[TS] ref 타입 지정하기 (object is possibly null)

error: Object is possibly 'null'
에러가 떠서, 해당 값이 있을 경우의 조건을 추가해주었다.

function Sidebar({ isSideBarOpened }: TSideBar) {
  const sideBarRef = useRef<HTMLInputElement>(null);
  useEffect(() => {
    if (isSideBarOpened && sideBarRef.current) {
      sideBarRef.current.style.transform = 'translateX(30px)';
    } else {
      //
    }
  }, [isSideBarOpened]);

Reference

• ref 타입은 어떻게 지정해주어야 하는지
  https://driip.me/7126d5d5-1937-44a8-98ed-f9065a7c35b5

https://darrengwon.tistory.com/865

• 에러: Object is possibly null
  https://www.designcise.com/web/tutorial/how-to-fix-object-is-possibly-null-typescript-error-when-using-useref-react-hook

• https://kyounghwan01.github.io/blog/TS/object-null/#%E1%84%90%E1%85%A1%E1%84%8B%E1%85%B5%E1%86%B8-%E1%84%83%E1%85%A1%E1%86%AB%E1%84%8B%E1%85%A5%E1%86%AB-%E1%84%89%E1%85%A1%E1%84%8B%E1%85%AD%E1%86%BC-type-assertion