import { useEffect, useRef } from 'react'; // via: https://overreacted.io/making-setinterval-declarative-with-react-hooks/ export default function useInterval(callback, delay) { const savedCallback = useRef(); // Remember the latest callback. useEffect(() => { savedCallback.current = callback; }, [callback]); // Set up the interval. useEffect(() => { function tick() { savedCallback.current(); } if (delay !== null) { let id = setInterval(tick, delay); return () => clearInterval(id); } }, [delay]); }