import { RefObject, useEffect } from 'react'; export function useOnClickOutside(ref: RefObject, handler: (e: MouseEvent) => void) { useEffect( () => { const listener = (event: MouseEvent) => { // Do nothing if clicking ref's element or descendent elements if (!ref.current || ref.current.contains(event.target)) { return; } handler(event); }; document.addEventListener('mousedown', listener); document.addEventListener('touchstart', listener); return () => { document.removeEventListener('mousedown', listener); document.removeEventListener('touchstart', listener); }; }, // Add ref and handler to effect dependencies // It's worth noting that because passed in handler is a new ... // ... function on every render that will cause this effect ... // ... callback/cleanup to run every render. It's not a big deal ... // ... but to optimize you can wrap handler in useCallback before ... // ... passing it into this hook. [ref, handler], ); }