editing) {
if (e.keyCode === 13) {
// Enter key pressed
saveText(editingText);
setEditing(false);
}
if (e.keyCode === 27) {
// Escape key pressed
setEditingText(text);
setEditing(false);
}
}
};
window.addEventListener("keydown", handleKeydown);
return () => {
window.removeEventListener("keydown", handleKeydown);
};
}, [text, saveText, editing, editingText]);
return (
<div>
<div
onClick={() => setEditing(true)}
className={`et-${editing ? "hidden" : "active"}`}
>
{text}
</div>
<input
type="text"
value={editingText}
onChange={(e) => setEditingText(e.target.value)}
className={`et-input-${editing ? "active" : "hidden"}`}
/>
</div>
);
};
export default EditableText;
Add another useEffect to listen to text prop change, you only use it as initial empty value:
useEffect(() => {
setEditingText(text);
}, [text]);

Button handler to show preview

Iam doing one of the react assignment and I am stuck on the last part of this assignment. The question is like this: Improve on the application in the previous exercise, such that when the names of multiple countries are shown on the page there is a button next to the name of the country, which when pressed shows the view for that country. Here is my code. I tried some functions but couldnot get it so I wonder if someone can help me to cope with this last part..Thank you
import React, { useState, useEffect } from "react";
import axios from "axios";
import ReactDOM from "react-dom";
const App = () => {
const [countries, setCountries] = useState([]);
const [filter, setFilter] = useState("");
const [select, setSelected] = useState([]);
//console.log(countries);
useEffect(() => {
axios.get("https://restcountries.eu/rest/v2/all").then((response) => {
setCountries(response.data);
});
}, []);
const searchHandler = (e) => {
setFilter(e.target.value);
//console.log(filter);
const selected_countries = countries.filter((item) => {
const letter_case=item.name.toLowerCase().includes(filter.toLowerCase())
return letter_case
});
setSelected(selected_countries);
};
const countryLanguages = (languages)=>
languages.map(language => <li key={language.name}>{language.name}</li>)
const showCountries = () => {
if (select.length === 0) {
return <div></div>
} else if (select.length > 10) {
return "Find the specific filter";
}
else if(select.length>1 && select.length<10){
return (select.map(country=>
<div key={country.alpha3code}>{country.name}
<button>Show</button>//this part
</div>)
)
}
else if(select.length===1){
return(
<div>
<h1>{select[0].name}</h1>
<div>capital {select[0].capital}</div>
<div>population {select[0].population}</div>
<h2>languages</h2>
<ul>{countryLanguages(select[0].languages)}</ul>
<img src={select[0].flag} width="100px"/>
<h2>Weather in {select[0].capital}</h2>
</div>
)
}
};
return (
<div>
<h1>Countries</h1>
find countries: <input value={filter} onChange={searchHandler} />
{showCountries()}
</div>
);
};
ReactDOM.render(<App />, document.getElementById("root"));
Create a separate component.
const SingleCountry = ({name}) => {
const [ showDetails, setShowDetails ] = useState(false);
const toggleDetails = () => setShowDetails(!showDetails); //toggles the variable true/false
return ( <div>
<button onClick={toggleDetails}>Show Details</button>
{ /* renders the <div> only if showDetails is true */ }
{ showDetails && <div>These are the details of the country {name}</div> }
</div>)
}
Edit your showCountries component to use the new component.
const showCountries = () => {
if (select.length === 0) {
return <div></div>
} else if (select.length > 10) {
return "Find the specific filter";
}
else if(select.length>1 && select.length<10){
return (select.map(country=> <SingleCountry key={country.alpha3code} name={country.name} />
)
}

How to add a whole array to useState variable

I'm trying to add a whole array to useState variable
import React, { Fragment, useState, useEffect } from 'react';
import { Form, Button, Popover, OverlayTrigger } from 'react-bootstrap';
const Filter = props => {
const [formData, setFormData] = useState({
filter: ''
});
const [items, setItems] = useState([]);
const [retrievedItems, setRetrievedItems] = useState([]);
const addToFilter = newFilter => {
let retrievedFilter = ["da vinci","paris", "london"];
console.log(retrievedFilter);
if (retrievedFilter.length > 0) {
setRetrievedItems([...retrievedItems, retrievedFilter]);
retrievedFilter = 0;
setRetrievedItems([...retrievedItems, newFilter]);
} else {
setItems([...items, newFilter]);
}
console.log('items are: ', items);
console.log('retrieve filter', props.retrievedFilter);
console.log('retrieved items: ', retrievedItems);
};
useEffect(() => {
console.log('useEffect ', retrievedItems);
}, [retrievedItems]);
const deleteFilter = index => {
// props.retrievedFilter.splice(index, 1);
items.splice(index, 1);
setItems([...items]);
// setItems([...props.retrievedFilter, ...items]);
console.log(items);
};
const { filter } = formData;
const onChange = e => {
setFormData({ ...formData, [e.target.name]: e.target.value });
};
const onSubmit = e => {
e.preventDefault();
addToFilter(filter);
// Passing filter data up (i.e: to components that use <Filter />)
props.filterData(filter);
//Close the Popover
document.body.click();
};
const popover = (
<Popover id="popover-basic">
<Form>
<Form.Group controlId="formGroupEmail">
<Form.Label>Add New Filter</Form.Label>
<Form.Control
type="text"
placeholder="New Filter"
name="filter"
onChange={e => onChange(e)}
/>
</Form.Group>
<Button variant="dark" type="submit" onClick={e => onSubmit(e)}>
Add
</Button>
</Form>
</Popover>
);
return (
<Fragment>
<label>
<p className="filter-title">{props.title}</p>
</label>
<div className={props.className ? props.className : 'filter'}>
{!props.retrievedFilter
? items.map((item, index) => {
return (
<div className="filter-text" key={index}>
{item}
<Button
className="filter-button"
size="sm"
onClick={() => deleteFilter(index)}
>
X
</Button>
</div>
);
})
: props.retrievedFilter.map((item, index) => {
return (
<div className="filter-text" key={index}>
{item}
<Button
className="filter-button"
size="sm"
onClick={() => deleteFilter(index)}
>
X
</Button>
</div>
);
})}
<OverlayTrigger
trigger="click"
placement="right"
rootClose
overlay={popover}
>
<p className="text-field">Type new one</p>
</OverlayTrigger>
</div>
</Fragment>
);
};
export default Filter;
however retrievedItems shows as an empty array in the console.
any help would be appreciated.
setState is async. You have to console.log inside an effect hook with the array as a parameter.
useEffect(() => console.log(retrieved_items), [ retrievedItems ])
The second parameter ensures that the effect fires in repose to a change in the values passed to it.
Per my comment, here is a code snippet that I think does what you want.
I couldn't get it running in SO but here's a codepen: https://codepen.io/anon/pen/PrYYmz?editors=1010 (watch the chrome console as you add items)
import React, {
Fragment,
useState,
useEffect
} from 'react';
const Filter = props => {
const [formData, setFormData] = useState({filter: ''});
const [items, setItems] = useState([]);
const [retrievedItems, setRetrievedItems] = useState([]);
const addToFilter = newFilter => {
let retrievedFilter = ["da vinci", "paris", "london"];
console.log('add', retrievedFilter);
if (retrievedFilter.length > 0) {
setRetrievedItems([...retrievedItems, retrievedFilter]);
retrievedFilter = 0;
setRetrievedItems([...retrievedItems, newFilter]);
} else {
setItems([...items, newFilter]);
}
console.log('items are: ', items);
console.log('retrieve filter', props.retrievedFilter);
console.log('retrieved items: ', retrievedItems);
};
useEffect(() => {
console.log('useEffect ', retrievedItems);
}, [retrievedItems]);
const deleteFilter = index => {
// props.retrievedFilter.splice(index, 1);
items.splice(index, 1);
setItems([...items]);
// setItems([...props.retrievedFilter, ...items]);
console.log(items);
};
const {filter} = formData;
const onChange = e => {
setFormData({ ...formData,
[e.target.name]: e.target.value
});
};
const onSubmit = e => {
e.preventDefault();
addToFilter(filter);
// Passing filter data up (i.e: to components that use <Filter />)
//props.filterData(filter);
//Close the Popover
document.body.click();
};
return (
<Fragment >
<label >
<p className = "filter-title" > {
props.title
} </p> </label> <
div className = {
props.className ? props.className : 'filter'
} > {!props.retrievedFilter ?
items.map((item, index) => {
return ( <
div className = "filter-text"
key = {index} > {item} <button className = "filter-button" size = "sm" onClick = {() => deleteFilter(index)}>X</button></div>
);
}) :
props.retrievedFilter.map((item, index) => {
return ( <div className = "filter-text" key = {index} > {item} <button className = "filter-button" size = "sm" onClick = {() => deleteFilter(index)} >X</button></div>);})} <input type = "text" placeholder = "New Filter" name = "filter" onChange = {e => onChange(e) }/>
<button variant = "dark" type = "submit" onClick = {e => onSubmit(e)} >Add</button>
</div>
</Fragment>
);
};
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.8.6/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.6/umd/react-dom.production.min.js"></script>

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