diff core/lib/Drupal/Core/Menu/menu.api.php @ 0:4c8ae668cc8c

Initial import (non-working)

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/lib/Drupal/Core/Menu/menu.api.php	Wed Nov 29 16:09:58 2017 +0000
@@ -0,0 +1,485 @@
+<?php
+
+/**
+ * @file
+ * Hooks and documentation related to the menu system and links.
+ */
+
+/**
+ * @defgroup menu Menu system
+ * @{
+ * Define the navigation menus, local actions and tasks, and contextual links.
+ *
+ * @section sec_overview Overview and terminology
+ * The menu system uses routes; see the
+ * @link routing Routing API topic @endlink for more information. It is used
+ * for navigation menus, local tasks, local actions, and contextual links:
+ * - Navigation menus are hierarchies of menu links; links point to routes or
+ *   URLs.
+ * - Menu links and their hierarchies can be defined by Drupal subsystems
+ *   and modules, or created in the user interface using the Menu UI module.
+ * - Local tasks are groups of related routes. Local tasks are usually rendered
+ *   as a group of tabs.
+ * - Local actions are used for operations such as adding a new item on a page
+ *   that lists items of some type. Local actions are usually rendered as
+ *   buttons.
+ * - Contextual links are actions that are related to sections of rendered
+ *   output, and are usually rendered as a pop-up list of links. The
+ *   Contextual Links module handles the gathering and rendering of contextual
+ *   links.
+ *
+ * The following sections of this topic provide an overview of the menu API.
+ * For more detailed information, see
+ * https://www.drupal.org/developing/api/8/menu
+ *
+ * @section sec_links Defining menu links for the administrative menu
+ * Routes for administrative tasks can be added to the main Drupal
+ * administrative menu hierarchy. To do this, add lines like the following to a
+ * module_name.links.menu.yml file (in the top-level directory for your module):
+ * @code
+ * dblog.overview:
+ *   title: 'Recent log messages'
+ *   parent: system.admin_reports
+ *   description: 'View events that have recently been logged.'
+ *   route_name: dblog.overview
+ *   weight: -1
+ * @endcode
+ * Some notes:
+ * - The first line is the machine name for your menu link, which usually
+ *   matches the machine name of the route (given in the 'route_name' line).
+ * - parent: The machine name of the menu link that is the parent in the
+ *   administrative hierarchy. See system.links.menu.yml to find the main
+ *   skeleton of the hierarchy.
+ * - weight: Lower (negative) numbers come before higher (positive) numbers,
+ *   for menu items with the same parent.
+ *
+ * Discovered menu links from other modules can be altered using
+ * hook_menu_links_discovered_alter().
+ *
+ * @todo Derivatives will probably be defined for these; when they are, add
+ *   documentation here.
+ *
+ * @section sec_tasks Defining groups of local tasks (tabs)
+ * Local tasks appear as tabs on a page when there are at least two defined for
+ * a route, including the base route as the main tab, and additional routes as
+ * other tabs. Static local tasks can be defined by adding lines like the
+ * following to a module_name.links.task.yml file (in the top-level directory
+ * for your module):
+ * @code
+ * book.admin:
+ *   route_name: book.admin
+ *   title: 'List'
+ *   base_route: book.admin
+ * book.settings:
+ *   route_name: book.settings
+ *   title: 'Settings'
+ *   base_route: book.admin
+ *   weight: 100
+ * @endcode
+ * Some notes:
+ * - The first line is the machine name for your local task, which usually
+ *   matches the machine name of the route (given in the 'route_name' line).
+ * - base_route: The machine name of the main task (tab) for the set of local
+ *   tasks.
+ * - weight: Lower (negative) numbers come before higher (positive) numbers,
+ *   for tasks on the same base route. If there is a tab whose route
+ *   matches the base route, that will be the default/first tab shown.
+ *
+ * Local tasks from other modules can be altered using
+ * hook_menu_local_tasks_alter().
+ *
+ * @todo Derivatives are in flux for these; when they are more stable, add
+ *   documentation here.
+ *
+ * @section sec_actions Defining local actions for routes
+ * Local actions can be defined for operations related to a given route. For
+ * instance, adding content is a common operation for the content management
+ * page, so it should be a local action. Static local actions can be
+ * defined by adding lines like the following to a
+ * module_name.links.action.yml file (in the top-level directory for your
+ * module):
+ * @code
+ * node.add_page:
+ *   route_name: node.add_page
+ *   title: 'Add content'
+ *   appears_on:
+ *     - system.admin_content
+ * @endcode
+ * Some notes:
+ * - The first line is the machine name for your local action, which usually
+ *   matches the machine name of the route (given in the 'route_name' line).
+ * - appears_on: Machine names of one or more routes that this local task
+ *   should appear on.
+ *
+ * Local actions from other modules can be altered using
+ * hook_menu_local_actions_alter().
+ *
+ * @todo Derivatives are in flux for these; when they are more stable, add
+ *   documentation here.
+ *
+ * @section sec_contextual Defining contextual links
+ * Contextual links are displayed by the Contextual Links module for user
+ * interface elements whose render arrays have a '#contextual_links' element
+ * defined. For example, a block render array might look like this, in part:
+ * @code
+ * array(
+ *   '#contextual_links' => array(
+ *     'block' => array(
+ *       'route_parameters' => array('block' => $entity->id()),
+ *     ),
+ *   ),
+ * @endcode
+ * In this array, the outer key 'block' defines a "group" for contextual
+ * links, and the inner array provides values for the route's placeholder
+ * parameters (see @ref sec_placeholders above).
+ *
+ * To declare that a defined route should be a contextual link for a
+ * contextual links group, put lines like the following in a
+ * module_name.links.contextual.yml file (in the top-level directory for your
+ * module):
+ * @code
+ * block_configure:
+ *   title: 'Configure block'
+ *   route_name: 'entity.block.edit_form'
+ *   group: 'block'
+ * @endcode
+ * Some notes:
+ * - The first line is the machine name for your contextual link, which usually
+ *   matches the machine name of the route (given in the 'route_name' line).
+ * - group: This needs to match the link group defined in the render array.
+ *
+ * Contextual links from other modules can be altered using
+ * hook_contextual_links_alter().
+ *
+ * @todo Derivatives are in flux for these; when they are more stable, add
+ *   documentation here.
+ *
+ * @section sec_rendering Rendering menus
+ * Once you have created menus (that contain menu links), you want to render
+ * them. Drupal provides a block (Drupal\system\Plugin\Block\SystemMenuBlock) to
+ * do so.
+ *
+ * However, perhaps you have more advanced needs and you're not satisfied with
+ * what the menu blocks offer you. If that's the case, you'll want to:
+ * - Instantiate \Drupal\Core\Menu\MenuTreeParameters, and set its values to
+ *   match your needs. Alternatively, you can use
+ *   MenuLinkTree::getCurrentRouteMenuTreeParameters() to get a typical
+ *   default set of parameters, and then customize them to suit your needs.
+ * - Call \Drupal\Core\MenuLinkTree::load() with your menu link tree parameters,
+ *   this will return a menu link tree.
+ * - Pass the menu tree to \Drupal\Core\Menu\MenuLinkTree::transform() to apply
+ *   menu link tree manipulators that transform the tree. You will almost always
+ *   want to apply access checking. The manipulators that you will typically
+ *   need can be found in \Drupal\Core\Menu\DefaultMenuLinkTreeManipulators.
+ * - Potentially write a custom menu tree manipulator, see
+ *   \Drupal\Core\Menu\DefaultMenuLinkTreeManipulators for examples. This is
+ *   only necessary if you want to do things like adding extra metadata to
+ *   rendered links to display icons next to them.
+ * - Pass the menu tree to \Drupal\Core\Menu\MenuLinkTree::build(), this will
+ *   build a renderable array.
+ *
+ * Combined, that would look like this:
+ * @code
+ * $menu_tree = \Drupal::menuTree();
+ * $menu_name = 'my_menu';
+ *
+ * // Build the typical default set of menu tree parameters.
+ * $parameters = $menu_tree->getCurrentRouteMenuTreeParameters($menu_name);
+ *
+ * // Load the tree based on this set of parameters.
+ * $tree = $menu_tree->load($menu_name, $parameters);
+ *
+ * // Transform the tree using the manipulators you want.
+ * $manipulators = array(
+ *   // Only show links that are accessible for the current user.
+ *   array('callable' => 'menu.default_tree_manipulators:checkAccess'),
+ *   // Use the default sorting of menu links.
+ *   array('callable' => 'menu.default_tree_manipulators:generateIndexAndSort'),
+ * );
+ * $tree = $menu_tree->transform($tree, $manipulators);
+ *
+ * // Finally, build a renderable array from the transformed tree.
+ * $menu = $menu_tree->build($tree);
+ *
+ * $menu_html = drupal_render($menu);
+ * @endcode
+ *
+ * @}
+ */
+
+/**
+ * @addtogroup hooks
+ * @{
+ */
+
+/**
+ * Alters all the menu links discovered by the menu link plugin manager.
+ *
+ * @param array $links
+ *   The link definitions to be altered.
+ *
+ * @return array
+ *   An array of discovered menu links. Each link has a key that is the machine
+ *   name, which must be unique. By default, use the route name as the
+ *   machine name. In cases where multiple links use the same route name, such
+ *   as two links to the same page in different menus, or two links using the
+ *   same route name but different route parameters, the suggested machine name
+ *   patten is the route name followed by a dot and a unique suffix. For
+ *   example, an additional logout link might have a machine name of
+ *   user.logout.navigation, and default links provided to edit the article and
+ *   page content types could use machine names
+ *   entity.node_type.edit_form.article and entity.node_type.edit_form.page.
+ *   Since the machine name may be arbitrary, you should never write code that
+ *   assumes it is identical to the route name.
+ *
+ *   The value corresponding to each machine name key is an associative array
+ *   that may contain the following key-value pairs:
+ *   - title: (required) The title of the menu link. If this should be
+ *     translated, create a \Drupal\Core\StringTranslation\TranslatableMarkup
+ *     object.
+ *   - description: The description of the link. If this should be
+ *     translated, create a \Drupal\Core\StringTranslation\TranslatableMarkup
+ *     object.
+ *   - route_name: (optional) The route name to be used to build the path.
+ *     Either the route_name or url element must be provided.
+ *   - route_parameters: (optional) The route parameters to build the path.
+ *   - url: (optional) If you have an external link use this element instead of
+ *     providing route_name.
+ *   - parent: (optional) The machine name of the link that is this link's menu
+ *     parent.
+ *   - weight: (optional) An integer that determines the relative position of
+ *     items in the menu; higher-weighted items sink. Defaults to 0. Menu items
+ *     with the same weight are ordered alphabetically.
+ *   - menu_name: (optional) The machine name of a menu to put the link in, if
+ *     not the default Tools menu.
+ *   - expanded: (optional) If set to TRUE, and if a menu link is provided for
+ *     this menu item (as a result of other properties), then the menu link is
+ *     always expanded, equivalent to its 'always expanded' checkbox being set
+ *     in the UI.
+ *   - options: (optional) An array of options to be passed to
+ *     \Drupal\Core\Utility\LinkGeneratorInterface::generate() when generating
+ *     a link from this menu item.
+ *
+ * @ingroup menu
+ */
+function hook_menu_links_discovered_alter(&$links) {
+  // Change the weight and title of the user.logout link.
+  $links['user.logout']['weight'] = -10;
+  $links['user.logout']['title'] = new \Drupal\Core\StringTranslation\TranslatableMarkup('Logout');
+  // Conditionally add an additional link with a title that's not translated.
+  if (\Drupal::moduleHandler()->moduleExists('search')) {
+    $links['menu.api.search'] = [
+      'title' => \Drupal::config('system.site')->get('name'),
+      'route_name' => 'menu.api.search',
+      'description' => new \Drupal\Core\StringTranslation\TranslatableMarkup('View popular search phrases for this site.'),
+      'parent' => 'system.admin_reports',
+    ];
+  }
+}
+
+/**
+ * Alter local tasks displayed on the page before they are rendered.
+ *
+ * This hook is invoked by \Drupal\Core\Menu\LocalTaskManager::getLocalTasks().
+ * The system-determined tabs and actions are passed in by reference. Additional
+ * tabs may be added.
+ *
+ * The local tasks are under the 'tabs' element and keyed by plugin ID.
+ *
+ * Each local task is an associative array containing:
+ * - #theme: The theme function to use to render.
+ * - #link: An associative array containing:
+ *   - title: The localized title of the link.
+ *   - url: a Url object.
+ *   - localized_options: An array of options to pass to
+ *     \Drupal\Core\Utility\LinkGeneratorInterface::generate().
+ * - #weight: The link's weight compared to other links.
+ * - #active: Whether the link should be marked as 'active'.
+ *
+ * @param array $data
+ *   An associative array containing list of (up to 2) tab levels that contain a
+ *   list of tabs keyed by their href, each one being an associative array
+ *   as described above.
+ * @param string $route_name
+ *   The route name of the page.
+ *
+ * @ingroup menu
+ */
+function hook_menu_local_tasks_alter(&$data, $route_name) {
+
+  // Add a tab linking to node/add to all pages.
+  $data['tabs'][0]['node.add_page'] = [
+      '#theme' => 'menu_local_task',
+      '#link' => [
+          'title' => t('Example tab'),
+          'url' => Url::fromRoute('node.add_page'),
+          'localized_options' => [
+              'attributes' => [
+                  'title' => t('Add content'),
+              ],
+          ],
+      ],
+  ];
+}
+
+/**
+ * Alter local actions plugins.
+ *
+ * @param array $local_actions
+ *   The array of local action plugin definitions, keyed by plugin ID.
+ *
+ * @see \Drupal\Core\Menu\LocalActionInterface
+ * @see \Drupal\Core\Menu\LocalActionManager
+ *
+ * @ingroup menu
+ */
+function hook_menu_local_actions_alter(&$local_actions) {
+}
+
+/**
+ * Alter local tasks plugins.
+ *
+ * @param array $local_tasks
+ *   The array of local tasks plugin definitions, keyed by plugin ID.
+ *
+ * @see \Drupal\Core\Menu\LocalTaskInterface
+ * @see \Drupal\Core\Menu\LocalTaskManager
+ *
+ * @ingroup menu
+ */
+function hook_local_tasks_alter(&$local_tasks) {
+  // Remove a specified local task plugin.
+  unset($local_tasks['example_plugin_id']);
+}
+
+/**
+ * Alter contextual links before they are rendered.
+ *
+ * This hook is invoked by
+ * \Drupal\Core\Menu\ContextualLinkManager::getContextualLinkPluginsByGroup().
+ * The system-determined contextual links are passed in by reference. Additional
+ * links may be added and existing links can be altered.
+ *
+ * Each contextual link contains the following entries:
+ * - title: The localized title of the link.
+ * - route_name: The route name of the link.
+ * - route_parameters: The route parameters of the link.
+ * - localized_options: An array of URL options.
+ * - (optional) weight: The weight of the link, which is used to sort the links.
+ *
+ *
+ * @param array $links
+ *   An associative array containing contextual links for the given $group,
+ *   as described above. The array keys are used to build CSS class names for
+ *   contextual links and must therefore be unique for each set of contextual
+ *   links.
+ * @param string $group
+ *   The group of contextual links being rendered.
+ * @param array $route_parameters
+ *   The route parameters passed to each route_name of the contextual links.
+ *   For example:
+ *   @code
+ *   array('node' => $node->id())
+ *   @endcode
+ *
+ * @see \Drupal\Core\Menu\ContextualLinkManager
+ *
+ * @ingroup menu
+ */
+function hook_contextual_links_alter(array &$links, $group, array $route_parameters) {
+  if ($group == 'menu') {
+    // Dynamically use the menu name for the title of the menu_edit contextual
+    // link.
+    $menu = \Drupal::entityManager()->getStorage('menu')->load($route_parameters['menu']);
+    $links['menu_edit']['title'] = t('Edit menu: @label', ['@label' => $menu->label()]);
+  }
+}
+
+/**
+ * Alter the plugin definition of contextual links.
+ *
+ * @param array $contextual_links
+ *   An array of contextual_links plugin definitions, keyed by contextual link
+ *   ID. Each entry contains the following keys:
+ *     - title: The displayed title of the link
+ *     - route_name: The route_name of the contextual link to be displayed
+ *     - group: The group under which the contextual links should be added to.
+ *       Possible values are e.g. 'node' or 'menu'.
+ *
+ * @see \Drupal\Core\Menu\ContextualLinkManager
+ *
+ * @ingroup menu
+ */
+function hook_contextual_links_plugins_alter(array &$contextual_links) {
+  $contextual_links['menu_edit']['title'] = 'Edit the menu';
+}
+
+/**
+ * Perform alterations to the breadcrumb built by the BreadcrumbManager.
+ *
+ * @param \Drupal\Core\Breadcrumb\Breadcrumb $breadcrumb
+ *   A breadcrumb object returned by BreadcrumbBuilderInterface::build().
+ * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
+ *   The current route match.
+ * @param array $context
+ *   May include the following key:
+ *   - builder: the instance of
+ *     \Drupal\Core\Breadcrumb\BreadcrumbBuilderInterface that constructed this
+ *     breadcrumb, or NULL if no builder acted based on the current attributes.
+ *
+ * @ingroup menu
+ */
+function hook_system_breadcrumb_alter(\Drupal\Core\Breadcrumb\Breadcrumb &$breadcrumb, \Drupal\Core\Routing\RouteMatchInterface $route_match, array $context) {
+  // Add an item to the end of the breadcrumb.
+  $breadcrumb->addLink(\Drupal\Core\Link::createFromRoute(t('Text'), 'example_route_name'));
+}
+
+/**
+ * Alter the parameters for links.
+ *
+ * @param array $variables
+ *   An associative array of variables defining a link. The link may be either a
+ *   "route link" using \Drupal\Core\Utility\LinkGenerator::link(), which is
+ *   exposed as the 'link_generator' service or a link generated by
+ *   \Drupal\Core\Utility\LinkGeneratorInterface::generate(). If the link is a
+ *   "route link", 'route_name' will be set; otherwise, 'path' will be set.
+ *   The following keys can be altered:
+ *   - text: The link text for the anchor tag. If the hook implementation
+ *     changes this text it needs to preserve the safeness of the original text.
+ *     Using t() or \Drupal\Component\Utility\SafeMarkup::format() with
+ *     @placeholder is recommended as this will escape the original text if
+ *     necessary. If the resulting text is not marked safe it will be escaped.
+ *   - url_is_active: Whether or not the link points to the currently active
+ *     URL.
+ *   - url: The \Drupal\Core\Url object.
+ *   - options: An associative array of additional options that will be passed
+ *     to either \Drupal\Core\Utility\UnroutedUrlAssembler::assemble() or
+ *     \Drupal\Core\Routing\UrlGenerator::generateFromRoute() to generate the
+ *     href attribute for this link, and also used when generating the link.
+ *     Defaults to an empty array. It may contain the following elements:
+ *     - 'query': An array of query key/value-pairs (without any URL-encoding) to
+ *       append to the URL.
+ *     - absolute: Whether to force the output to be an absolute link (beginning
+ *       with http:). Useful for links that will be displayed outside the site,
+ *       such as in an RSS feed. Defaults to FALSE.
+ *     - language: An optional language object. May affect the rendering of
+ *       the anchor tag, such as by adding a language prefix to the path.
+ *     - attributes: An associative array of HTML attributes to apply to the
+ *       anchor tag. If element 'class' is included, it must be an array; 'title'
+ *       must be a string; other elements are more flexible, as they just need
+ *       to work as an argument for the constructor of the class
+ *       Drupal\Core\Template\Attribute($options['attributes']).
+ *
+ * @see \Drupal\Core\Utility\UnroutedUrlAssembler::assemble()
+ * @see \Drupal\Core\Routing\UrlGenerator::generateFromRoute()
+ */
+function hook_link_alter(&$variables) {
+  // Add a warning to the end of route links to the admin section.
+  if (isset($variables['route_name']) && strpos($variables['route_name'], 'admin') !== FALSE) {
+    $variables['text'] = t('@text (Warning!)', ['@text' => $variables['text']]);
+  }
+}
+
+/**
+ * @} End of "addtogroup hooks".
+ */