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<?php
namespace Drupal\system\Plugin\Block;
use Drupal\Core\Block\BlockBase;
use Drupal\Core\Cache\Cache;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Menu\MenuActiveTrailInterface;
use Drupal\Core\Menu\MenuLinkTreeInterface;
use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;
class SystemMenuBlock extends BlockBase implements ContainerFactoryPluginInterface {
protected $menuTree;
protected $menuActiveTrail;
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;
}
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'), $container
->get('menu.active_trail'));
}
public function blockForm($form, FormStateInterface $form_state) {
$config = $this->configuration;
$defaults = $this
->defaultConfiguration();
$form['menu_levels'] = array(
'#type' => 'details',
'#title' => $this
->t('Menu levels'),
'#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'] = array(
'#type' => 'select',
'#title' => $this
->t('Initial menu level'),
'#default_value' => $config['level'],
'#options' => $options,
'#description' => $this
->t('The menu will only be visible if the menu item for the current page is at or below the selected starting level. Select level 1 to always keep this menu visible.'),
'#required' => TRUE,
);
$options[0] = $this
->t('Unlimited');
$form['menu_levels']['depth'] = array(
'#type' => 'select',
'#title' => $this
->t('Maximum number of menu levels to display'),
'#default_value' => $config['depth'],
'#options' => $options,
'#description' => $this
->t('The maximum number of menu levels to show, starting from the initial menu level. For example: with an initial level 2 and a maximum number of 3, menu levels 2, 3 and 4 can be displayed.'),
'#required' => TRUE,
);
return $form;
}
public static function processMenuLevelParents(&$element, FormStateInterface $form_state, &$complete_form) {
array_pop($element['#parents']);
return $element;
}
public function blockSubmit($form, FormStateInterface $form_state) {
$this->configuration['level'] = $form_state
->getValue('level');
$this->configuration['depth'] = $form_state
->getValue('depth');
}
public function build() {
$menu_name = $this
->getDerivativeId();
$parameters = $this->menuTree
->getCurrentRouteMenuTreeParameters($menu_name);
$level = $this->configuration['level'];
$depth = $this->configuration['depth'];
$parameters
->setMinDepth($level);
if ($depth > 0) {
$parameters
->setMaxDepth(min($level + $depth - 1, $this->menuTree
->maxDepth()));
}
$tree = $this->menuTree
->load($menu_name, $parameters);
$manipulators = array(
array(
'callable' => 'menu.default_tree_manipulators:checkAccess',
),
array(
'callable' => 'menu.default_tree_manipulators:generateIndexAndSort',
),
);
$tree = $this->menuTree
->transform($tree, $manipulators);
return $this->menuTree
->build($tree);
}
public function defaultConfiguration() {
return [
'level' => 1,
'depth' => 0,
];
}
public function getCacheTags() {
$cache_tags = parent::getCacheTags();
$cache_tags[] = 'config:system.menu.' . $this
->getDerivativeId();
return $cache_tags;
}
public function getCacheContexts() {
$menu_name = $this
->getDerivativeId();
return Cache::mergeContexts(parent::getCacheContexts(), [
'route.menu_active_trails:' . $menu_name,
]);
}
}