React useRef Hook Not Updating on Fetch Response in Concurrent Mode
I'm trying to debug I'm having trouble with This might be a silly question, but I tried several approaches but none seem to work..... I'm facing an issue where I'm using the `useRef` hook to store a reference to some data fetched from an API, but it seems like the reference isn't updating as I expect when running in React's Concurrent Mode. I've set up an async function to fetch data on component mount, and I want to store the result in a ref for later access without causing a re-render. However, when I log the value of the ref after the fetch, it still holds the initial state. Here’s a simplified version of my code: ```javascript import React, { useEffect, useRef } from 'react'; const MyComponent = () => { const dataRef = useRef(null); useEffect(() => { const fetchData = async () => { const response = await fetch('https://api.example.com/data'); const data = await response.json(); dataRef.current = data; // Updates the ref console.log('Fetched data:', dataRef.current); }; fetchData(); }, []); const handleClick = () => { console.log('Data from ref:', dataRef.current); // This is always null on first click }; return <button onClick={handleClick}>Log Data</button>; }; export default MyComponent; ``` I’ve checked that the API call is successful and returns data, but the `console.log` in the `handleClick` function always logs `null` during the first click, and only shows the fetched data upon subsequent clicks. I've also tried using `useState` instead of `useRef`, but I want to avoid re-renders for performance reasons since I’m just reading this data later. Is there a way to ensure that the value in `dataRef` is actually updated before I log it in the `handleClick` function? I'm using React 18.0.0 and am unsure if this behavior is related to the new Concurrent Mode features. Am I missing something obvious? I'm working on a web app that needs to handle this. This is part of a larger service I'm building. Cheers for any assistance! I recently upgraded to Javascript LTS. Has anyone dealt with something similar?