Wrap a function in useState

Question

" Wrap getListViewSetting in a function for useState ", what does this mean?

 const [isListView, setIsListView] = useState(
    getListViewSetting(location?.pathname?.replace('/', ''), true),
  );

Does this answer your question? [What is useState() in React?](https://stackoverflow.com/questions/53165945/what-is-usestate-in-react) — Joel, Apr 15 '21 at 21:37

score 1 · Accepted Answer · answered Apr 15 '21 at 21:37

Whoever (or whatever tool) said this probably meant for you to do:

const [isListView, setIsListView] = useState(
  () => getListViewSetting(location?.pathname?.replace('/', ''), true)
);

If you pass a function into useState, then react will call that function exactly once to determine the initial value. If getListViewSetting is expensive, that can be a performance improvement, because the code you had will need to call it on every render, even though the value is useless other than on the first render.

Wrap a function in useState

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