jsx2.tsx

// Parts copied from:
// https://github.com/typescript-cheatsheets/react-typescript-cheatsheet/tree/bd3e2a6c213932fbf0cec6befea4fb90457714ab
// License: MIT.

function TextInputWithFocusButton() {
  // initialise with null, but tell TypeScript we are looking for an HTMLInputElement
  const inputEl = React.useRef<HTMLInputElement>(null);
  const onButtonClick = () => {
    // strict null checks need us to check if inputEl and current exist.
    // but once current exists, it is of type HTMLInputElement, thus it
    // has the method focus! ✅
    if (inputEl && inputEl.current) {
      inputEl.current.focus();
    }
  };
  return (
    <>
      {/* in addition, inputEl only can be used with input elements. Yay! */}
      <input ref={inputEl} type="text" />
      <button onClick={onButtonClick}>Focus the input</button>
    </>
  );
}

type ButtonProps = React.ComponentProps<typeof Button>; // no problem! grab your own!
type AlertButtonProps = Omit<ButtonProps, "onClick">; // modify
const AlertButton: React.FC<AlertButtonProps> = (props) => (
  <Button onClick={() => alert("hello")} {...props} />
);