I have a rather simple requirement which is turning out to be quite complex for me. I'm developing a basic todo app with following UI:
Design
Now I need to update the array of object such that only the text of specific item should be updated. Here is my attempt but it just adds a new component on every key press:
import React, {useState} from "react";
const DynamicInput = () => {
const [todos, setTodos] = useState([])
const onAddClick = () => {
setTodos(prevState => {
return [...prevState, {id: prevState.length + 1, text: "", up: "↑", down: "↓", del: "x"}]
})
}
const onValueUpdate = (id) => (event) => {
let tempObject = todos[id]
setTodos(prevState => {
return [...prevState, {
id: id,
text: event.target.value,
up: "Up",
down: "Down",
del: "x"
}];
})
}
const onUpArrow = (event) => {
console.log("On up")
}
const onDownArrow = (event) => {
console.log("On down")
}
const onDeleteArrow = (event) => {
console.log("On delete")
}
return (
<>
<button onClick={onAddClick}>+</button>
{todos.map(todo => {
return(
<div key={todo.id}>
<input onChange={onValueUpdate(todo.id)} value={todo.text}></input>
<button onClick={onUpArrow}>{todo.up}</button>
<button onClick={onDownArrow}>{todo.down}</button>
<button onClick={onDeleteArrow}>{todo.del}</button>
</div>)
})}
</>
);
};
export default DynamicInput;
To simply solve your problem you can change your onValueUpdate() method to this :
const onValueUpdate = (id) => (event) => {
setTodos(prevState => {
let data = [...prevState];
let indexOfTodo = data.findIndex(todo => todo.id === id);
data[indexOfTodo] = {
...data[indexOfTodo],
text: event.target.value,
};
return data;
});
};
Related
I am building a chat app and using graphQl-ws and Im having issues with a function firing multiple times. My problem is why does doSubscriptionAction fire repeatedly and how to prevent that.
component
const ChatRooms = ({ selectConvo }: SelectConvoProp) => {
const {
data: { _id },
} = auth.getUser();
const { subscribeToMore, data } = useQuery(QUERY_CONVOS);
return (
<div className="sb-convos-wrapper">
<h3 className="sb-title">Chat Rooms - {data?.convos?.length}</h3>
<Convos
convos={data?.convos}
selectConvo={selectConvo}
subscribeToConvos={() => {
subscribeToMore({
document: SUBSCRIBE_CONVOS,
variables: { _id: _id },
updateQuery: (prev, { subscriptionData }) => {
if (!subscriptionData.data) return prev;
return doSubscriptionAction(prev, { subscriptionData });
},
});
}}
/>
</div>
);
};
subscribeToMoreActions function
/// this function take the subscription payload and adds it to the prev query cache
const addToPrev = (prev: any, { subscriptionData }: any) => {
const newConvo = subscriptionData.data.convo;
const updatedConvos = Object.assign(
{},
{
convos: [...prev.convos, newConvo],
}
);
return updatedConvos;
};
const removeFromPrev = (prev: any, { subscriptionData }: any) => {
const deletedConvo = subscriptionData.data.convo;
const filteredConvos = prev.convos.filter(
(convo: any) => convo._id === deletedConvo._id
);
const updatedConvos = Object.assign(
{},
{
convos: [...filteredConvos],
}
);
console.log(updatedConvos);
return updatedConvos;
};
/// this function delegates which function to use based off action
export const doSubscriptionAction = (prev: any, { subscriptionData }: any) => {
if (subscriptionData.data.convo.action === "create") {
return addToPrev(prev, { subscriptionData });
}
if (subscriptionData.data.convo.action === "delete") {
return removeFromPrev(prev, { subscriptionData });
}
};
convos component
const Convos = ({ convos, selectConvo, subscribeToConvos }: ConvosProp) => {
useEffect(() => {
subscribeToConvos();
}, [subscribeToConvos]);
const [deleteConvo] = useMutation(DELETE_CONVO, {
refetchQueries: [{ query: QUERY_CONVOS }, "Convos"],
});
const handleDelete = async (_id: string) => {
await deleteConvo({ variables: { _id } });
};
return (
<div className="sb-chat-container">
{convos?.map((convo: ConvoType, i: number) => {
return (
<div className="sb-chat-item-container" key={`chatRoom ${i}`}>
<div
className="sb-chat-content-container"
onClick={() => selectConvo(convo)}
>
<div className={"sb-chat-content-container-top"}>
<h5>{convo.roomName}</h5>
</div>
<LastMessage convo={convo} />
</div>
<button onClick={() => handleDelete(convo._id)}>X</button>
</div>
);
})}
</div>
);
};
TLDR: doSubscriptionAction fires multiple times adding multiple instances of created room to other user.
I have a simple problem here which I can't figure out. I wanted to hide menus depending on the condition.
For example if status contains at least one "Unlinked". "All unlinked images" menu should appear. I did used .some and I wonder why it doesn't return a boolean.
Codesandbox is here Click here
const showDeleteAllInvalidButton = () => {
const productImages = products?.flatMap((product) =>
product.productImages.filter((image) => image?.status)
);
return productImages?.some((e) => e?.status === "Invalid");
};
const showDeleteAllUnlinkedButton = () => {
const productImages = products?.flatMap((product) =>
product.productImages.filter((image) => image?.status)
);
return productImages?.some((e) => e?.status === "Unlinked");
};
The methods do return a boolean. But in the menus array you are assigning a function reference not the result -
show: showDeleteAllInvalidButton // function reference
show is now assigned a reference to the function showDeleteAllInvalidButton not the result of productImages?.some. You need to invoke the functions when assigning -
show: showDeleteAllInvalidButton() // result of productImages?.some
In your menus object you have a key that contains a function, so if you want this function to filter out your elements you need to execute the show method in side the filter method.
import React, { useState } from "react";
import Button from "#mui/material/Button";
import MenuItem from "#mui/material/MenuItem";
import KeyboardArrowDownIcon from "#mui/icons-material/KeyboardArrowDown";
import CustomMenu from "../../Menu";
const products = [
{
productName: "Apple",
productImages: [
{
status: "Unlinked"
}
]
},
{
productName: "Banana",
productImages: [
{
status: "Unlinked"
}
]
},
{
productName: "Mango",
productImages: [
{
status: "Unlinked"
},
{
status: "Unlinked"
}
]
}
];
const HeaderButtons = () => {
const [anchorEl, setAnchorEl] = useState(null);
const open = Boolean(anchorEl);
const handleClick = (event) => {
setAnchorEl(event.currentTarget);
};
const handleClose = () => {
setAnchorEl(null);
};
const showDeleteAllInvalidButton = () => {
const productImages = products?.flatMap((product) =>
product.productImages.filter((image) => image?.status)
);
return productImages?.some((e) => e?.status === "Invalid");
};
const showDeleteAllUnlinkedButton = () => {
const productImages = products?.flatMap((product) =>
product.productImages.filter((image) => image?.status)
);
return productImages?.some((e) => e?.status === "Unlinked");
};
const menus = [
{
id: 1,
name: "Invalid images",
action: () => {
handleClose();
},
show: showDeleteAllInvalidButton
},
{
id: 2,
name: "Unlinked images",
action: () => {
handleClose();
},
show: showDeleteAllUnlinkedButton
},
{
id: 3,
name: "All images",
action: () => {
handleClose();
},
show: () => true // not that I changed it to a function for consistency, but you can check for type in the filter method instead of running afunction
}
];
return (
<div>
<Button
color="error"
aria-haspopup="true"
aria-expanded={open ? "true" : undefined}
variant="outlined"
onClick={handleClick}
endIcon={<KeyboardArrowDownIcon />}
>
Options
</Button>
<CustomMenu anchorEl={anchorEl} open={open} onClose={handleClose}>
{menus
.filter((e) => e.show()) // here is your mistake
.map(
({
id = "",
action = () => {},
icon = null,
name = "",
divider = null
}) => (
<>
<MenuItem key={id} onClick={action} disableRipple>
{icon}
{name}
</MenuItem>
{divider}
</>
)
)}
</CustomMenu>
</div>
);
};
export default HeaderButtons;
In your code, it will always render because your filter functions are evaluating as truth.
I am building a clone of the Google Keep app with react js. I added all the basic functionality (expand the create area, add a note, delete it) but I can't seem to manage the edit part. Currently I am able to edit the inputs and store the values in the state, but how can I replace the initial input values for the new values that I type on the input?
This is Note component
export default function Note(props) {
const [editNote, setEditNote] = useState(false);
const [currentNote, setCurrentNote] = useState({
id: props.id,
editTitle: props.title,
editContent: props.content,
});
const handleDelete = () => {
props.deleteNote(props.id);
};
const handleEdit = () => {
setEditNote(true);
setCurrentNote((prevValue) => ({ ...prevValue }));
};
const handleInputEdit = (event) => {
const { name, value } = event.target;
setCurrentNote((prevValue) => ({
...prevValue,
[name]: value,
}));
};
const updateNote = () => {
setCurrentNote((prevValue, id) => {
if (currentNote.id === id) {
props.title = currentNote.editTitle;
props.content = currentNote.editContent;
} else {
return { ...prevValue };
}
});
setEditNote(false);
};
return (
<div>
{editNote ? (
<div className='note'>
<input
type='text'
name='edittitle'
defaultValue={currentNote.editTitle}
onChange={handleInputEdit}
className='edit-input'
/>
<textarea
name='editcontent'
defaultValue={currentNote.editContent}
row='1'
onChange={handleInputEdit}
className='edit-input'
/>
<button onClick={() => setEditNote(false)}>Cancel</button>
<button onClick={updateNote}>Save</button>
</div>
) : (
<div className='note' onDoubleClick={handleEdit}>
<h1>{props.title}</h1>
<p>{props.content}</p>
<button onClick={handleDelete}>DELETE</button>
</div>
)}
</div>
);
}
And this is the Container component where I am renderind the CreateArea and mapping the notes I create. I tried to map the notes again with the new values but it wasn't working.
export default function Container() {
const [notes, setNotes] = useState([]);
const addNote = (newNote) => {
setNotes((prevNotes) => {
return [...prevNotes, newNote];
});
};
const deleteNote = (id) => {
setNotes((prevNotes) => {
return prevNotes.filter((note, index) => {
return index !== id;
});
});
};
// const handleUpdateNote = (id, updatedNote) => {
// const updatedItem = notes.map((note, index) => {
// return index === id ? updatedNote : note;
// });
// setNotes(updatedItem);
// };
return (
<div>
<CreateArea addNote={addNote} />
{notes.map((note, index) => {
return (
<Note
key={index}
id={index}
title={note.title}
content={note.content}
deleteNote={deleteNote}
//handleUpdateNote={handleUpdateNote}
/>
);
})}
</div>
);
}
There are a couple of mistakes in your code.
The state properties are in the camel case
const [currentNote, setCurrentNote] = useState({
...
editTitle: props.title,
editContent: props.content,
});
But the names of the input are in lowercase.
<input
name='edittitle'
...
/>
<textarea
name='editcontent'
...
/>
Thus in handleInputEdit you don't update the state but add new properties: edittitle and editcontent. Change the names to the camel case.
In React you cant assign to the component prop values, they are read-only.
const updateNote = () => {
...
props.title = currentNote.editTitle;
props.content = currentNote.editContent;
You need to use the handleUpdateNote function passed by the parent component instead. You have it commented for some reason.
<Note
...
//handleUpdateNote={handleUpdateNote}
/>
Check the code below. I think it does what you need.
function Note({ id, title, content, handleUpdateNote, deleteNote }) {
const [editNote, setEditNote] = React.useState(false);
const [currentNote, setCurrentNote] = React.useState({
id,
editTitle: title,
editContent: content,
});
const handleDelete = () => {
deleteNote(id);
};
const handleEdit = () => {
setEditNote(true);
setCurrentNote((prevValue) => ({ ...prevValue }));
};
const handleInputEdit = (event) => {
const { name, value } = event.target;
setCurrentNote((prevValue) => ({
...prevValue,
[name]: value,
}));
};
const updateNote = () => {
handleUpdateNote({
id: currentNote.id,
title: currentNote.editTitle,
content: currentNote.editContent
});
setEditNote(false);
};
return (
<div>
{editNote ? (
<div className='note'>
<input
type='text'
name='editTitle'
defaultValue={currentNote.editTitle}
onChange={handleInputEdit}
className='edit-input'
/>
<textarea
name='editContent'
defaultValue={currentNote.editContent}
row='1'
onChange={handleInputEdit}
className='edit-input'
/>
<button onClick={() => setEditNote(false)}>Cancel</button>
<button onClick={updateNote}>Save</button>
</div>
) : (
<div className='note' onDoubleClick={handleEdit}>
<h1>{title}</h1>
<p>{content}</p>
<button onClick={handleDelete}>DELETE</button>
</div>
)}
</div>
);
}
function CreateArea() {
return null;
}
function Container() {
const [notes, setNotes] = React.useState([
{ title: 'Words', content: 'hello, bye' },
{ title: 'Food', content: 'milk, cheese' }
]);
const addNote = (newNote) => {
setNotes((prevNotes) => {
return [...prevNotes, newNote];
});
};
const deleteNote = (id) => {
setNotes((prevNotes) => {
return prevNotes.filter((note, index) => {
return index !== id;
});
});
};
const handleUpdateNote = ({ id, title, content }) => {
const _notes = [];
for (let i = 0; i < notes.length; i++) {
if (i === id) {
_notes.push({ id, title, content });
} else {
_notes.push(notes[i]);
}
}
setNotes(_notes);
};
return (
<div>
<CreateArea addNote={addNote} />
{notes.map((note, index) => {
return (
<Note
key={index}
id={index}
title={note.title}
content={note.content}
deleteNote={deleteNote}
handleUpdateNote={handleUpdateNote}
/>
);
})}
</div>
);
}
function App() {
return (
<div>
<Container />
</div>
);
}
ReactDOM.render(
<App />,
document.getElementById('root')
);
<script src="https://unpkg.com/react#17/umd/react.development.js" crossorigin></script>
<script src="https://unpkg.com/react-dom#17/umd/react-dom.development.js" crossorigin></script>
<div id="root"></div>
Also, you can store the notes in an object or hash map instead of an array. For example
const [notes, setNotes] = React.useState({
'unique_id': { title: 'Words', content: 'hello, bye' }
});
Then in handleUpdateNote you have
setNotes((prev) => ({ ...prev, unique_id: { title, content } }))
I have a provider that receives data prop, puts it in a state. Also, there are a few methods to manipulate that state.
I pass the state and the data prop to consumers, but every time I change the state, there is no difference between the prop and the state. I want to be able to see what changed so I could update that value.
import { createContext, useContext, useEffect, useState } from "react";
const TableContext = createContext({
data: [],
headings: [],
onChangeCellContent: () => {},
});
const TableProvider = ({ data, headings, children }) => {
const [tableData, setData] = useState(data);
const [tableHeadings, setHeadings] = useState(headings);
useEffect(() => {
setData((previousData) => {
return data.length !== previousData.length ? data : previousData;
});
}, [data]);
const onChangeHeadingCell = ({ key, value }) => {
setHeadings((oldHeadings) =>
oldHeadings.map((heading) => {
if (heading.key === key) {
heading.title = value;
}
return heading;
})
);
};
const onChangeCellContent = ({ rowId, cellKey, value }) => {
setData((previousData) =>
[...previousData].map((row) => {
if (row.id === rowId) {
row[cellKey] = value;
return row;
}
return row;
})
);
};
const onAddNewRow = (rowData) => {
setData((oldData) => [...oldData, rowData]);
};
return (
<TableContext.Provider
value={{
tableData,
data,
onChangeCellContent,
onChangeHeadingCell,
onAddNewRow,
headings: tableHeadings,
}}
>
{children}
</TableContext.Provider>
);
};
export default TableProvider;
export const useTable = () => {
const context = useContext(TableContext);
if (context === "undefined") {
throw Error("Table provider missing");
}
return context;
};
Here is the change handler, it works, but it also changes the original data:
const Row = ({ data: row}) => {
const { onChangeCellContent, headings, data } = useTable();
...
// GIVES ME THE SAME VALUE WHEN I TRIGGER ONCHANGE
console.log(row.value, data.find((s) => s.id === row.id).value);
return <tr><td><select
className="w-full h-full focus:outline-none"
style={{
backgroundColor: "inherit",
}}
value={row.value}
onChange={(e) =>
onChangeCellContent({
rowId: row.id,
cellKey: "value",
value: e.target.value,
})
}
>...</select></td></tr>
I'm new to the react and I would like to know I made a function that makes filtering depending on the boolean values
let [filterState, setFilterSTate] = useState("all");
let filteredUser = todos.filter((е) => {
if (filterState === "active") {
return !е.done;
}
if (filterState === "completed") {
return е.done;
}
return true;
});
in the console, everything is displayed, but I can't figure out how to make it work in the browser itself and only the necessary tricks are displayed
import React, { useState } from "react";
import ReactDOM from "react-dom";
import "./index.css";
const TodoList = () => {
const [newTodo, setNewTodo] = useState("");
const [todos, setTodos] = useState([
{ done: true, text: "Hey", id: 1 },
{ done: false, text: "There", id: 2 },
{ done: false, text: "Dima", id: 3 },
]);
const [id, setId] = useState(4);
const toggleDone = (id) => {
setTodos(
todos.map((todo) => ({
...todo,
done: id === todo.id ? !todo.done : todo.done,
}))
);
};
const updateTodo = (id, e) => {
setTodos(
todos.map((todo) => ({
...todo,
text: id === todo.id ? e.target.value : todo.text,
}))
);
};
const onDelete = (id) => {
setTodos(todos.filter((todo) => todo.id !== id));
};
const updateNewTodo = (e) => {
setNewTodo(e.target.value);
};
const onAdd = () => {
setTodos([
...todos,
{
text: newTodo,
done: false,
id,
},
]);
setId(id + 1);
setNewTodo("");
};
let [filterState, setFilterSTate] = useState("all");
let filteredUser = todos.filter((е) => {
if (filterState === "active") {
return !е.done;
}
if (filterState === "completed") {
return е.done;
}
return true;
});
// let filteredComplited = todos.filter(function (e) {
// return e.done === true;
// });
// console.log("filteredComplited", filteredComplited);
// let filteredActive = todos.filter(function (e) {
// return e.done === false;
// });
// console.log("filteredActive", filteredActive);
// let filteredAll = todos;
// console.log("filteredAll", filteredAll);
return (
<div className="todos">
Todo List
{todos.map((todo) => (
<div key={todo.id} className="todo">
<input
type="checkbox"
value={todo.done}
onChange={() => toggleDone(todo.id)}
/>
<input
type="text"
value={todo.text}
onChange={(evt) => updateTodo(todo.id, evt)}
/>
<button onClick={() => onDelete(todo.id)}>Delete</button>
</div>
))}
<div className="todo">
<input type="text" value={newTodo} onChange={updateNewTodo} />
<button onClick={() => onAdd()}>Add</button>
</div>
<button
onclick={() =>
todos.map((t) => `${t.done ? "x" : ""} ${t.text}`).join("\n")
}
>
Save
</button>
<button onClick={() => setFilterSTate("completed")}>Complited</button>
<button onClick={() => setFilterSTate("active")}>Active</button>
<button onClick={() => setFilterSTate("all")}>All</button>
<pre>filterState: {JSON.stringify(filterState, null, 2)}</pre>
<br />
<pre>{JSON.stringify(filteredUser, null, 2)}</pre>
</div>
);
};
ReactDOM.render(<TodoList />, document.getElementById("todos"));