File size: 674 Bytes
1e92f2d | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 | import { RefObject, useEffect, useMemo, useState } from 'react';
export default function useIsVisible(
ref: RefObject< HTMLElement >,
options?: IntersectionObserverInit
) {
const [ isIntersecting, setIntersecting ] = useState< boolean | undefined >( undefined );
const observer = useMemo( () => {
if ( typeof window === 'undefined' ) {
return;
}
return new IntersectionObserver(
( [ entry ] ) => setIntersecting( entry.isIntersecting ),
options
);
}, [ options ] );
useEffect( () => {
if ( ref && ref.current ) {
observer?.observe( ref.current );
}
return () => observer?.disconnect();
}, [ observer, ref ] );
return isIntersecting;
}
|