React 18: implementing Suspense and Concurrent Features in Lazy-loaded Components
I'm learning this framework and I recently switched to I'm working with a scenario with React 18 when trying to implement Suspense in conjunction with lazy-loaded components. I created a simple application where I am using `React.lazy()` to load a component that fetches data asynchronously. However, I'm noticing that when the component is loaded, it sometimes renders without showing the fallback UI, leading to a flash of content. Here’s a simplified version of my code: ```javascript import React, { Suspense, useState, useEffect } from 'react'; const LazyComponent = React.lazy(() => import('./LazyComponent')); const App = () => { const [data, setData] = useState(null); useEffect(() => { const fetchData = async () => { const response = await fetch('https://api.example.com/data'); const result = await response.json(); setData(result); }; fetchData(); }, []); return ( <div> <h1>My App</h1> <Suspense fallback={<div>Loading...</div>}> {data ? <LazyComponent data={data} /> : <div>Loading data...</div>} </Suspense> </div> ); }; export default App; ``` The scenario occurs when the `LazyComponent` is loaded right after the data is fetched. The fallback UI doesn’t render for the `LazyComponent`, leading to the component being displayed immediately, which is not the intended behavior. I have also tried wrapping the lazy-loaded component in another `Suspense` block and adjusting the loading states, but that didn’t help either. I’m running React 18.0.0 and React Router v6.0.0. The console does not show any behavior messages; it just seems like the rendering order is not behaving as expected. I would appreciate any insights on how to ensure that the fallback UI is consistently shown until the `LazyComponent` has fully loaded. I'm working on a mobile app that needs to handle this. Any feedback is welcome!