class Toolbar

class Toolbar extends RenderElement {
    
    /**
     * {@inheritdoc}
     */
    public function getInfo() {
        $class = get_class($this);
        return [
            '#pre_render' => [
                [
                    $class,
                    'preRenderToolbar',
                ],
            ],
            '#theme' => 'toolbar',
            '#attached' => [
                'library' => [
                    'toolbar/toolbar',
                ],
            ],
            // Metadata for the toolbar wrapping element.
'#attributes' => [
                // The id cannot be simply "toolbar" or it will clash with the
                // simpletest tests listing which produces a checkbox with attribute
                // id="toolbar".
'id' => 'toolbar-administration',
                'role' => 'group',
                'aria-label' => $this->t('Site administration toolbar'),
            ],
            // Metadata for the administration bar.
'#bar' => [
                '#heading' => $this->t('Toolbar items'),
                '#attributes' => [
                    'id' => 'toolbar-bar',
                    'role' => 'navigation',
                    'aria-label' => $this->t('Toolbar items'),
                ],
            ],
        ];
    }
    
    /**
     * Builds the Toolbar as a structured array ready for drupal_render().
     *
     * Since building the toolbar takes some time, it is done just prior to
     * rendering to ensure that it is built only if it will be displayed.
     *
     * @param array $element
     *   A renderable array.
     *
     * @return array
     *   A renderable array.
     *
     * @see toolbar_page_top()
     */
    public static function preRenderToolbar($element) {
        // Get the configured breakpoints to switch from vertical to horizontal
        // toolbar presentation.
        $breakpoints = static::breakpointManager()->getBreakpointsByGroup('toolbar');
        if (!empty($breakpoints)) {
            $media_queries = [];
            foreach ($breakpoints as $id => $breakpoint) {
                $media_queries[$id] = $breakpoint->getMediaQuery();
            }
            $element['#attached']['drupalSettings']['toolbar']['breakpoints'] = $media_queries;
        }
        $module_handler = static::moduleHandler();
        // Get toolbar items from all modules that implement hook_toolbar().
        $items = $module_handler->invokeAll('toolbar');
        // Allow for altering of hook_toolbar().
        $module_handler->alter('toolbar', $items);
        // Sort the children.
        uasort($items, [
            '\\Drupal\\Component\\Utility\\SortArray',
            'sortByWeightProperty',
        ]);
        // Merge in the original toolbar values.
        $element = array_merge($element, $items);
        // Assign each item a unique ID, based on its key.
        foreach (Element::children($element) as $key) {
            $element[$key]['#id'] = Html::getId('toolbar-item-' . $key);
        }
        return $element;
    }
    
    /**
     * Wraps the breakpoint manager.
     *
     * @return \Drupal\breakpoint\BreakpointManagerInterface
     */
    protected static function breakpointManager() {
        return \Drupal::service('breakpoint.manager');
    }
    
    /**
     * Wraps the module handler.
     *
     * @return \Drupal\Core\Extension\ModuleHandlerInterface
     */
    protected static function moduleHandler() {
        return \Drupal::moduleHandler();
    }

}