useInterval.js

function useInterval(callback, delay) {
  const intervalRef = React.useRef(null);
  const savedCallback = React.useRef(callback);
  React.useEffect(() => {
    savedCallback.current = callback;
  });
  React.useEffect(() => {
    const tick = () => savedCallback.current();
    if (typeof delay === 'number') {
      intervalRef.current = window.setInterval(tick, delay);
      return () => window.clearInterval(intervalRef.current);
    }
  }, [delay]);
  return intervalRef;
}