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class SystemMenuBlock in Drupal 9

Same name in this branch
  1. 9 core/modules/system/src/Plugin/Derivative/SystemMenuBlock.php \Drupal\system\Plugin\Derivative\SystemMenuBlock
  2. 9 core/modules/system/src/Plugin/Block/SystemMenuBlock.php \Drupal\system\Plugin\Block\SystemMenuBlock
Same name and namespace in other branches
  1. 8 core/modules/system/src/Plugin/Block/SystemMenuBlock.php \Drupal\system\Plugin\Block\SystemMenuBlock
  2. 10 core/modules/system/src/Plugin/Block/SystemMenuBlock.php \Drupal\system\Plugin\Block\SystemMenuBlock

Provides a generic Menu block.

Plugin annotation


@Block(
  id = "system_menu_block",
  admin_label = @Translation("Menu"),
  category = @Translation("Menus"),
  deriver = "Drupal\system\Plugin\Derivative\SystemMenuBlock",
  forms = {
    "settings_tray" = "\Drupal\system\Form\SystemMenuOffCanvasForm",
  },
)

Hierarchy

Expanded class hierarchy of SystemMenuBlock

File

core/modules/system/src/Plugin/Block/SystemMenuBlock.php, line 27

Namespace

Drupal\system\Plugin\Block
View source
class SystemMenuBlock extends BlockBase implements ContainerFactoryPluginInterface {

  /**
   * The menu link tree service.
   *
   * @var \Drupal\Core\Menu\MenuLinkTreeInterface
   */
  protected $menuTree;

  /**
   * The active menu trail service.
   *
   * @var \Drupal\Core\Menu\MenuActiveTrailInterface
   */
  protected $menuActiveTrail;

  /**
   * Constructs a new SystemMenuBlock.
   *
   * @param array $configuration
   *   A configuration array containing information about the plugin instance.
   * @param string $plugin_id
   *   The plugin_id for the plugin instance.
   * @param array $plugin_definition
   *   The plugin implementation definition.
   * @param \Drupal\Core\Menu\MenuLinkTreeInterface $menu_tree
   *   The menu tree service.
   * @param \Drupal\Core\Menu\MenuActiveTrailInterface $menu_active_trail
   *   The active menu trail service.
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, MenuLinkTreeInterface $menu_tree, MenuActiveTrailInterface $menu_active_trail) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->menuTree = $menu_tree;
    $this->menuActiveTrail = $menu_active_trail;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static($configuration, $plugin_id, $plugin_definition, $container
      ->get('menu.link_tree'), $container
      ->get('menu.active_trail'));
  }

  /**
   * {@inheritdoc}
   */
  public function blockForm($form, FormStateInterface $form_state) {
    $config = $this->configuration;
    $defaults = $this
      ->defaultConfiguration();
    $form['menu_levels'] = [
      '#type' => 'details',
      '#title' => $this
        ->t('Menu levels'),
      // Open if not set to defaults.
      '#open' => $defaults['level'] !== $config['level'] || $defaults['depth'] !== $config['depth'],
      '#process' => [
        [
          get_class(),
          'processMenuLevelParents',
        ],
      ],
    ];
    $options = range(0, $this->menuTree
      ->maxDepth());
    unset($options[0]);
    $form['menu_levels']['level'] = [
      '#type' => 'select',
      '#title' => $this
        ->t('Initial visibility level'),
      '#default_value' => $config['level'],
      '#options' => $options,
      '#description' => $this
        ->t('The menu is only visible if the menu link for the current page is at this level or below it. Use level 1 to always display this menu.'),
      '#required' => TRUE,
    ];
    $options[0] = $this
      ->t('Unlimited');
    $form['menu_levels']['depth'] = [
      '#type' => 'select',
      '#title' => $this
        ->t('Number of levels to display'),
      '#default_value' => $config['depth'],
      '#options' => $options,
      '#description' => $this
        ->t('This maximum number includes the initial level.'),
      '#required' => TRUE,
    ];
    $form['menu_levels']['expand_all_items'] = [
      '#type' => 'checkbox',
      '#title' => $this
        ->t('Expand all menu links'),
      '#default_value' => !empty($config['expand_all_items']),
      '#description' => $this
        ->t('Override the option found on each menu link used for expanding children and instead display the whole menu tree as expanded.'),
    ];
    return $form;
  }

  /**
   * Form API callback: Processes the menu_levels field element.
   *
   * Adjusts the #parents of menu_levels to save its children at the top level.
   */
  public static function processMenuLevelParents(&$element, FormStateInterface $form_state, &$complete_form) {
    array_pop($element['#parents']);
    return $element;
  }

  /**
   * {@inheritdoc}
   */
  public function blockSubmit($form, FormStateInterface $form_state) {
    $this->configuration['level'] = $form_state
      ->getValue('level');
    $this->configuration['depth'] = $form_state
      ->getValue('depth');
    $this->configuration['expand_all_items'] = $form_state
      ->getValue('expand_all_items');
  }

  /**
   * {@inheritdoc}
   */
  public function build() {
    $menu_name = $this
      ->getDerivativeId();
    if ($this->configuration['expand_all_items']) {
      $parameters = new MenuTreeParameters();
      $active_trail = $this->menuActiveTrail
        ->getActiveTrailIds($menu_name);
      $parameters
        ->setActiveTrail($active_trail);
    }
    else {
      $parameters = $this->menuTree
        ->getCurrentRouteMenuTreeParameters($menu_name);
    }

    // Adjust the menu tree parameters based on the block's configuration.
    $level = $this->configuration['level'];
    $depth = $this->configuration['depth'];
    $parameters
      ->setMinDepth($level);

    // When the depth is configured to zero, there is no depth limit. When depth
    // is non-zero, it indicates the number of levels that must be displayed.
    // Hence this is a relative depth that we must convert to an actual
    // (absolute) depth, that may never exceed the maximum depth.
    if ($depth > 0) {
      $parameters
        ->setMaxDepth(min($level + $depth - 1, $this->menuTree
        ->maxDepth()));
    }

    // For menu blocks with start level greater than 1, only show menu items
    // from the current active trail. Adjust the root according to the current
    // position in the menu in order to determine if we can show the subtree.
    if ($level > 1) {
      if (count($parameters->activeTrail) >= $level) {

        // Active trail array is child-first. Reverse it, and pull the new menu
        // root based on the parent of the configured start level.
        $menu_trail_ids = array_reverse(array_values($parameters->activeTrail));
        $menu_root = $menu_trail_ids[$level - 1];
        $parameters
          ->setRoot($menu_root)
          ->setMinDepth(1);
        if ($depth > 0) {
          $parameters
            ->setMaxDepth(min($level - 1 + $depth - 1, $this->menuTree
            ->maxDepth()));
        }
      }
      else {
        return [];
      }
    }
    $tree = $this->menuTree
      ->load($menu_name, $parameters);
    $manipulators = [
      [
        'callable' => 'menu.default_tree_manipulators:checkAccess',
      ],
      [
        'callable' => 'menu.default_tree_manipulators:generateIndexAndSort',
      ],
    ];
    $tree = $this->menuTree
      ->transform($tree, $manipulators);
    return $this->menuTree
      ->build($tree);
  }

  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration() {
    return [
      'level' => 1,
      'depth' => 0,
      'expand_all_items' => FALSE,
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function getCacheTags() {

    // Even when the menu block renders to the empty string for a user, we want
    // the cache tag for this menu to be set: whenever the menu is changed, this
    // menu block must also be re-rendered for that user, because maybe a menu
    // link that is accessible for that user has been added.
    $cache_tags = parent::getCacheTags();
    $cache_tags[] = 'config:system.menu.' . $this
      ->getDerivativeId();
    return $cache_tags;
  }

  /**
   * {@inheritdoc}
   */
  public function getCacheContexts() {

    // ::build() uses MenuLinkTreeInterface::getCurrentRouteMenuTreeParameters()
    // to generate menu tree parameters, and those take the active menu trail
    // into account. Therefore, we must vary the rendered menu by the active
    // trail of the rendered menu.
    // Additional cache contexts, e.g. those that determine link text or
    // accessibility of a menu, will be bubbled automatically.
    $menu_name = $this
      ->getDerivativeId();
    return Cache::mergeContexts(parent::getCacheContexts(), [
      'route.menu_active_trails:' . $menu_name,
    ]);
  }

}

Members

Namesort descending Modifiers Type Description Overrides
BlockBase::buildConfigurationForm public function Form constructor. Overrides PluginFormInterface::buildConfigurationForm 2
BlockPluginInterface::BLOCK_LABEL_VISIBLE constant Indicates the block label (title) should be displayed to end users.
BlockPluginTrait::$transliteration protected property The transliteration service.
BlockPluginTrait::access public function
BlockPluginTrait::baseConfigurationDefaults protected function Returns generic default configuration for block plugins.
BlockPluginTrait::blockAccess protected function Indicates whether the block should be shown. 16
BlockPluginTrait::blockValidate public function 3
BlockPluginTrait::buildConfigurationForm public function Creates a generic configuration form for all block types. Individual block plugins can add elements to this form by overriding BlockBase::blockForm(). Most block plugins should not override this method unless they need to alter the generic form elements. Aliased as: traitBuildConfigurationForm
BlockPluginTrait::calculateDependencies public function
BlockPluginTrait::getConfiguration public function 1
BlockPluginTrait::getMachineNameSuggestion public function 1
BlockPluginTrait::getPreviewFallbackString public function 3
BlockPluginTrait::label public function
BlockPluginTrait::setConfiguration public function
BlockPluginTrait::setConfigurationValue public function
BlockPluginTrait::setTransliteration public function Sets the transliteration service.
BlockPluginTrait::submitConfigurationForm public function Most block plugins should not override this method. To add submission handling for a specific block type, override BlockBase::blockSubmit().
BlockPluginTrait::transliteration protected function Wraps the transliteration service.
BlockPluginTrait::validateConfigurationForm public function Most block plugins should not override this method. To add validation for a specific block type, override BlockBase::blockValidate(). 1
ContextAwarePluginAssignmentTrait::addContextAssignmentElement protected function Builds a form element for assigning a context to a given slot.
ContextAwarePluginAssignmentTrait::contextHandler protected function Wraps the context handler.
ContextAwarePluginTrait::$context protected property The data objects representing the context of this plugin.
ContextAwarePluginTrait::$initializedContextConfig protected property Tracks whether the context has been initialized from configuration.
ContextAwarePluginTrait::getCacheMaxAge public function 7
ContextAwarePluginTrait::getContext public function
ContextAwarePluginTrait::getContextDefinition public function
ContextAwarePluginTrait::getContextDefinitions public function
ContextAwarePluginTrait::getContextMapping public function
ContextAwarePluginTrait::getContexts public function
ContextAwarePluginTrait::getContextValue public function
ContextAwarePluginTrait::getContextValues public function
ContextAwarePluginTrait::getPluginDefinition abstract protected function 1
ContextAwarePluginTrait::setContext public function 1
ContextAwarePluginTrait::setContextMapping public function
ContextAwarePluginTrait::setContextValue public function
ContextAwarePluginTrait::validateContexts public function
DependencySerializationTrait::$_entityStorages protected property
DependencySerializationTrait::$_serviceIds protected property
DependencySerializationTrait::__sleep public function 2
DependencySerializationTrait::__wakeup public function 2
MessengerTrait::$messenger protected property The messenger. 27
MessengerTrait::messenger public function Gets the messenger. 27
MessengerTrait::setMessenger public function Sets the messenger.
PluginBase::$configuration protected property Configuration information passed into the plugin. 1
PluginBase::$pluginDefinition protected property The plugin implementation definition. 1
PluginBase::$pluginId protected property The plugin_id.
PluginBase::DERIVATIVE_SEPARATOR constant A string which is used to separate base plugin IDs from the derivative ID.
PluginBase::getBaseId public function Gets the base_plugin_id of the plugin instance. Overrides DerivativeInspectionInterface::getBaseId
PluginBase::getDerivativeId public function Gets the derivative_id of the plugin instance. Overrides DerivativeInspectionInterface::getDerivativeId
PluginBase::getPluginId public function Gets the plugin_id of the plugin instance. Overrides PluginInspectionInterface::getPluginId
PluginBase::isConfigurable public function Determines if the plugin is configurable.
PluginWithFormsTrait::getFormClass public function Implements \Drupal\Core\Plugin\PluginWithFormsInterface::getFormClass().
PluginWithFormsTrait::hasFormClass public function Implements \Drupal\Core\Plugin\PluginWithFormsInterface::hasFormClass().
StringTranslationTrait::$stringTranslation protected property The string translation service. 4
StringTranslationTrait::formatPlural protected function Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals protected function Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation protected function Gets the string translation service.
StringTranslationTrait::setStringTranslation public function Sets the string translation service to use. 2
StringTranslationTrait::t protected function Translates a string to the current language or to a given language.
SystemMenuBlock::$menuActiveTrail protected property The active menu trail service.
SystemMenuBlock::$menuTree protected property The menu link tree service.
SystemMenuBlock::blockForm public function Overrides BlockPluginTrait::blockForm
SystemMenuBlock::blockSubmit public function Overrides BlockPluginTrait::blockSubmit
SystemMenuBlock::build public function Builds and returns the renderable array for this block plugin. Overrides BlockPluginInterface::build
SystemMenuBlock::create public static function Creates an instance of the plugin. Overrides ContainerFactoryPluginInterface::create
SystemMenuBlock::defaultConfiguration public function Overrides BlockPluginTrait::defaultConfiguration
SystemMenuBlock::getCacheContexts public function Overrides ContextAwarePluginTrait::getCacheContexts
SystemMenuBlock::getCacheTags public function Overrides ContextAwarePluginTrait::getCacheTags
SystemMenuBlock::processMenuLevelParents public static function Form API callback: Processes the menu_levels field element.
SystemMenuBlock::__construct public function Constructs a new SystemMenuBlock. Overrides BlockPluginTrait::__construct