How to avoid prop drilling ? / How to use useContext? - javascript

I'm working on a React Notes Application and my App.js contains all the necessary functions props which are passed down to several components.
As a result I'm doing prop drilling a lot where I'm passing down around 10-20 props/functions in the components where it isn't needed.
I tried using useContext Hook but I guess it doesn't work with callback functions in the value parameter.
App.js
const App = () => {
const [ notes, setNotes ] = useState([]);
const [ category, setCategory ] = useState(['Notes']);
const [ searchText, setSearchText ] = useState('');
const [ alert, setAlert ] = useState({
show:false,
msg:'',
type:''
});
const [isEditing, setIsEditing] = useState(false);
const [editId, setEditId] = useState(null);
useEffect(()=>{
keepTheme();
})
// retreive saved notes
useEffect(()=>{
const savedNotes = JSON.parse(localStorage.getItem('react-notes-data'));
if (savedNotes) {
setNotes(savedNotes)
}
}, []);
// save notes to local storage
useEffect(() => {
localStorage.setItem('react-notes-data', JSON.stringify(notes))
setNotesCopy([...notes]);
}, [notes]);
// save button will add new note
const addNote = (text) => {
const date = new Date();
const newNote = {
id: nanoid(),
text: text,
date: date.toLocaleDateString(),
category: category,
}
const newNotes = [...notes, newNote]
setNotes(newNotes);
}
const deleteNote = (id) => {
showAlert(true, 'Note deleted', 'warning');
const newNotes = notes.filter(note => note.id !== id);
setNotes(newNotes);
}
// hardcoded values for categories
const allCategories = ['Notes', 'Misc', 'Todo', 'Lecture Notes', 'Recipe'];
// copy notes for filtering through
const [notesCopy, setNotesCopy] = useState([...notes]);
const handleSidebar = (category) => {
setNotesCopy(category==='Notes'?[...notes]:
notes.filter(note=>note.category===category));
}
// function to call alert
const showAlert = (show=false, msg='', type='') => {
setAlert({show, msg, type});
}
return (
<div>
<div className="container">
<Sidebar
allCategories={allCategories}
handleSidebar={handleSidebar}
notesCopy={notesCopy}
key={notes.id}
/>
<Header notes={notes} alert={alert} removeAlert={showAlert} />
<Search handleSearchNote={setSearchText} />
<NotesList
notesCopy={notesCopy.filter(note=>
note.text.toLowerCase().includes(searchText) ||
note.category.toString().toLowerCase().includes(searchText)
)}
handleAddNote={addNote}
deleteNote={deleteNote}
category={category}
setCategory={setCategory}
allCategories={allCategories}
showAlert={showAlert}
notes={notes}
setNotes={setNotes}
editId={editId}
setEditId={setEditId}
isEditing={isEditing}
setIsEditing={setIsEditing}
/>
</div>
</div>
)
}
NotesList.js
const NotesList = (
{ notesCopy, handleAddNote, deleteNote, category, setCategory, showHideClassName, allCategories, showAlert, isEditing, setIsEditing, notes, setNotes, editId, setEditId }
) => {
const [ noteText, setNoteText ] = useState('');
const textareaRef = useRef();
// function to set edit notes
const editItem = (id) => {
const specificItem = notes.find(note=>note.id === id);
setNoteText(specificItem.text);
setIsEditing(true);
setEditId(id);
textareaRef.current.focus();
}
return (
<div key={allCategories} className="notes-list">
{notesCopy.map(note => {
return (
<Note
key={note.id}
{...note}
deleteNote={deleteNote}
category={note.category}
isEditing={isEditing}
editId={editId}
editItem={editItem}
/>)
})}
<AddNote
handleAddNote={handleAddNote}
category={category}
setCategory={setCategory}
showHideClassName={showHideClassName}
allCategories={allCategories}
showAlert={showAlert}
isEditing={isEditing}
setIsEditing={setIsEditing}
notes={notes}
setNotes={setNotes}
editId={editId}
setEditId={setEditId}
noteText={noteText}
setNoteText={setNoteText}
textareaRef={textareaRef}
/>
</div>
)
}
AddNote.js
const AddNote = ({ notes, setNotes, handleAddNote, category, setCategory, showHideClassName, allCategories, showAlert, isEditing, setIsEditing, editId, setEditId, noteText, setNoteText, textareaRef }) => {
const [ show, setShow ] = useState(false);
const [ modalText, setModalText ] = useState('');
const charCount = 200;
const handleChange = (event) => {
if (charCount - event.target.value.length >= 0) {
setNoteText(event.target.value);
}
}
const handleSaveClick = () => {
if (noteText.trim().length === 0) {
setModalText('Text cannot be blank!');
setShow(true);
}
if (category === '') {
setModalText('Please select a label');
setShow(true);
}
if (noteText.trim().length > 0 && category!=='') {
showAlert(true, 'Note added', 'success');
handleAddNote(noteText);
setNoteText('');
setShow(false);
}
if (noteText.trim().length > 0 && category!=='' && isEditing) {
setNotes(notes.map(note=>{
if (note.id === editId) {
return ({...note, text:noteText, category:category})
}
return note
}));
setEditId(null);
setIsEditing(false);
showAlert(true, 'Note Changed', 'success');
}
}
const handleCategory = ( event ) => {
let { value } = event.target;
setCategory(value);
}
showHideClassName = show ? "modal display-block" : "modal display-none";
return (
<div className="note new">
<textarea
cols="10"
rows="8"
className='placeholder-dark'
placeholder="Type to add a note.."
onChange={handleChange}
value={noteText}
autoFocus
ref={textareaRef}
>
</textarea>
<div className="note-footer">
<small
className='remaining'
style={{color:(charCount - noteText.length == 0) && '#c60000'}}>
{charCount - noteText.length} remaining</small>
<div className='select'>
<select
name={category}
className="select"
onChange={(e)=>handleCategory(e)}
required
title='Select a label for your note'
defaultValue="Notes"
>
<option value="Notes" disabled selected>Categories</option>
{allCategories.map(item => {
return <option key={item} value={item}>{item}</option>
})}
</select>
</div>
<button className='save' onClick={handleSaveClick} title='Save note'>
<h4>{isEditing ? 'Edit':'Save'}</h4>
</button>
</div>
{/* Modal */}
<main>
<div className={showHideClassName}>
<section className="modal-main">
<p className='modal-text'>{modalText}</p>
<button type="button" className='modal-close-btn'
onClick={()=>setShow(false)}><p>Close</p>
</button>
</section>
</div>
</main>
</div>
)
}
I want the functions passed from App.js to NotesList.js to be in AddNote.js without them being passed in NotesList.js basically minimizing the props destructuring in NotesList.js

Context API does work with function. What you need to do is pass your function to Provider inside value :
<MyContext.Provider value={{notes: notesData, handler: myFunction}} >
For example:
// notes-context.js
import React, { useContext, createContext } from 'react';
const Context = createContext({});
export const NotesProvider = ({children}) => {
const [notes, setNote] = useState([]);
const addNote = setNote(...); // your logic
const removeNote = setNote(...); // your logic
return (
<Context.Provider value={{notes, addNote, removeNote}}>
{children}
</Context.Provider>
)
}
export const useNotes = () => useContext(Context);
Add Provider to your App.js like so:
// App.js
import NoteProvider from './notes-context';
export default App = () => {
return (
<NoteProvider>
<div>... Your App</div>
</NoteProvider>
)
}
Then call UseNote in your NoteList.js to use the function:
// NoteList.js
import {useNotes} from './note-context.js';
export const NoteList = () => {
const {notes, addNotes, removeNotes} = useNotes();
// do your stuff. You can now use functions addNotes and removeNotes without passing them down the props
}

Related

Filtering a todo list based on button clicked on React

I'm currently working on a to-do list app. Currently, I'm able to add, delete and edit the to-do list. I have a problem filtering my to-do list based on categories. The categories I have are all, active and completed. I'm stuck trying to filter the selected list based on the button clicked.
App.jsx:
import './App.css'
import Todo from './components/Todo';
import FilterButton from './components/FilterButton';
import Form from './components/form';
import { nanoid } from "nanoid";
function usePrevious(value) {
const ref = useRef();
useEffect(() => {
ref.current = value;
});
return ref.current;
}
const filterMap = {
All: () => true,
Active: (task) => !task.completed,
Completed: (task) => task.completed
};
const filterNames = Object.keys(filterMap);
function App(props) {
const [tasks, setTasks] = useState(props.tasks);
const [filter, setFilter] = useState('ALL');
function toggleTaskCompleted(id) {
const updatedTasks = tasks.map((task) => {
// if this task has the same ID as the edited task
if (id === task.id) {
// use object spread to make a new object
// whose `completed` prop has been inverted
return {...task, completed: !task.completed}
}
return task;
});
setTasks(updatedTasks);
}
function deleteTask(id) {
const remainingTasks = tasks.filter((task) => id !== task.id);
setTasks(remainingTasks);
}
function editTask(id, newName) {
const editedTaskList = tasks.map((task) => {
// if this task has the same ID as the edited task
if (id === task.id) {
return {...task, name: newName}
}
return task;
});
setTasks(editedTaskList);
}
const taskList =tasks
.filter((filterNames[filter]))
.map((task)=> (
<Todo
id={task.id}
name={task.name}
completed={task.completed}
key={task.id}
toggleTaskCompleted={toggleTaskCompleted}
deleteTask={deleteTask}
editTask={editTask}
/>
));
const filterList = filterNames.map((name) => (
<FilterButton
key={name}
name={name}
isPressed={name === filter}
setFilter={setFilter}
/>
));
function addTask(name) {
const newTask = { id: `todo-${nanoid()}`, name, completed: true };
setTasks([...tasks, newTask]);
}
const tasksNoun = taskList.length !== 1 ? 'tasks' : 'task';
const headingText = `${taskList.length} ${tasksNoun} remaining`;
const listHeadingRef = useRef(null);
const prevTaskLength = usePrevious(tasks.length);
useEffect(() => {
if (tasks.length - prevTaskLength === -1) {
listHeadingRef.current.focus();
}
}, [tasks.length, prevTaskLength]);
return (
<div className="todoapp stack-large">
<h1>TodoApp</h1>
<Form addTask={addTask} />
<div className="filters btn-group stack-exception">
{filterList}
</div>
<h2 id="list-heading" tabIndex="-1" ref={listHeadingRef}>
{headingText}
</h2>
<ul
role="list"
className="todo-list stack-large stack-exception"
aria-labelledby="list-heading"
>
{taskList}
</ul>
</div>
);
}
export default App;
FilterButton
''import React from "react";
function FilterButton(props) {
return (
<button
type="button"
className="btn toggle-btn"
aria-pressed={props.isPressed}
onClick={() => props.setFilter(props.name)}
>
<span className="visually-hidden">Show </span>
<span>{props.name}</span>
<span className="visually-hidden"> tasks</span>
</button>
);
}
export default FilterButton; ```
You're passing filterName that actually only contains the keys, not the method. Also, make sure you're getting tasks as an array from props.
Update your state as well to
const [tasks, setTasks] = useState(props.tasks || [] );
const taskList = useMemo(()=>tasks
.filter(filterMap[filter])
.map((task)=> (
<Todo
.....
/>
)),[tasks,filter]);
Also just wrap your taskList with useMemo so whenever tasks & filter change your taskList will be updated.

useState defaults appear to rerun after running function on state change, defaults shouldnt run twice

I have the following issue with website where the settings state resets after running more searches. The settings component is show below in the picture, it usually works but if you uncheck a box and then run a few more searches at some point the showAllDividends setting will be set to false, the All dividends component won't be on the screen, but for some reason the checkbox itself is checked (true). This is my first time really working with checkboxes in React, and I think I'm using the onChange feature wrong. Right now I get the event.target.checked boolean, but only onChange.
If that isn't the issue then the most likely cause is the default statements being run again on another render:
const [showMainInfo, setShowMainInfo] = useState(true);
const [showYieldChange, setShowYieldChange] = useState(true);
const [showAllDividends, setShowAllDividends] = useState(true);
the thing is I don't see why the default statements would run more than once, the component isn't being destroyed there's no react router usage. I expected it to keep its current state after the page is first loaded. I think the settings defaults are being rerun, but just don't understand why they would.
I unchecked, checked, unchecked the 'All dividends' checkbox, and it was unchecked when I ran 2 more searches. After the second search the checkbox was checked but the component was gone, because showAllDividends was false
main component SearchPage.js:
import React, {useState, useEffect} from 'react';
import { connect } from 'react-redux';
import axios from 'axios';
import SearchBar from './SearchBar';
import AllDividendsDisplay from './dividend_results_display/AllDividendsDisplay';
import DividendResultsDisplay from './dividend_results_display/DividendResultsDisplay';
import SettingsView from './settings/SettingsView';
const HOST = process.env.REACT_APP_HOSTNAME
const PROTOCOL = process.env.REACT_APP_PROTOCOL
const PORT = process.env.REACT_APP_PORT
const BASE_URL = PROTOCOL + '://' + HOST + ':' + PORT
const SearchPage = ({userId}) => {
const DEFAULT_STOCK = 'ibm';
const [term, setTerm] = useState(DEFAULT_STOCK);
const [debouncedTerm, setDebouncedTerm] = useState(DEFAULT_STOCK);
const [loading, setLoading] = useState(false);
const [recentSearches, setRecentSearches] = useState([DEFAULT_STOCK]);
const [dividendsYearsBack, setDividendsYearsBack] = useState('3');
const [debouncedDividendYearsBack, setDebouncedDividendYearsBack] = useState('3');
const [errorMessage, setErrorMessage] = useState('');
const [dividendsData, setDividendsData] = useState(
{
current_price: '',
recent_dividend_rate: '',
current_yield: '',
dividend_change_1_year: '',
dividend_change_3_year: '',
dividend_change_5_year: '',
dividend_change_10_year: '',
all_dividends: [],
name: '',
description: '',
}
)
const [settingsViewVisible, setSettingsViewVisible] = useState(false);
const [showMainInfo, setShowMainInfo] = useState(true);
const [showYieldChange, setShowYieldChange] = useState(true);
const [showAllDividends, setShowAllDividends] = useState(true);
const onTermUpdate = (term) => {
setTerm(term)
}
// TODO: write a custom hook that debounces taking the term and the set debounced term callback
useEffect(() => {
const timerId = setTimeout(() => {
setDebouncedTerm(term);
}, 1500);
return () => {
clearTimeout(timerId);
};
}, [term]);
useEffect(() => {
const timerId = setTimeout(() => {
setDebouncedDividendYearsBack(dividendsYearsBack);
}, 1500);
return () => {
clearTimeout(timerId);
};
}, [dividendsYearsBack]);
useEffect(() => {runSearch()}, [debouncedTerm]);
useEffect(() => {
// alert(dividendsYearsBack)
if (dividendsYearsBack !== '') {
runSearch();
}
}, [debouncedDividendYearsBack])
useEffect(() => {
console.log("user id changed")
if (userId) {
const user_profile_api_url = BASE_URL + '/users/' + userId
axios.get(user_profile_api_url, {})
.then(response => {
const recent_searches_response = response.data.searches;
const new_recent_searches = [];
recent_searches_response.map(dict => {
new_recent_searches.push(dict.search_term)
})
setRecentSearches(new_recent_searches);
})
.catch((error) => {
console.log("error in getting user profile: ", error.message)
})
}
}, [userId])
useEffect(() => {
const user_profile_api_url = BASE_URL + '/users/' + userId
const request_data = {searches: recentSearches}
axios.post(user_profile_api_url, request_data)
// .then(response => {
// console.log(response)
// })
}, [recentSearches])
const makeSearchApiRequest = () => {
let dividends_api_url = BASE_URL + '/dividends/' + term + '/' + dividendsYearsBack
if (!recentSearches.includes(term)) {
setRecentSearches([...recentSearches, term])
}
axios.get(dividends_api_url, {})
.then(response => {
// console.log(response)
setLoading(false);
setDividendsData(response.data);
})
.catch((error) => {
console.log(error.message);
setLoading(false);
setErrorMessage(error.message);
})
}
const runSearch = () => {
console.log("running search: ", term);
setErrorMessage('');
if (term) {
setLoading(true);
if (!dividendsYearsBack) {
setDividendsYearsBack('3', () => {
makeSearchApiRequest()
});
} else {
makeSearchApiRequest()
}
}
}
const recentSearchOnClick = (term) => {
setTerm(term);
setDebouncedTerm(term);
}
const removeRecentSearchOnClick = (term) => {
const searchesWithoutThisOne = recentSearches.filter(search => search !== term)
setRecentSearches(searchesWithoutThisOne);
}
const dividendsYearsBackOnChange = (text) => {
setDividendsYearsBack(text);
}
const renderMainContent = () => {
if (!debouncedTerm) {
return (
<div className="ui active">
<div className="ui text">Search for info about a stock</div>
</div>
)
}
if (loading === true) {
return (
<div className="ui active dimmer">
<div className="ui big text loader">Loading</div>
</div>
)
}
if (errorMessage) {
return (
<div className="ui active">
<div className="ui text">{errorMessage}</div>
</div>
)
} else {
return (
<DividendResultsDisplay
data={dividendsData}
dividends_years_back={dividendsYearsBack}
dividendsYearsBackOnChange={dividendsYearsBackOnChange}
showMainInfo={showMainInfo}
showYieldChange={showYieldChange}
showAllDividends={showAllDividends}/>
)
}
}
// https://stackoverflow.com/questions/38619981/how-can-i-prevent-event-bubbling-in-nested-react-components-on-click
const renderRecentSearches = () => {
return recentSearches.map((term) => {
return (
<div key={term}>
<button
onClick={() => recentSearchOnClick(term)}
style={{marginRight: '10px'}}
>
<div>{term} </div>
</button>
<button
onClick={(event) => {event.stopPropagation(); removeRecentSearchOnClick(term)}}>
X
</button>
<br/><br/>
</div>
)
})
}
const renderSettingsView = (data) => {
if (settingsViewVisible) {
return (
<SettingsView data={data} />
)
} else {
return null;
}
}
const toggleSettingsView = () => {
setSettingsViewVisible(!settingsViewVisible);
}
const toggleDisplay = (e, setter) => {
setter(e.target.checked)
}
const SETTINGS_DATA = [
{
label: 'Main info',
id: 'main_info',
toggler: toggleDisplay,
setter: setShowMainInfo
},
{
label: 'Yield change',
id: 'yield_change',
toggler: toggleDisplay,
setter: setShowYieldChange
},
{
label: 'Dividends list',
id: 'all_dividends',
toggler: toggleDisplay,
setter: setShowAllDividends
},
]
console.log("showMainInfo: ", showMainInfo);
console.log("showYieldChange: ", showYieldChange);
console.log("showAllDividends: ", showAllDividends);
return (
<div className="ui container" style={{marginTop: '10px'}}>
<SearchBar term={term} onTermUpdate={onTermUpdate} />
{renderRecentSearches()}
<br/><br/>
<button onClick={toggleSettingsView}>Display settings</button>
{renderSettingsView(SETTINGS_DATA)}
<div className="ui segment">
{renderMainContent()}
</div>
</div>
)
}
const mapStateToProps = state => {
return { userId: state.auth.userId };
};
export default connect(
mapStateToProps
)(SearchPage);
// export default SearchPage;
the settingsView component:
import React from 'react';
import SettingsCheckbox from './SettingsCheckbox';
const SettingsView = ({data}) => {
const checkboxes = data.map((checkbox_info) => {
return (
<div key={checkbox_info.id}>
<SettingsCheckbox
id={checkbox_info.id}
label={checkbox_info.label}
toggler={checkbox_info.toggler}
setter={checkbox_info.setter}/>
<br/>
</div>
)
});
return (
<div className="ui segment">
{checkboxes}
</div>
);
}
export default SettingsView;
SettingsCheckbox.js:
import React, {useState} from 'react';
const SettingsCheckbox = ({id, label, toggler, setter}) => {
const [checked, setChecked] = useState(true)
return (
<div style={{width: '200px'}}>
<input
type="checkbox"
checked={checked}
id={id}
name={id}
value={id}
onChange={(e) => {
setChecked(!checked);
toggler(e, setter);
}} />
<label htmlFor="main_info">{label}</label><br/>
</div>
);
}
export default SettingsCheckbox;

How can I get my Note element to update when I change its text?

sorry for the long post, but I'm really stuck in this part of my project. I'm using React to build a notes app, and I can't get my note to update when I alter the text inside of my modal popup...the commented out parts are where I'm having trouble (I wrote what I thought of doing, but don't know how. I've been using React for less than a week). Thank you in advance!
App.js
import React, { useState } from "react";
import { nanoid } from "nanoid";
import NotesList from "./Components/NotesList";
import AddNote from "./Components/AddNote";
const App = () => {
const [notes, setNotes] = useState([
/*empty array of notes*/
]);
const addNote = (title, text) => {
const date = new Date();
const newNote = {
id: nanoid(),
title: title,
text: text,
date: date.toDateString(),
};
const newNotes = [...notes, newNote];
setNotes(newNotes);
};
const deleteNote = (id) => {
const newNotes = notes.filter((note) => note.id !== id);
setNotes(newNotes);
};
const editNote = (text, title, id) => {
const editDate = new Date();
const editedNote = {
id: nanoid(),
title: title,
text: text,
date: editDate.toDateString(),
};
const editedNotes = notes.map((note) => {
if (note.id == id) {
return editedNote;
}
return note;
});
setNotes(editedNotes);
};
return (
<div className="container">
<AddNote handleAddNote={addNote} />
<NotesList
notes={notes}
handleAddNote={addNote}
handleDeleteNote={deleteNote}
editNote={editNote}
updateNote={updateNote}
/>
</div>
);
};
export default App;
NotesList.js
import Note from "./Note";
import React, { useState } from "react";
import MyModal from "./Modal";
const NotesList = ({ notes, handleDeleteNote, updateNote })=> {
const [open, setOpen] = useState(false);
const [note, setNote] = useState({});
const handleOpen = (id) => {
setNote(notes.filter((note) => note.id === id)[0]);
setOpen(true);
};
const handleClose = () => {
setNote({});
setOpen(false);
};
const clickedTodo = useState({});
return (
<div className="notes-list">
<div className="blank-note"></div>
<div className="existing-notes">
<MyModal
note={note}
clickedTodo={clickedTodo}
handleClose={handleClose}
open={open}
updateNote={updateNote}
/>
{notes.map((note) => (
<Note
id={note.id}
title={note.title}
text={note.text}
date={note.date}
handleOpen={handleOpen}
handleDeleteNote={handleDeleteNote}
/>
))}
</div>
</div>
);
};
export default NotesList;
AddNote.js
import { useState } from "react";
import React from "react";
const AddNote = ({ handleAddNote, isUpdate, note, updateNote }) => {
const [noteTitle, setNoteTitle] = useState("");
const [noteText, setNoteText] = useState("");
const characterLimit = 300;
const handleChange = (event) => {
if (characterLimit - event.target.value.length >= 0) {
setNoteText(event.target.value);
}
};
const handleChange2 = (event) => {
if (characterLimit - event.target.value.length >= 0) {
setNoteTitle(event.target.value);
}
};
const handleSaveClick = () => {
// if (!isUpdate) then do this
// if (!isUpdate) {
(noteText.trim().length > 0)
handleAddNote(noteTitle, noteText);
setNoteText("");
setNoteTitle("");
// } else updateNote(note.id)
// else we use all of the info we have gotten
// we call update note with note.id
};
return (
<div className="note new">
<h2>Add note</h2>
<textarea className="new-text-title"
placeholder={!isUpdate?"Add a title...":note.title}
value={noteTitle}
onChange={handleChange2}
></textarea>
<textarea className="new-text-body"
cols="8"
rows="10"
placeholder={!isUpdate?"Type your note here...":note.text}
value={noteText}
onChange={handleChange}
></textarea>
<div className="note-footer">
<small>Characters remaining: {characterLimit - noteText.length}</small>
<button className="save" onClick={handleSaveClick}>
<strong>Save</strong>
</button>
</div>
</div>
);
};
export default AddNote;
Note.js
import { MdDeleteForever } from "react-icons/md";
const Note = (props) => {
const { id, title, text, date, handleOpen, handleDeleteNote } = props;
const handleOpenModal = (id) => {
handleOpen(id);
};
return (
<div className="note">
<div className="note-upper" onClick={() => handleOpenModal(id)}>
<p className="title">
<textarea className="text-title">{title}</textarea>
</p>
<textarea className="text-body">{text}</textarea>
</div>
<div className="note-footer">
<div className="footer-left" onClick={() => handleOpenModal(id)}>
<small>{date}</small>
</div>
<div className="footer-right">
<MdDeleteForever
onClick={() => {
if (window.confirm("Delete this note?")) {
handleDeleteNote(id);
}
}}
className="delete-icon"
size="1.3em"
/>
</div>
</div>
</div>
);
};
export default Note;
Modal.js
import React, { useState } from "react";
import { Modal, Box } from "#mui/material";
import Note from "./Note";
export default function MyModal(props) {
const { open, handleClose, note, updateNote } = props;
return (
<div onClose={console.log("closing")}>
<Modal open={open} onClose={handleClose}>
<Box
sx={{
position: "relative",
top: "50%",
left: "32%",
outline: "none",
}}
>
<Note
updateNote={updateNote}
note={note}
id={note.id}
title={note.title}
text={note.text}
date={note.date}
/>
</Box>
</Modal>
</div>
);
}
Your Modal.js requires updateNote prop, but in App.js you don't supply it to NotesList.js, thus the parent prop of MyModal.js has no such prop:
<NotesList
notes={notes}
handleAddNote={addNote}
handleDeleteNote={deleteNote}
editNote={editNote}
/>
And later in NotesList.js:
<MyModal
note={note}
clickedTodo={clickedTodo}
handleClose={handleClose}
open={open}
updateNote={updateNote} // this is missing because you are not
// passing this prop from the App component
/>

How can I create an instance of an Object in React..?

I am very new to react and javascript, but I am trying to build a simple ToDo App. It wasn't complicated until I wanted to read data from a file and to display that data on the screen. The problem is that I don't know how to create a new Todo object to pass it as parameter for addTodo function.. Thaaank you all and hope you can help me!!
I will let the code here (please see the -loadFromFile- function, there is the problematic place:
import React, { useState } from 'react';
import TodoForm from './TodoForm';
import Todo from './Todo';
import data from './data/data.json'
function TodoList() {
const [todos, setTodos] = useState([]);
const loadFromFile = data.map( ( data) => {
const newTodo = addTodo(new Todo(data.id,data.text));
return ( {newTodo} )});
const addTodo = todo => {
if (!todo.text || /^\s*$/.test(todo.text)) {
return;
}
const newTodos = [todo, ...todos];
setTodos(newTodos);
console.log(...todos);
};
const updateTodo = (todoId, newValue) => {
if (!newValue.text || /^\s*$/.test(newValue.text)) {
return;
}
setTodos(prev => prev.map(item => (item.id === todoId ? newValue : item)));
};
const removeTodo = id => {
const removedArr = [...todos].filter(todo => todo.id !== id);
setTodos(removedArr);
};
const completeTodo = id => {
let updatedTodos = todos.map(todo => {
if (todo.id === id) {
todo.isComplete = !todo.isComplete;
}
return todo;
});
setTodos(updatedTodos);
};
return (
<>
<TodoForm onSubmit={addTodo} />
{loadFromFile}
<Todo
todos={todos}
completeTodo={completeTodo}
removeTodo={removeTodo}
updateTodo={updateTodo}
/>
</>
);
}
export default TodoList;
I want to create new instance of Todo object. I tried many times, many different forms, but still doesn't work. I have an id and a text from the data.json file. I want to create that instance of Todo object with these two values. But how?
import React, { useState } from 'react';
import TodoForm from './TodoForm';
import EditIcon from '#material-ui/icons/Edit';
import DeleteIcon from '#material-ui/icons/Delete';
const Todo = ({ todos, completeTodo, removeTodo, updateTodo }) => {
const [edit, setEdit] = useState({
id: null,
value: ''
});
const submitUpdate = value => {
updateTodo(edit.id, value);
setEdit({
id: null,
value: ''
});
};
if (edit.id) {
return <TodoForm edit={edit} onSubmit={submitUpdate} />;
}
return todos.map((todo, index) => (
<div
className={todo.isComplete ? 'todo-row complete' : 'todo-row'}
key={index}
>
<p> <div key={todo.id} onClick={() => completeTodo(todo.id)}>
{todo.text}
</div>
</p>
<div className='icons'>
<DeleteIcon fontSize="small"
onClick={() => removeTodo(todo.id)}
className='delete-icon'
/>
<EditIcon
onClick={() => setEdit({ id: todo.id, value: todo.text })}
className='edit-icon'
/>
</div>
</div>
));
};
export default Todo;
import React, { useState, useEffect, useRef } from 'react';
import { Fab, IconButton } from "#material-ui/core";
import AddIcon from '#material-ui/icons/Add';
function TodoForm(props) {
const [input, setInput] = useState(props.edit ? props.edit.value : '');
const inputRef = useRef(null);
useEffect(() => {
inputRef.current.focus();
});
const handleChange = e => {
setInput(e.target.value);
};
const handleSubmit = e => {
e.preventDefault();
props.onSubmit({
id: Math.floor(Math.random() * 10000),
text: input
});
setInput('');
};
return (
<form onSubmit={handleSubmit} className='todo-form'>
{props.edit ? (
<>
<textarea cols="10"
placeholder='Update item'
value={input}
onChange={handleChange}
name='text'
ref={inputRef}
className='todo-input edit'
/>
<button onClick={handleSubmit} className='todo-button edit'>
Save
</button>
</>
) : (
<>
<input
placeholder='Add item'
value={input}
onChange={handleChange}
name='text'
className='todo-input'
ref={inputRef}
/>
<Fab color="primary" aria-label="add">
< AddIcon onClick={handleSubmit} fontSize="small" />
</Fab>
</>
)}
</form>
);
}
export default TodoForm;
Issue
Ah, I see what you are getting at now, you are wanting to load some list of todos from an external file. The main issue I see in your code is that you are attempting to call/construct a Todo React component manually and this simply isn't how React works. You render data/state/props into JSX and pass this to React and React handles instantiating the components and computing the rendered DOM.
const loadFromFile = data.map((data) => {
const newTodo = addTodo(new Todo(data.id, data.text));
return ({newTodo});
});
Todo shouldn't be invoked directly, React handles this.
Solution
Since it appears the data is already an array of objects with the id and text properties, it conveniently matches what you store in state. You can simply pass data as the initial todos state value.
const [todos, setTodos] = useState(data);
If the data wasn't readily consumable you could create an initialization function to take the data and transform/map it to the object shape your code needs.
const initializeState = () => data.map(item => ({
id: item.itemId,
text: item.dataPayload,
}));
const [todos, setTodos]= useState(initializeState);
Running Example:
import data from "./data.json";
function TodoList() {
const [todos, setTodos] = useState(data); // <-- initial state
const addTodo = (text) => {
if (!text || /^\s*$/.test(text)) {
return;
}
setTodos((todos) => [todo, ...todos]);
};
const updateTodo = (id, newTodo) => {
if (!newTodo.text || /^\s*$/.test(newTodo.text)) {
return;
}
setTodos((todos) => todos.map((todo) => (todo.id === id ? newTodo : todo)));
};
const removeTodo = (id) => {
setTodos((todos) => todos.filter((todo) => todo.id !== id));
};
const completeTodo = (id) => {
setTodos((todos) =>
todos.map((todo) =>
todo.id === id
? {
...todo,
isComplete: !todo.isComplete
}
: todo
)
);
};
return (
<>
<TodoForm onSubmit={addTodo} />
<Todo
todos={todos}
completeTodo={completeTodo}
removeTodo={removeTodo}
updateTodo={updateTodo}
/>
</>
);
}

Get an Error that .filter is not a function

I have tried to create an autocomplete suggestion box from an Thailand's province database URL.
This is my source code. I export this to App.js in src directory
import React, { useEffect, useState, useRef } from "react";
const Test = () => {
const [display, setDisplay] = useState(false);
const [singleProvince, setSingleProvince] = useState([]);
const [singleProvinceData, setSingleProvinceData] = useState([]);
const [search, setSearch] = useState("");
const wrapperRef = useRef(null);
const province_dataBase_url = 'https://raw.githubusercontent.com/earthchie/jquery.Thailand.js/master/jquery.Thailand.js/database/raw_database/raw_database.json'
useEffect(() => {
const promises = new Array(20).fill(fetch(province_dataBase_url)
.then((res) => {
return res.json().then((data) => {
const createSingleProvince = data.filter( (each) => {
if (false == (singleProvince.includes(each.province))) {
setSingleProvince(singleProvince.push(each.province))
setSingleProvinceData(singleProvinceData.push(each))
}
})
return data;
}).catch((err) => {
console.log(err);
})
}))
}, [])
useEffect(() => {
window.addEventListener("mousedown", handleClickOutside);
return () => {
window.removeEventListener("mousedown", handleClickOutside);
};
});
const handleClickOutside = event => {
const { current: wrap } = wrapperRef;
if (wrap && !wrap.contains(event.target)) {
setDisplay(false);
}
};
const updateProvince = inputProvince => {
setSearch(inputProvince);
setDisplay(false);
};
return (
<div ref={wrapperRef} className="flex-container flex-column pos-rel">
<input
id="auto"
onClick={() => setDisplay(!display)}
placeholder="Type to search"
value={search}
onChange={event => setSearch(event.target.value)}
/>
{display && (
<div className="autoContainer">
{ singleProvinceData
.filter( ({province}) => province.indexOf(search.toLowerCase()) > -1)
.map( (each,i) => {
return (
<div
onClick={() => updateProvince(each.province)}
className="singleProvinceData"
key={i}
tabIndex="0"
>
<span>{each.province}</span>
</div>
)
})}
</div>
)}
</div>
);
}
export default Test
When click on an input box, the console says "TypeError: singleProvinceData.filter is not a function"
enter image description here
I cannot find out what's wrong with my code
The issue is with the "singleProvinceData" state is not set correctly.
you cannot push data directly into the state.
useEffect(() => {
const promises = new Array(20).fill(fetch(province_dataBase_url)
.then((res) => {
return res.json().then((data) => {
const shallowSingleProvinceList = [];
const shallowSingleProvinceDataList = [];
const createSingleProvince = data.filter( (each) => {
if (false == (singleProvince.includes(each.province))) {
shallowSingleProvinceList.push(each.province)
shallowSingleProvinceDataList.push(each)
}
})
setSingleProvince(shallowSingleProvinceList)
setSingleProvinceData(shallowSingleProvinceDataList)
return data;
}).catch((err) => {
console.log(err);
})
}))
}, [])
You can show the data conditionally
{display && (
<div className="autoContainer">
{ singleProvinceData && singleProvinceData
.filter( ({province}) => province.indexOf(search.toLowerCase()) > -1)
.map( (each,i) => {
return (
<div
onClick={() => updateProvince(each.province)}
className="singleProvinceData"
key={i}
tabIndex="0"
>
<span>{each.province}</span>
</div>
)
})}
</div>
)}

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