excalidraw/src/hooks/useScrollPosition.ts
Arnost Pleskot 1e3c94a37a
feat: recover scrolled position after Library re-opening (#6624)
Co-authored-by: dwelle <luzar.david@gmail.com>
2023-05-31 10:22:02 +02:00

33 lines
807 B
TypeScript

import { useEffect } from "react";
import { atom, useAtom } from "jotai";
import throttle from "lodash.throttle";
const scrollPositionAtom = atom<number>(0);
export const useScrollPosition = <T extends HTMLElement>(
elementRef: React.RefObject<T>,
) => {
const [scrollPosition, setScrollPosition] = useAtom(scrollPositionAtom);
useEffect(() => {
const { current: element } = elementRef;
if (!element) {
return;
}
const handleScroll = throttle(() => {
const { scrollTop } = element;
setScrollPosition(scrollTop);
}, 200);
element.addEventListener("scroll", handleScroll);
return () => {
handleScroll.cancel();
element.removeEventListener("scroll", handleScroll);
};
}, [elementRef, setScrollPosition]);
return scrollPosition;
};