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}
/>
</>
);
}
Related
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.
I am a beginner in react js programming. I'm trying to do the todo project, which is a classic project. When I delete or add an element from the list, the newly formed list appears on the screen by combining with the previous one, I will show it with a picture below. I did not understand the source of the eror so wanted to post it here to get some advices suggestions about why it is happening.Thank you.(I am getting and storing data in firebase firestore database)
Before Adding an element initial array state
After adding an element to the array.
I am using useState for array and using useEffect to get initial data
MainPage.js that contains form and the list components.
const MainPage = () => {
const [isLoading, setLoding] = useState(true);
const [array, setArray] = useState([]);
const sub = async (email) => {
var result = [];
await onSnapshot(doc(db, "users", email), (doc) => {
var data = doc.data().todos;
data.forEach((element) => {
Object.keys(element).map(() => {
result.push(element["title"]);
});
});
setArray(result);
setLoding(false);
});
};
useEffect(() => {
sub(auth.currentUser.email);
}, []);
const onAddToDo = (todoTitle) => {
setArray((prevAray) => {
return [...prevAray, todoTitle];
});
};
const onRemove = (title) => {
setArray((prevAray) => {
return [array.pop(array.indexOf(title))];
});
};
return (
<div>
{isLoading && <h1>Loading</h1>}
{!isLoading && (
<div>
<section>
<NavBar></NavBar>
<ToDoForm passData={onAddToDo} />
</section>
<section>
<CardList removeCards={onRemove} array={array} />
</section>
</div>
)}
</div>
);
};
export default MainPage;
Firebase.js that stores the firebase update methods
export const deleteItem = (title) => {
updateDoc(doc(db, "users", auth.currentUser.email), {
todos: arrayRemove({ title: title }),
});
};
export const addnewTodo = (title) => {
updateDoc(doc(db, "users", auth.currentUser.email), {
todos: arrayUnion({ title: title }),
});
};
TodoForm.js component
const ToDoForm = (props) => {
const [todoTitle, setTitle] = useState("");
const titleChangeHandler = (event) => {
setTitle(event.target.value);
};
const newTodoAdder = (event) => {
event.preventDefault();
addnewTodo(todoTitle);
props.passData(todoTitle);
};
return (
<div className="form_holder">
<div className="form_container">
<form onSubmit={newTodoAdder}>
<h3>Add Events</h3>
<label>Title</label>
<input
onChange={titleChangeHandler}
type="text"
placeholder="Title"
id="title"
></input>
<div className="holder">
<button type="sumbit">Add</button>
</div>
</form>
</div>
</div>
);
};
export default ToDoForm;
CardList.js component
const CardList = (props) => {
const array = props.array;
if (array.length === 0) {
return (
<div className="grid_container">
<h2>Found no todos</h2>
</div>
);
}
return (
<div className="grid_container">
{array.map((element, index) => {
return (
<Card
removeSelf={() => {
props.removeCards(element);
}}
key={index}
title={element}
/>
);
})}
</div>
);
};
export default CardList;
Card.js component
const Card = (props) => {
const handleRemove = (event) => {
event.preventDefault();
deleteItem(props.title);
props.removeSelf();
};
return (
<div className="card">
<h2 className="card__title">{props.title}</h2>
<button type="button" onClick={handleRemove}>
Delete
</button>
</div>
);
};
export default Card;
EDIT ;
Index.js file
import React from "react";
import ReactDOM from "react-dom/client";
import App from "./App";
import { BrowserRouter } from "react-router-dom";
const root = ReactDOM.createRoot(document.getElementById("root"));
root.render(
<BrowserRouter>
<App />
</BrowserRouter>
);
SOLUTION
I fixed the issue by changing the add and remove functions that were inside of MainPage.js file You can see the new versions bellow. Hope someday it will help somebody.
Use effect was called once all I had to do get the data again after a change...
New Remove and Add functions
const onAddToDo = (todoTitle) => {
console.log(todoTitle + " Added");
sub(auth.currentUser.email);
};
const onRemove = (title) => {
console.log(title + " Deleted");
sub(auth.currentUser.email);
};
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
}
I'm starting studying React and I was following this YouTube tutorial of a TO DO LIST using React.
https://www.youtube.com/watch?v=E1E08i2UJGI
My form loads perfectly, but if I write something and press any button I get the message: "completedTask is not a function". The same goes for buttons that call a function 'removeTask' and 'setEdit'.
I don't understand the reason I'm getting such error message. In the tutorial it works when the buttons are clicked. I've read in some forums that it would be related to the fact that you can't use map on Objects (non-array elements), but I didn't understand it very well and I don't know how to fix it. And the most mysterious parte: why does his code work and mine do not?
Could anybody please explain it?
Obs1: I found in another post that return tasks.tasks.map((task, index) solved the problem for 'task.map is not a function' error message in TASK.JS. I'm using it instead of return tasks.map((task, index) but I also didn't understant the reason.
Obs2: I don't think it makes any difference for the error message, but I used the button tag instead using React Icons as the video suggests.
=== TASKLIST.JS ===
import React, { useState } from 'react'
import Task from './Task'
import TaskForm from './TaskForm'
function TaskList() {
const [tasks, setTasks] = useState([]);
const addTask = task => {
if(!task.text || /^\s*$/.test(task.text)) {
return
}
const newTasks = [task, ...tasks];
setTasks(newTasks);
};
const updateTask = (taskId, newValue) => {
if(!newValue.text || /^\s*$/.test(newValue.text)) {
return
}
setTasks(prev => prev.map(item => (item.id === taskId ? newValue : item)));
};
const removeTask = id => {
const removeArr = [...tasks].filter(task => task.id !== id);
setTasks(removeArr)
};
const completedTask = id => {
let updatedTasks = tasks.map(task => {
if (task.id === id) {
task.isComplete = !task.isComplete
}
return task
})
setTasks(updatedTasks);
};
return (
<div>
<h1>Cabeçalho</h1>
<TaskForm onSubmit={addTask}/>
<Task
tasks={tasks}
completedTask={completedTask}
removeTask={removeTask}
updateTask={updateTask} />
</div>
)
}
export default TaskList
=== TASK.JS ===
import React, { useState } from 'react'
import TaskForm from './TaskForm'
function Task(tasks, completedTask, removeTask, updateTask) {
const [edit, setEdit] = useState({
id: null,
value: ''
})
const submitUpdate = value => {
updateTask(edit.id, value)
setEdit({
id: null,
value: ''
})
}
if (edit.id) {
return <TaskForm edit={edit} onSubmit={submitUpdate} />;
}
return tasks.tasks.map((task, index) => (
<div className={task.isComplete ? 'task-row complete' : 'task-row'} key={index}>
{task.text}
<div className="buttons">
<button onClick={() => completedTask(task.id)} className='completed-icon'>done</button>
<button onClick={() => removeTask(task.id)} className='delete-icon'>delete</button>
<button onClick={() => setEdit({id: task.id, value: task.text})} className='edit-icon'>edit</button>
</div>
</div>
))
};
export default Task
=== TASKFORM.JS ===
import React, { useState, useEffect, useRef } from 'react'
function TaskForm(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() * 1000),
text: input
});
setInput('');
};
return (
<form className="task-form" onSubmit={handleSubmit}>
{props.edit ? (
<>
<input type="text" placeholder="Update your task" value={input} name="text" className="task-input" onChange={handleChange} ref={inputRef}/>
<button className="task-button edit" onChange={handleChange}>Update a task</button>
</>
) : (
<>
<input type="text" placeholder="Add a new task" value={input} name="text" className="task-input" onChange={handleChange} ref={inputRef}/>
<button className="task-button" onChange={handleChange}>Add a task</button>
</>
)}
</form>
)
}
export default TaskForm
Try this:
function Task({ tasks, completedTask, removeTask, updateTask }) {
// ...
}
You can also do this (semantically equivalent):
function Task(props) {
const { tasks, completedTask, removeTask, updateTask } = props;
// ...
}
As mentioned here:
The first parameter will be props object itself. You need to destructure the object.
You can read more about object destructuring here.
i'm trying to work on a todo app with the option of editing.
the goal is to click on the edit button and that'll open an input field, type the new editted text and then have two choices , save the changes or not.
i've managed to write the code for it to open the input field, and to be able to click on the button to not save changes ,but what happens is that it opens the input field for all of the todos ,and whenever i try to update the value of the specific todo i get the error "todos.map is not a function".
Here's the TodoList.js
import Todo from "./Todo";
import AddTodo from "./AddTodo";
import { v4 as uuidv4 } from "uuid";
const TodoList = () => {
//Handlers Add/Remove/RemoveAll/Edit
const addTodoHandler = (input) => {
setTodos([
...todos,
{
name: input,
id: uuidv4(),
},
]);
};
const changeEditMode = (id) => {
setEditMode(!editMode);
console.log(id);
};
const removeTodosHandler = () => {
if (window.confirm("Are you sure you want to delete everything?")) {
setTodos([]);
}
};
const removeTodoHandler = (id) => {
setTodos(todos.filter((todo) => todo.id !== id));
};
const updateValue = (id) => {
inputRef.current.focus();
setEditMode(!editMode);
setTodos({ name: inputRef.current.value });
};
//Todo list states.
const inputRef = useRef("");
const [todos, setTodos] = useState([]);
const [editMode, setEditMode] = useState(false);
return (
<div>
<div>
{todos.map((todo) => {
return (
<div>
{editMode ? (
<div>
{" "}
<input
type="text"
defaultValue={todo.name}
ref={inputRef}
></input>
<button onClick={(e) => updateValue(todo.id)}>ok</button>
<button onClick={(e) => setEditMode(!editMode)}>x</button>
</div>
) : (
<div></div>
)}
<Todo name={todo.name} key={todo.id} />
<button onClick={() => removeTodoHandler(todo.id)}>X</button>
<button onClick={(e) => changeEditMode(todo.id)}>Edit</button>
</div>
);
})}
</div>
<AddTodo
handleAddTodo={addTodoHandler}
removeTodosHandler={removeTodosHandler}
revemoveTodoHandler={removeTodoHandler}
/>
</div>
);
};
export default TodoList;
and here's the Todo.js
const Todo = ({ name }) => {
return (
<div>
<div>{name}</div>
</div>
);
};
export default Todo;
Any help appreciated!
Your updateValue function is setting your todos to an object. So it gives you that error because you can't use map method for objects.
In your updateValue method you are setting your todoList to and object.
const updateValue = (id) => {
inputRef.current.focus();
setEditMode(!editMode);
setTodos({ name: inputRef.current.value });
};
But what you have to do is first find out the item with the id and then update the name property of that object and then again set the new array to setTodos setter.
Like this:
const clonedTodos = todos;
const todoIndex = clonedTodos.findIndex((todo) => todo.id === id);
const updatedTodo = {
...clonedTodos[todoIndex],
name: inputRef.current.value,
};
const updatedTodos = [...clonedTodos];
updatedTodos[todoIndex] = updatedTodo;
setTodos(updatedTodos);