contextual.module in Drupal 9
Same filename and directory in other branches
Adds contextual links to perform actions related to elements on a page.
File
core/modules/contextual/contextual.moduleView source
<?php
/**
* @file
* Adds contextual links to perform actions related to elements on a page.
*/
use Drupal\Core\Url;
use Drupal\Component\Serialization\Json;
use Drupal\Component\Utility\UrlHelper;
use Drupal\Core\Language\LanguageInterface;
use Drupal\Core\Routing\RouteMatchInterface;
/**
* Implements hook_toolbar().
*/
function contextual_toolbar() {
$items = [];
$items['contextual'] = [
'#cache' => [
'contexts' => [
'user.permissions',
],
],
];
if (!\Drupal::currentUser()
->hasPermission('access contextual links')) {
return $items;
}
$items['contextual'] += [
'#type' => 'toolbar_item',
'tab' => [
'#type' => 'html_tag',
'#tag' => 'button',
'#value' => t('Edit'),
'#attributes' => [
'class' => [
'toolbar-icon',
'toolbar-icon-edit',
],
'aria-pressed' => 'false',
'type' => 'button',
],
],
'#wrapper_attributes' => [
'class' => [
'hidden',
'contextual-toolbar-tab',
],
],
'#attached' => [
'library' => [
'contextual/drupal.contextual-toolbar',
],
],
];
return $items;
}
/**
* Implements hook_page_attachments().
*
* Adds the drupal.contextual-links library to the page for any user who has the
* 'access contextual links' permission.
*
* @see contextual_preprocess()
*/
function contextual_page_attachments(array &$page) {
if (!\Drupal::currentUser()
->hasPermission('access contextual links')) {
return;
}
$page['#attached']['library'][] = 'contextual/drupal.contextual-links';
}
/**
* Implements hook_help().
*/
function contextual_help($route_name, RouteMatchInterface $route_match) {
switch ($route_name) {
case 'help.page.contextual':
$output = '';
$output .= '<h3>' . t('About') . '</h3>';
$output .= '<p>' . t('The Contextual links module gives users with the <em>Use contextual links</em> permission quick access to tasks associated with certain areas of pages on your site. For example, a menu displayed as a block has links to edit the menu and configure the block. For more information, see the <a href=":contextual">online documentation for the Contextual Links module</a>.', [
':contextual' => 'https://www.drupal.org/documentation/modules/contextual',
]) . '</p>';
$output .= '<h3>' . t('Uses') . '</h3>';
$output .= '<dl>';
$output .= '<dt>' . t('Displaying contextual links') . '</dt>';
$output .= '<dd>';
$output .= t('Contextual links for an area on a page are displayed using a contextual links button. There are two ways to make the contextual links button visible:');
$output .= '<ol>';
$sample_picture = [
'#theme' => 'image',
'#uri' => 'core/misc/icons/bebebe/pencil.svg',
'#alt' => t('contextual links button'),
];
$sample_picture = \Drupal::service('renderer')
->render($sample_picture);
$output .= '<li>' . t('Hovering over the area of interest will temporarily make the contextual links button visible (which looks like a pencil in most themes, and is normally displayed in the upper right corner of the area). The icon typically looks like this: @picture', [
'@picture' => $sample_picture,
]) . '</li>';
$output .= '<li>' . t('If you have the <a href=":toolbar">Toolbar module</a> enabled, clicking the contextual links button in the toolbar (which looks like a pencil) will make all contextual links buttons on the page visible. Clicking this button again will toggle them to invisible.', [
':toolbar' => \Drupal::moduleHandler()
->moduleExists('toolbar') ? Url::fromRoute('help.page', [
'name' => 'toolbar',
])
->toString() : '#',
]) . '</li>';
$output .= '</ol>';
$output .= t('Once the contextual links button for the area of interest is visible, click the button to display the links.');
$output .= '</dd>';
$output .= '</dl>';
return $output;
}
}
/**
* Implements hook_preprocess().
*
* @see contextual_pre_render_placeholder()
* @see contextual_page_attachments()
* @see \Drupal\contextual\ContextualController::render()
*/
function contextual_preprocess(&$variables, $hook, $info) {
$variables['#cache']['contexts'][] = 'user.permissions';
if (!\Drupal::currentUser()
->hasPermission('access contextual links')) {
return;
}
// Determine the primary theme function argument.
if (!empty($info['variables'])) {
$keys = array_keys($info['variables']);
$key = $keys[0];
}
elseif (!empty($info['render element'])) {
$key = $info['render element'];
}
if (!empty($key) && isset($variables[$key])) {
$element = $variables[$key];
}
if (isset($element) && is_array($element) && !empty($element['#contextual_links'])) {
// Mark this element as potentially having contextual links attached to it.
$variables['attributes']['class'][] = 'contextual-region';
// Renders a contextual links placeholder unconditionally, thus not breaking
// the render cache. Although the empty placeholder is rendered for all
// users, contextual_page_attachments() only adds the asset library for
// users with the 'access contextual links' permission, thus preventing
// unnecessary HTTP requests for users without that permission.
$variables['title_suffix']['contextual_links'] = [
'#type' => 'contextual_links_placeholder',
'#id' => _contextual_links_to_id($element['#contextual_links']),
];
}
}
/**
* Implements hook_contextual_links_view_alter().
*
* @see \Drupal\contextual\Plugin\views\field\ContextualLinks::render()
*/
function contextual_contextual_links_view_alter(&$element, $items) {
if (isset($element['#contextual_links']['contextual'])) {
$encoded_links = $element['#contextual_links']['contextual']['metadata']['contextual-views-field-links'];
$element['#links'] = Json::decode(rawurldecode($encoded_links));
}
}
/**
* Serializes #contextual_links property value array to a string.
*
* Examples:
* - node:node=1:langcode=en
* - views_ui_edit:view=frontpage:location=page&view_name=frontpage&view_display_id=page_1&langcode=en
* - menu:menu=tools:langcode=en|block:block=bartik.tools:langcode=en
*
* So, expressed in a pattern:
* <group>:<route parameters>:<metadata>
*
* The route parameters and options are encoded as query strings.
*
* @param array $contextual_links
* The $element['#contextual_links'] value for some render element.
*
* @return string
* A serialized representation of a #contextual_links property value array for
* use in a data- attribute.
*/
function _contextual_links_to_id($contextual_links) {
$ids = [];
$langcode = \Drupal::languageManager()
->getCurrentLanguage(LanguageInterface::TYPE_URL)
->getId();
foreach ($contextual_links as $group => $args) {
$route_parameters = UrlHelper::buildQuery($args['route_parameters']);
$args += [
'metadata' => [],
];
// Add the current URL language to metadata so a different ID will be
// computed when URLs vary by language. This allows to store different
// language-aware contextual links on the client side.
$args['metadata'] += [
'langcode' => $langcode,
];
$metadata = UrlHelper::buildQuery($args['metadata']);
$ids[] = "{$group}:{$route_parameters}:{$metadata}";
}
return implode('|', $ids);
}
/**
* Unserializes the result of _contextual_links_to_id().
*
* Note that $id is user input. Before calling this method the ID should be
* checked against the token stored in the 'data-contextual-token' attribute
* which is passed via the 'tokens' request parameter to
* \Drupal\contextual\ContextualController::render().
*
* @param string $id
* A serialized representation of a #contextual_links property value array.
*
* @return array
* The value for a #contextual_links property.
*
* @see _contextual_links_to_id()
* @see \Drupal\contextual\ContextualController::render()
*/
function _contextual_id_to_links($id) {
$contextual_links = [];
$contexts = explode('|', $id);
foreach ($contexts as $context) {
list($group, $route_parameters_raw, $metadata_raw) = explode(':', $context);
parse_str($route_parameters_raw, $route_parameters);
$metadata = [];
parse_str($metadata_raw, $metadata);
$contextual_links[$group] = [
'route_parameters' => $route_parameters,
'metadata' => $metadata,
];
}
return $contextual_links;
}
Functions
Name | Description |
---|---|
contextual_contextual_links_view_alter | Implements hook_contextual_links_view_alter(). |
contextual_help | Implements hook_help(). |
contextual_page_attachments | Implements hook_page_attachments(). |
contextual_preprocess | Implements hook_preprocess(). |
contextual_toolbar | Implements hook_toolbar(). |
_contextual_id_to_links | Unserializes the result of _contextual_links_to_id(). |
_contextual_links_to_id | Serializes #contextual_links property value array to a string. |