function book_form_update in Drupal 9

Same name and namespace in other branches

1. 8 core/modules/book/book.module \book_form_update()
2. 6 modules/book/book.pages.inc \book_form_update()
3. 7 modules/book/book.module \book_form_update()

Renders a new parent page select element when the book selection changes.

This function is called via Ajax when the selected book is changed on a node or book outline form.

Return value

The rendered parent page select element.

1 string reference to 'book_form_update'

BookManager::addFormElements in core/modules/book/src/BookManager.php

Builds the common elements of the book form for the node and outline forms.

File

core/modules/book/book.module, line 208

Allows users to create and organize related content in an outline.

Code

function book_form_update($form, FormStateInterface $form_state) {
  return $form['book']['pid'];
}