Tristan Yang
33 lines
750 B
TypeScript
33 lines
750 B
TypeScript
import { useRef, useEffect } from "react";
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export default function useInView<T extends HTMLElement>() {
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const ref = useRef<T>(null);
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const observer = new IntersectionObserver(
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(entries) => {
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entries.forEach((entry) => {
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const intersecting = entry.isIntersecting;
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const currEle = entry.target;
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if (intersecting) {
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currEle.classList.add("in_view");
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} else {
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currEle.classList.remove("in_view");
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}
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});
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},
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{ threshold: 0 }
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);
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useEffect(() => {
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const currEle = ref.current;
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if (currEle) {
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observer.observe(ref.current);
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}
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return () => {
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if (currEle) {
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observer.unobserve(currEle);
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}
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};
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}, [ref]);
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return ref;
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}
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