How can one use one Webform element's selection as the argument in an Entity Select element using Views

So my colleague, @nikathone, provided the following code, to be put in a .module file. Replace the MYMODULE and MY_WEBFORM_ID according to your needs:

<?php use Drupal\Core\Form\FormStateInterface; use Drupal\webform\Element\WebformEntitySelect; /** * Implements hook_webform_submission_form_alter(). */ function MYMODULE_webform_submission_form_alter(array &$form, FormStateInterface $form_state, $form_id) { $webform_id = $form['#webform_id'] ?? ''; if ($webform_id !== 'MY_WEBFORM_ID') { return; } $organization_element = $form['elements']['organization'] ?? []; $site_element = $form['elements']['site'] ?? []; if (!$organization_element || !$site_element || empty($site_element['#selection_settings']['view'])) { return; } // Settings ajax related properties. $site_element_wrapper_id = $site_element['#webform_id'] . '--wrapper'; $organization_element['#ajax'] = [ 'callback' => 'MYMODULE_webform_submission_form_organization_element_ajax_callback', 'wrapper' => $site_element_wrapper_id, ]; $site_element['#prefix'] = '<div id="' . $site_element_wrapper_id . '">'; $site_element['#suffix'] = '</div>'; // Attempting to retrieve possible selected organization. if (!($selected_organization = $form_state->getValue('organization'))) { $selected_organization = $organization_element['#default_value'] ?? 0; } // Apply the selected organization if a selected one was found. if ($selected_organization) { $site_element['#selection_settings']['view']['arguments'] = [$selected_organization]; // Reset the options so that we can repopulate it again. Without this the // ::setOptions method above won't process the new arguments. $site_element['#options'] = []; $form_object = $form_state->getFormObject(); $settings = ['webform_submission' => $form_object->getEntity()]; WebformEntitySelect::setOptions($site_element, $settings); } $form['elements']['organization'] = $organization_element; $form['elements']['site'] = $site_element; } /** * Ajax callback for the site element. * * @param array $form * The full form element. * @param \Drupal\Core\Form\FormStateInterface $form_state * The form state. * * @return array * The site element array. */ function MYMODULE_webform_submission_form_organization_element_ajax_callback(array $form, FormStateInterface $form_state) { return $form['elements']['site']; }