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

Shopify’s product component library

import { useContext, useMemo, useEffect } from 'react';
import { MissingAppProviderError } from '../errors.js';
import { FocusManagerContext } from './context.js';
import { useUniqueId } from '../unique-id/hooks.js';

function useFocusManager() {
  var focusManager = useContext(FocusManagerContext);
  var id = useUniqueId();

  if (!focusManager) {
    throw new MissingAppProviderError('No FocusManager was provided.');
  }

  var {
    trapFocusList,
    add: addFocusItem,
    remove: removeFocusItem
  } = focusManager;
  var canSafelyFocus = trapFocusList[0] === id;
  var value = useMemo(() => ({
    canSafelyFocus
  }), [canSafelyFocus]);
  useEffect(() => {
    addFocusItem(id);
    return () => {
      removeFocusItem(id);
    };
  }, [addFocusItem, id, removeFocusItem]);
  return value;
}

export { useFocusManager };