👀 Views: 0 💬 Answers: 1 📅 Created: 2025-06-13

reactjs css useState JavaScript

I'm wondering if anyone has experience with I need some guidance on I'm struggling with dynamically applying class names based on component state in my React 18 application. I have a button that toggles a loading state, and I want to change its class name conditionally based on whether loading is true or false. Currently, I'm using the `useState` hook to manage the loading state, but I'm not seeing the expected style changes in my component. Here’s a simplified version of my code: ```jsx import React, { useState } from 'react'; const MyButton = () => { const [loading, setLoading] = useState(false); const handleClick = () => { setLoading(true); // Simulate an API call setTimeout(() => { setLoading(false); }, 2000); }; return ( <button className={loading ? 'btn-loading' : 'btn-default'} onClick={handleClick} > {loading ? 'Loading...' : 'Click Me'} </button> ); }; export default MyButton; ``` I’ve defined the classes in my CSS like this: ```css .btn-default { background-color: blue; color: white; } .btn-loading { background-color: gray; color: darkgray; cursor: not-allowed; } ``` The button correctly displays 'Loading...' when clicked, but I noticed that the class doesn't change immediately—sometimes it takes a second or two to reflect the new class. I suspected it might have to do with how React batches state updates, but I’m not sure how to resolve this. I’ve also tried using `useEffect` to log the loading state but didn’t find any issues with the state changes. Any suggestions on how I can ensure the class name updates instantly upon state change? Also, are there any best practices for handling such loading states effectively, especially for better performance? Any ideas what could be causing this? Am I missing something obvious? This is happening in both development and production on CentOS. Thanks in advance!