drupal/core/modules/edit/edit.module

<?php

/**
 * @file
 * Provides in-place content editing functionality for fields.
 *
 * The Edit module makes content editable in-place. Rather than having to visit
 * a separate page to edit content, it may be edited in-place.
 *
 * Technically, this module adds classes and data- attributes to fields and
 * entities, enabling them for in-place editing.
 */

use Drupal\Core\Entity\EntityInterface;
use Drupal\edit\Form\EditFieldForm;
use Drupal\Component\Utility\NestedArray;

/**
 * Implements hook_custom_theme().
 *
 * @todo Add an event subscriber to the Ajax system to automatically set the
 *   base page theme for all Ajax requests, and then remove this one off.
 */
function edit_custom_theme() {
  if (substr(current_path(), 0, 5) === 'edit/') {
    return ajax_base_page_theme();
  }
}

/**
 * Implements hook_permission().
 */
function edit_permission() {
  return array(
    'access in-place editing' => array(
      'title' => t('Access in-place editing'),
    ),
  );
}

/**
 * Implements hook_toolbar().
 */
function edit_toolbar() {
  if (!user_access('access in-place editing')) {
    return;
  }

  $tab['edit'] = array(
    'tab' => array(
      'title' => t('Edit'),
      'href' => '',
      'html' => FALSE,
      'attributes' => array(
        'class' => array('icon', 'icon-edit', 'edit-nothing-editable-hidden'),
      ),
    ),
    'tray' => array(
      '#attached' => array(
        'library' => array(
          array('edit', 'edit'),
        ),
      ),
    ),
  );

  // Include the attachments and settings for all available editors.
  $attachments = drupal_container()->get('edit.editor.selector')->getAllEditorAttachments();
  $tab['edit']['tray']['#attached'] = NestedArray::mergeDeep($tab['edit']['tray']['#attached'], $attachments);

  return $tab;
}

/**
 * Implements hook_library().
 */
function edit_library_info() {
  $path = drupal_get_path('module', 'edit');
  $options = array(
    'scope' => 'footer',
    'attributes' => array('defer' => TRUE),
  );
  $libraries['edit'] = array(
    'title' => 'Edit: in-place editing',
    'website' => 'http://drupal.org/project/edit',
    'version' => VERSION,
    'js' => array(
      // Core.
      $path . '/js/edit.js' => $options,
      $path . '/js/app.js' => $options,
      // Routers.
      $path . '/js/routers/edit-router.js' => $options,
      // Models.
      $path . '/js/models/edit-app-model.js' => $options,
      // Views.
      $path . '/js/views/propertyeditordecoration-view.js' => $options,
      $path . '/js/views/menu-view.js' => $options,
      $path . '/js/views/modal-view.js' => $options,
      $path . '/js/views/overlay-view.js' => $options,
      $path . '/js/views/toolbar-view.js' => $options,
      // Backbone.sync implementation on top of Drupal forms.
      $path . '/js/backbone.drupalform.js' => $options,
      // VIE service.
      $path . '/js/viejs/EditService.js' => $options,
      // Create.js subclasses.
      $path . '/js/createjs/editable.js' => $options,
      $path . '/js/createjs/storage.js' => $options,
      // Other.
      $path . '/js/util.js' => $options,
      $path . '/js/theme.js' => $options,
      // Basic settings.
      array(
        'data' => array('edit' => array(
          'metadataURL' => url('edit/metadata'),
          'fieldFormURL' => url('edit/form/!entity_type/!id/!field_name/!langcode/!view_mode'),
          'rerenderProcessedTextURL' => url('edit/text/!entity_type/!id/!field_name/!langcode/!view_mode'),
          'context' => 'body',
        )),
        'type' => 'setting',
      ),
    ),
    'css' => array(
      $path . '/css/edit.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'jquery'),
      array('system', 'underscore'),
      array('system', 'backbone'),
      array('system', 'vie.core'),
      array('system', 'create.editonly'),
      array('system', 'jquery.form'),
      array('system', 'drupal.form'),
      array('system', 'drupal.ajax'),
      array('system', 'drupalSettings'),
    ),
  );
  $libraries['edit.editor.form'] = array(
    'title' => '"Form" Create.js PropertyEditor widget',
    'version' => VERSION,
    'js' => array(
      $path . '/js/createjs/editingWidgets/formwidget.js' => $options,
    ),
    'dependencies' => array(
      array('edit', 'edit'),
    ),
  );
  $libraries['edit.editor.direct'] = array(
    'title' => '"Direct" Create.js PropertyEditor widget',
    'version' => VERSION,
    'js' => array(
      $path . '/js/createjs/editingWidgets/drupalcontenteditablewidget.js' => $options,
    ),
    'dependencies' => array(
      array('edit', 'edit'),
    ),
  );

  return $libraries;
}

/**
 * Implements hook_preprocess_HOOK() for field.tpl.php.
 */
function edit_preprocess_field(&$variables) {
  $element = $variables['element'];
  $entity = $element['#object'];
  $variables['attributes']['data-edit-id'] = $entity->entityType() . '/' . $entity->id() . '/' . $element['#field_name'] . '/' . $element['#language'] . '/' . $element['#view_mode'];
}

/**
 * Form constructor for the field editing form.
 *
 * @ingroup forms
 */
function edit_field_form(array $form, array &$form_state, EntityInterface $entity, $field_name) {
  $form_handler = new EditFieldForm();
  return $form_handler->build($form, $form_state, $entity, $field_name);
}