25 lines
783 B
JavaScript
25 lines
783 B
JavaScript
import { useEffect, useLayoutEffect, useRef } from 'react';
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/**
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* Returns ref that is `true` on the initial render and `false` on subsequent renders. It
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* is StrictMode safe, so will reset correctly if the component is unmounted and remounted.
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*
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* This hook *must* be used before any effects that read it's value to be accurate.
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*/
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export default function useIsInitialRenderRef() {
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const effectCount = useRef(0);
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const isInitialRenderRef = useRef(true);
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useLayoutEffect(() => {
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effectCount.current += 1;
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if (effectCount.current >= 2) {
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isInitialRenderRef.current = false;
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}
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});
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// Strict mode handling in React 18
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useEffect(() => () => {
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effectCount.current = 0;
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isInitialRenderRef.current = true;
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}, []);
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return isInitialRenderRef;
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} |