const useInterval = (callback, delay) => {
const savedCallback = useRef();
// 保存新回调
useEffect(() => {
savedCallback.current = callback;
});
// 建立 interval
useEffect(() => {
function tick() {
savedCallback.current();
}
if (delay !== null) {
let id = setInterval(tick, delay);
return () => clearInterval(id);
}
}, [delay]);
}