How to prevent flickering of the interface caused by useEffect?

Interface flickering due to useEffect often occurs when the state updates after the initial render, causing a re-render with new data.

To prevent flickering:

• Initialize the state with the necessary values immediately, so there is no empty or default state that changes later.
• Use conditional rendering, showing a loading indicator or placeholder until the data is ready.
• In some cases, you can use useLayoutEffect instead of useEffect — it runs synchronously after all DOM mutations, reducing visible changes.
• Cache data to avoid reloading it on every render.

Example:

const [data, setData] = useState(null);

useEffect(() => {
  fetchData().then(response => setData(response));
}, []);

return (
  <div>
    {data ? <Content data={data} /> : <LoadingSpinner />}
  </div>
);

Here, while data is loading, a spinner is shown, preventing flickering of empty content.