@shopify/polaris/build/esm/utilities/focus-manager/hooks.js

Shopify’s admin product component library

import { useContext, useId, useMemo, useEffect } from 'react';
import { MissingAppProviderError } from '../errors.js';
import { FocusManagerContext } from './context.js';

function useFocusManager({
  trapping
}) {
  const focusManager = useContext(FocusManagerContext);
  const id = useId();
  if (!focusManager) {
    throw new MissingAppProviderError('No FocusManager was provided.');
  }
  const {
    trapFocusList,
    add: addFocusItem,
    remove: removeFocusItem
  } = focusManager;
  const canSafelyFocus = trapFocusList[0] === id;
  const value = useMemo(() => ({
    canSafelyFocus
  }), [canSafelyFocus]);
  useEffect(() => {
    if (!trapping) return;
    addFocusItem(id);
    return () => {
      removeFocusItem(id);
    };
  }, [addFocusItem, id, removeFocusItem, trapping]);
  return value;
}

export { useFocusManager };