In React, when you define a callback function and pass it as a prop to a child component, the callback will maintain the reference to the original props from the first render where it was defined. This behavior is known as "closing over" the props.

This means that even if the props of the parent component change and trigger a re-render, the callback function will still have access to the original props from the first render when it is called. This behavior is expected because the callback function captures the lexical environment (including the props) in which it was defined.

To ensure that the callback receives the updated props when it is called, you can use the useCallback hook provided by React. The useCallback hook allows you to specify dependencies and memoize the callback function so that it only updates when those dependencies change.

Here's an example of how you can use the useCallback hook to solve the issue:

import React, { useCallback, useState } from 'react'; function ParentComponent() { const [count, setCount] = useState(0); const handleCallback = useCallback(() => { // Callback function logic here, using the updated props console.log(count); }, [count]); return ( <div> <ChildComponent callback={handleCallback} /> <button onClick={() => setCount(count + 1)}>Increment</button> </div> ); } function ChildComponent({ callback }) { // Call the callback function when needed callback(); return <div>Child Component</div>; }

In the example above, the handleCallback function is wrapped in the useCallback hook and has the count variable as a dependency. This ensures that the callback function is memoized and updates whenever count changes. Therefore, when the callback() is called inside the ChildComponent, it will have access to the updated value of count.

By using the useCallback hook and specifying the necessary dependencies, you can ensure that the callback function receives the updated props when it is called.

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