ref react functional component code example

Example 1: react focus

const FocusDemo = () => {

    const [inputRef, setInputFocus] = useFocus()

    return (
        <> 
            <button onClick={setInputFocus} >
               FOCUS
            </button>
            <input ref={inputRef} />
        </>
    )

}

const useFocus = () => {
    const htmlElRef = useRef(null)
    const setFocus = () => {htmlElRef.current &&  htmlElRef.current.focus()}

    return [ htmlElRef, setFocus ] 
}

Example 2: cre&atRefs react js

const node = this.myRef.current;

Example 3: ref in functional components

function MyFunctionComponent() {  return <input />;
}

class Parent extends React.Component {
  constructor(props) {
    super(props);
    this.textInput = React.createRef();  }
  render() {
    // This will *not* work!
    return (
      <MyFunctionComponent ref={this.textInput} />    );
  }
}

Example 4: ref in functional components

function CustomTextInput(props) {
  // textInput must be declared here so the ref can refer to it  const textInput = useRef(null);  
  function handleClick() {
    textInput.current.focus();  }

  return (
    <div>
      <input
        type="text"
        ref={textInput} />      <input
        type="button"
        value="Focus the text input"
        onClick={handleClick}
      />
    </div>
  );
}