NextJs / Framer Motion：使用 useViewportScroll 时我收到此警告：警告：useLayoutEffect 在服务器上不执行任何操作，

Question

I am using NextJs with Framer Motion. Everything is working properly but I got this warning:

Warning: useLayoutEffect does nothing on the server, because its effect cannot be encoded into the server renderer's output format. This will lead to a mismatch between the initial, non-hydrated UI and the intended UI. To avoid this, useLayoutEffect should only be used in components that render exclusively on the client.

Answer 1

Seems like this will be get fixed in the upcoming framer-motion version.

From the GitHub conversation

The React 18 upgrade in #1438 introduced a new useIsMounted hook, that that didn't use the useIsomorphicLayoutEffect. This resulted in a warning rendered serverside. Fix by replacing useLayoutEffect with useIsomprohicLayoutEffect

https://github.com/framer/motion/pull/1452

For a temporary fix, you can cancel rendering the the component if it is not client render, by adding such as

const [isLoaded, setLoaded] = useState(false);
useEffect(() => {
  setLoaded(true);
}, []);

if (!isLoaded) {
  return null;
}

return (
  ...your component
);

Answer 2

Next does SSR which is why its throwing this warning as useLayoutEffect doesn't run on server.

Official docs of useLayoutEffect :

The signature is identical to useEffect, but it fires synchronously after all DOM mutations. Use this to read layout from the DOM and synchronously re-render. Updates scheduled inside useLayoutEffect will be flushed synchronously, before the browser has a chance to paint.