CODE EXAMPLE FOR TYPESCRIPT

useimperativehandle typescript

type CountdownProps = {}
    
type CountdownHandle = {
  start: () => void,
}
    
const Countdown: React.ForwardRefRenderFunction<CountdownHandle, CountdownProps> = (
  props,
  forwardedRef,
) => {
  React.useImperativeHandle(forwardedRef, ()=>({
    start() {
      alert('Start');
    }
  });

  return <div>Countdown</div>;
}

export default React.forwardRef(Countdown);