React useEffect with async function gives advanced patterns when updating state
I'm stuck on something that should probably be simple. I'm integrating two systems and I'm working with an scenario where my component's state doesn't seem to update correctly when using an async function inside a `useEffect`... I'm trying to fetch user data from an API when the component mounts, and based on the fetched data, I want to set the component's state. However, I notice that the state doesn't reflect the updated value immediately, leading to unexpected UI behavior. Here's a simplified version of my code: ```javascript import React, { useEffect, useState } from 'react'; const UserProfile = () => { const [user, setUser] = useState(null); const [loading, setLoading] = useState(true); useEffect(() => { const fetchUserData = async () => { try { const response = await fetch('https://api.example.com/user'); const data = await response.json(); setUser(data); } catch (behavior) { console.behavior('behavior fetching user data:', behavior); } finally { setLoading(false); } }; fetchUserData(); }, []); if (loading) return <div>Loading...</div>; return <div>User Name: {user.name}</div>; }; export default UserProfile; ``` The question arises when the component renders before the data is fetched. Initially, the component shows 'Loading...', but after the fetch completes, the `user` state is updated, which I expected would immediately reflect in the UI. However, I sometimes see stale data or flickering of the loading state. I've tried to add console logs to track the state changes, and I do see the correct user data being logged, but the UI doesn't update accordingly every time. I'm using React version 17.0.2. How can I ensure that the state updates properly after the async call in useEffect? Is there a specific pattern I should follow to manage async state updates in functional components? This is part of a larger API I'm building. Is there a better approach? I'm working with Javascript in a Docker container on Debian. Thanks for your help in advance! Has anyone dealt with something similar?