This commit is contained in:
2026-05-28 19:16:14 +03:00
parent a520406547
commit 8cc72afd7b
+24 -10
View File
@@ -1,21 +1,32 @@
import React, { useMemo, useCallback, useState } from 'react' import React, { useMemo, useCallback, useState } from 'react'
const Button = React.memo(({ onClick }) => { const TodoItem = React.memo(({ item, onToggle, onDelete }) => {
console.log('Button rendred'); console.log(`rendred ${item.id}`);
return <button onClick={onClick}>Click me</button> return <li>
{item.name}
<button onClick={() => onToggle(item.id)}>Done</button>
<button onClick={() => onDelete(item.id)}>remove</button>
</li>
}) })
function Parent() { function ItemList({ items }) {
const [count,setCount] = useState(0);
const handlerClick = useCallback(()=>{ const handleToggle = useCallback(id => {
setCount(prev => prev + 1); items.done = true;
console.log(`Item ${id} done`)
console.log(id)
},[]); },[]);
const handleDelete = useCallback(id => {
items.pop(id);
},[]);
return ( return (
<> <>
<h3>Counter: {count}</h3> <h3>List items</h3>
<Button onClick={handlerClick} /> {items.map(item => (
<TodoItem key={item.id} item={item}
onToggle={handleToggle} onDelete={handleDelete} />
))}
</> </>
) )
} }
@@ -25,7 +36,10 @@ function App() {
<> <>
{/* Добавьте тестовый контент для проверки */} {/* Добавьте тестовый контент для проверки */}
<h1>Hello, React!</h1> <h1>Hello, React!</h1>
<Parent /> <ItemList items={[
{id:1,name:'Первый',done:false},
{id:2,name:'Второй',done:false}
]} />
</> </>
) )
} }