👀 Views: 595 💬 Answers: 1 📅 Created: 2025-08-07

react react-spring performance javascript

I've been banging my head against this for hours. I'm facing performance issues when using React Spring for animations in my React application. I have a component that renders a list of items, each with animated entry/exit transitions. The problem occurs when the state of the component updates, causing frame drops and janky animations. The animations are defined using the `useSpring` hook, which works perfectly when the state isn't changing. However, when I add or remove items from the list, I notice significant lag. Here's a simplified version of my component: ```javascript import React, { useState } from 'react'; import { useSpring, animated } from 'react-spring'; const AnimatedList = () => { const [items, setItems] = useState(['Item 1', 'Item 2', 'Item 3']); const handleAddItem = () => { setItems(prev => [...prev, `Item ${prev.length + 1}`]); }; const handleRemoveItem = (index) => { setItems(prev => prev.filter((_, i) => i !== index)); }; return ( <div> <button onClick={handleAddItem}>Add Item</button> <ul> {items.map((item, index) => { const props = useSpring({ opacity: 1, from: { opacity: 0 }}); return ( <animated.li key={index} style={props} onClick={() => handleRemoveItem(index)}> {item} </animated.li> ); })} </ul> </div> ); }; export default AnimatedList; ``` In my setup, I noticed that the `useSpring` hook for each item creates an animation whenever the state updates. This leads to frame drops, especially noticeable in browsers like Chrome when I have a long list of items. I've tried memoizing the list items using `React.memo`, but it hasn't made much of a difference. I also considered batching state updates using `unstable_batchedUpdates`, but I’m not sure it would help in this case. Is there a better way to handle animations in a performant manner with React Spring, especially when working with lists and frequent state updates? Any insights on optimizing this would be greatly appreciated. How would you solve this?