React 18: Issue with Updating Component State based on Parent State Change with useEffect Dependency Array
Could someone explain Can someone help me understand I'm facing an issue where a child component needs to update its state whenever a parent component's state changes, but the updates aren't happening as expected. I'm using React 18 and the `useEffect` hook to manage this. Here's a simplified version of my components: ```javascript import React, { useState, useEffect } from 'react'; const ParentComponent = () => { const [parentValue, setParentValue] = useState(0); const incrementValue = () => { setParentValue(prev => prev + 1); }; return ( <div> <button onClick={incrementValue}>Increment Parent Value</button> <ChildComponent parentValue={parentValue} /> </div> ); }; const ChildComponent = ({ parentValue }) => { const [childValue, setChildValue] = useState(0); useEffect(() => { setChildValue(parentValue * 2); }, [parentValue]); // Dependency on parentValue return <div>Child Value: {childValue}</div>; }; export default ParentComponent; ``` The expectation is that the `childValue` should update to double the `parentValue` whenever it changes. However, I'm encountering a subtle issue where, after multiple increments, the `childValue` doesn't seem to reflect the correct doubled value. Sometimes it shows outdated values. When I inspect the `parentValue`, it updates correctly in the parent component, but the child component appears to lag behind, especially when I click the button rapidly. I've ensured that I've correctly set up the dependency array in the `useEffect`, but I still see this lag. Is there something I'm missing here? Could it be related to how React batches state updates? I'm currently using React 18.0.0. Any help would be appreciated! For reference, this is a production CLI tool. Could someone point me to the right documentation?