I have a React notes app that has a delete button, and a state for user confirmation of deletion.
Once user confirms, the 'isConfirmed' state is updated to true and deletes the item from MongoAtlas and removes from notes array in App.jsx.
The problem is, the note that takes the index (through notes.map() in app.jsx I'm assuming) of the deleted notes position in the array has the 'isConfirmed' state set to true without calling setState. Thus, bugging out my delete button to not work for that specific note until page refresh.
I've included relevant code from my Delete Component:
function DeletePopup(props) {
const mountedRef = useRef(); //used to stop useEffect call on first render
const [isConfirmed, setIsConfirmed] = useState(false);
const [show, setShow] = useState(false);
function confirmDelete() {
// console.log("user clicked confirm");
setIsConfirmed(true);
// console.log(isConfirmed);
handleClose();
}
useEffect(() => {
// console.log("delete useEffect() run");
if (mountedRef.current) {
props.deleteNote(isConfirmed);
}
mountedRef.current = true;
}, [isConfirmed]);
Note Component:
function Note(props) {
function deleteNote(isConfirmed) {
props.deleteNote(props.id, { title: props.title, content: props.content }, isConfirmed);
console.log("note.deleteNote ran with confirmation boolean: " + isConfirmed);
}
return <Draggable
disabled={dragDisabled}
onStop={finishDrag}
defaultPosition={{ x: props.xPos, y: props.yPos }}
>
<div className='note'>
<h1>{props.title}</h1>
<p>{props.content}</p>
<button onClick={handleClick}>
{dragDisabled ? <LockIcon /> : <LockOpenIcon />}
</button>
<EditPopup title={props.title} content={props.content} editNote={editNote} />
<DeletePopup deleteNote={deleteNote} />
</div>
</Draggable>
}
App Component:
function App() {
const [notes, setNotes] = useState([]);
function deleteNote(id, deleteNote, isConfirmed) {
if (!isConfirmed) return;
axios.post("/api/note/delete", deleteNote)
.then((res) => setNotes(() => {
return notes.filter((note, index) => {
return id !== index;
});
}))
.catch((err) => console.log(err));
}
return (
<div id="bootstrap-override">
<Header />
<CreateArea
AddNote={AddNote}
/>
{notes.map((note, index) => {
return <Note
key={index}
id={index}
title={note.title}
content={note.content}
xPos={note.xPos}
yPos={note.yPos}
deleteNote={deleteNote}
editNote={editNote}
/>
})}
<Footer />
</div>);
}
I've tried inserting log statements everywhere and can't figure out why this is happening.
I appreciate any help, Thanks!
EDIT: I changed my Notes component to use ID based on MongoAtlas Object ID and that fixed the issue. Thanks for the help!
This is because you are using the index as key.
Because of that when you delete an element you call the Array.filter then you the elements can change the index of the array which when React tries to rerender the notes and as the index changes it cannot identify the note you've deleted.
Try using a unique id (e.g. an id from the database or UUID) as a key instead.
I hope it solves your problem!
Related
I have a parent component with a handler function:
const folderRef = useRef();
const handleCollapseAllFolders = () => {
folderRef.current.handleCloseAllFolders();
};
In the parent, I'm rendering multiple items (folders):
{folders &&
folders.map(folder => (
<CollapsableFolderListItem
key={folder.id}
name={folder.name}
content={folder.content}
id={folder.id}
ref={folderRef}
/>
))}
In the child component I'm using the useImperativeHandle hook to be able to access the child function in the parent:
const [isFolderOpen, setIsFolderOpen] = useState(false);
// Collapse all
useImperativeHandle(ref, () => ({
handleCloseAllFolders: () => setIsFolderOpen(false),
}));
The problem is, when clicking the button in the parent, it only collapses the last opened folder and not all of them.
Clicking this:
<IconButton
onClick={handleCollapseAllFolders}
>
<UnfoldLessIcon />
</IconButton>
Only collapses the last opened folder.
When clicking the button, I want to set the state of ALL opened folders to false not just the last opened one.
Any way to solve this problem?
You could create a "multi-ref" - ref object that stores an array of every rendered Folder component. Then, just iterate over every element and call the closing function.
export default function App() {
const ref = useRef([]);
const content = data.map(({ id }, idx) => (
<Folder key={id} ref={(el) => (ref.current[idx] = el)} />
));
return (
<div className="App">
<button
onClick={() => {
ref.current.forEach((el) => el.handleClose());
}}
>
Close all
</button>
{content}
</div>
);
}
Codesandbox: https://codesandbox.io/s/magical-cray-9ylred?file=/src/App.js
For each map you generate new object, they do not seem to share state. Try using context
You are only updating the state in one child component. You need to lift up the state.
Additionally, using the useImperativeHandle hook is a bit unnecessary here. Instead, you can simply pass a handler function to the child component.
In the parent:
const [isAllOpen, setAllOpen] = useState(false);
return (
// ...
{folders &&
folders.map(folder => (
<CollapsableFolderListItem
key={folder.id}
isOpen={isAllOpen}
toggleAll={setAllOpen(!isAllOpen)}
// ...
/>
))}
)
In the child component:
const Child = ({ isOpen, toggleAll }) => {
const [isFolderOpen, setIsFolderOpen] = useState(false);
useEffect(() => {
setIsFolderOpen(isOpen);
}, [isOpen]);
return (
// ...
<IconButton
onClick={toggleAll}
>
<UnfoldLessIcon />
</IconButton>
)
}
I am new to React and trying to learn more by creating projects. I made an API call to display some images to the page and I would like to create a like button/icon for each image that changes to red when clicked. However, when I click one button all of the icons change to red. I believe this may be related to the way I have set up my state, but can't seem to figure out how to target each item individually. Any insight would be much appreciated.
`
//store api data
const [eventsData, setEventsData] = useState([]);
//state for like button
const [isLiked, setIsLiked] = useState(false);
useEffect(() => {
axios({
url: "https://app.ticketmaster.com/discovery/v2/events",
params: {
city: userInput,
countryCode: "ca",
},
})
.then((response) => {
setEventsData(response.data._embedded.events);
})
.catch((error) => {
console.log(error)
});
});
//here i've tried to filter and target each item and when i
console.log(event) it does render the clicked item, however all the icons
change to red at the same time
const handleLikeEvent = (id) => {
eventsData.filter((event) => {
if (event.id === id) {
setIsLiked(!isLiked);
}
});
};
return (
{eventsData.map((event) => {
return (
<div key={event.id}>
<img src={event.images[0].url} alt={event.name}></img>
<FontAwesomeIcon
icon={faHeart}
className={isLiked ? "redIcon" : "regularIcon"}
onClick={() => handleLikeEvent(event.id)}
/>
</div>
)
`
Store likes as array of ids
const [eventsData, setEventsData] = useState([]);
const [likes, setLikes] = useState([]);
const handleLikeEvent = (id) => {
setLikes(likes.concat(id));
};
return (
<>
{eventsData.map((event) => {
return (
<div key={event.id}>
<img src={event.images[0].url} alt={event.name}></img>
<FontAwesomeIcon
icon={faHeart}
className={likes.includes(event.id) ? "redIcon" : "regularIcon"}
onClick={() => handleLikeEvent(event.id)}
/>
</div>
);
})}
</>
);
Your issue is with your state, isLiked is just a boolean true or false, it has no way to tell the difference between button 1, or button 2 and so on, so you need a way to change the css property for an individual button, you can find one such implementation by looking Siva's answer, where you store their ids in an array
I'm pulling stuff from my database using Firestore. When I log inside the function that pulls the data, the array has the data. When I log in my main component, it also has. But for some reason, .map doesn't work, and when I try array.length it returns 0. I was using a map, but then I changed it to use a function to try to get the error.
export default function Search() {
const [searchedData, setSearchedData] = useState([]);
const [loading, setLoading] = useState(true);
const [noBook, setNoBook] = useState(false);
const [showBooks, setShowBooks] = useState(false);
const link = useLocation();
useEffect(() => {
const srch = link.pathname.substring(8);
loadSearchBooks(srch);
}, [link]);
async function loadSearchBooks(srch) {
try {
const bookArray = await getSearchedBooks(srch);
bookArray ? setShowBooks(true) : setNoBook(true);
setSearchedData(bookArray);
} catch (e) {
setSearchedData(null);
} finally {
setLoading(false);
}
}
function renderBooks() {
console.log(searchedData);
const l = searchedData.length;
return l;
}
return (
<div>
<Navbar />
<div className={searchBookWrapper}>
{loading && 'Carregando'}
{showBooks && renderBooks()}
{noBook && <BookCardItem />}
</div>
</div>
);
}
When doing this, console.log(searchedData) returns the array, but const l = searchedData.length shows just a 0. When I search again, the number changes to 12 for a moment right when it's about to change. This is the previous code:
return (
<div>
<Navbar />
<div className={searchBookWrapper}>
{loading && 'Carregando'}
{showBooks &&
searchedData.map(({ afn, aln, notes, quant, title }, index) => {
return (
<BookCardItem
key={title}
firstName={afn}
lastName={aln}
notes={notes}
quant={quant}
title={title}
bookNumber={index}
/>
);
})}
{noBook && <BookCardItem />}
</div>
</div>
);
}
The same thing happened. The bookInfo appeared just for a moment when I searched again.
From the first code in this question, this is the console:
Console - one empty array, then two filled ones
if useLocation is an API call or other async function, react prefers those to be in a useEffect. If they are not, it can give inconsistent results. Try putting useLocation inside a useEffect. If you only plan on useLocation firing once (and thus loadSearchedBooks only firing once) you can even put them in the same useEffect, just don't make them rerender based on the thing they update.
useEffect(() => {
useLocation().then(link => {
const srch = link.pathname.substring(8);
loadSearchBooks(srch);
}
}, []);
Hopefully, this will fix your problem.
So I'm doing a list in which you can add items. When you add them you have two options:
Delete the whole list
Delete a specific item.
But for some reason the "handeDelete" button is not working. Can somebody tell me what did I write wrong in the code?
The link to CodeSandbox is:
codesandbox
import { useState } from "react";
import uuid from "react-uuid";
export default function ItemList() {
const [items, setItems] = useState({ item: "" });
const [groceryList, setGroceryList] = useState([]);
function handleChange(value, type) {
setItems((prev) => {
return { ...prev, [type]: value };
});
}
function handleSubmit(e) {
e.preventDefault();
const newItem = { ...items, id: uuid() };
setGroceryList([...groceryList, newItem]);
setItems({ item: "" });
}
function handleDelete(id) {
setGroceryList(groceryList.filter((items) => items.id !== id));
}
return (
<>
<form autoComplete="off" onSubmit={handleSubmit}>
<input
type="text"
name="item"
id="item"
value={items.item}
onChange={(e) => handleChange(e.target.value, "item")}
/>
</form>
{groceryList.map((list) => {
return (
<div key={list.id}>
<ul>
<li> {list.item}</li>
</ul>
<button onClick={(id) => handleDelete()}>Delete</button>
</div>
);
})}
<button onClick={() => setGroceryList([])}>Clear</button>
</>
);
}
Your delete button definition is wrong:
<button onClick={() => handleDelete(list.id)}>Delete</button>
the parameter you are receiving from the click event is not the id. Since you are not working with the event args itselfy you can safely ignore it. The second mistake was, that you are not passing the id itself to your handleDelete function.
For learning purposes, humor yourself and print the event to the console, while developing:
<button onClick={(evt) => {
console.log(evt)
handleDelete(list.id)
}}>
Delete
</button>
This will show you, that the parameter, that you named id (and I renamend to evt), is in fact reacts Synthetic Event: https://reactjs.org/docs/events.html
I would like to delete selected item from list.
When I click on delete the right item get deleted from the list content but on UI I get always the list item fired.
I seems to keep track of JSX keys and show last values.
Here's a demo
const Holidays = (props) => {
console.log(props);
const [state, setState] = useState({ ...props });
useEffect(() => {
setState(props);
console.log(state);
}, []);
const addNewHoliday = () => {
const obj = { start: "12/12", end: "12/13" };
setState(update(state, { daysOffList: { $push: [obj] } }));
};
const deleteHoliday = (i) => {
const objects = state.daysOffList.filter((elm, index) => index != i);
console.log({ objects });
setState(update(state, { daysOffList: { $set: objects } }));
console.log(state.daysOffList);
};
return (
<>
<Header as="h1" content="Select Holidays" />
<Button
primary
icon={<AddIcon />}
text
content="Add new holidays"
onClick={() => addNewHoliday(state)}
/>
{state?.daysOffList?.map((elm, i) => {
console.log(elm.end);
return (
<Flex key={i.toString()} gap="gap.small">
<>
<Header as="h5" content="Start Date" />
<Datepicker
defaultSelectedDate={
new Date(`${elm.start}/${new Date().getFullYear()}`)
}
/>
</>
<>
<Header as="h5" content="End Date" />
<Datepicker
defaultSelectedDate={
new Date(`${elm.end}/${new Date().getFullYear()}`)
}
/>
</>
<Button
key={i.toString()}
primary
icon={<TrashCanIcon />}
text
onClick={() => deleteHoliday(i)}
/>
<span>{JSON.stringify(state.daysOffList)}</span>
</Flex>
);
})}
</>
);
};
export default Holidays;
Update
I'm trying to make a uniq id by adding timeStamp.
return (
<Flex key={`${JSON.stringify(elm)} ${Date.now()}`} gap="gap.small">
<>
<Header as="h5" content="Start Date" />
<Datepicker
defaultSelectedDate={
new Date(`${elm.start}/${new Date().getFullYear()}`)
}
/>
</>
<>
<Header as="h5" content="End Date" />
<Datepicker
defaultSelectedDate={
new Date(`${elm.end}/${new Date().getFullYear()}`)
}
/>
</>
<Button
primary
key={`${JSON.stringify(elm)} ${Date.now()}`}
icon={<TrashCanIcon />}
text
onClick={() => deleteHoliday(i)}
/>{" "}
</Flex>
);
I was hoping that the error disappear but still getting same behaviour
Issue
You are using the array index as the React key and you are mutating the underlying data array. When you click the second entry to delete it, the third element shifts forward to fill the gap and is now assigned the React key for the element just removed. React uses the key to help in reconciliation, if the key remains stable React bails on rerendering the UI.
You also can't console log state immediately after an enqueued state update and expect to see the updated state.
setState(update(state, { daysOffList: { $set: objects } }));
console.log(state.daysOffList);
React state updates are asynchronous and processed between render cycles. The above can, and will, only ever log the state value from the current render cycle, not the update enqueued for the next render cycle.
Solution
Use a GUID for each start/end data object. uuid is a fantastic package for this and has really good uniqueness guarantees and is incredibly simple to use.
import { v4 as uuidV4 } from 'uuid';
// generate unique id
uuidV4();
To specifically address the issues in your code:
Add id properties to your data
const daysOffList = [
{ id: uuidV4(), start: "12/12", end: "12/15" },
{ id: uuidV4(), start: "12/12", end: "12/17" },
{ id: uuidV4(), start: "12/12", end: "12/19" }
];
...
const addNewHoliday = () => {
const obj = {
id: uuidV4(),
start: "12/12",
end: "12/13",
};
setState(update(state, { daysOffList: { $push: [obj] } }));
};
Update handler to consume id to delete
const deleteHoliday = (id) => {
const objects = state.daysOffList.filter((elm) => elm.id !== id);
setState(update(state, { daysOffList: { $set: objects } }));
};
Use the element id property as the React key
{state.daysOffList?.map((elm, i) => {
return (
<Flex key={elm.id} gap="gap.small">
...
</Flex>
);
})}
Pass the element id to the delete handler
<Button
primary
icon={<TrashCanIcon />}
text
onClick={() => deleteHoliday(elm.id)}
/>
Use an useEffect React hook to log any state update
useEffect(() => {
console.log(state.daysOffList);
}, [state.daysOffList]);
Demo
Note: If you don't want (or can't) install additional 3rd-party dependencies then you can roll your own id generator. This will work in a pinch but you should really go for a real proven solution.
const genId = ((seed = 0) => () => seed++)();
genId(); // 0
genId(); // 1