started to implement blabla : menu block, link vuejsed, route, component

web/themes/custom/materiotheme/templates/menu/menu--header.html.twig

@@ -0,0 +1,58 @@
+{#
+/**
+ * @file
+ * Theme override to display a menu.
+ *
+ * Available variables:
+ * - menu_name: The machine name of the menu.
+ * - items: A nested list of menu items. Each menu item contains:
+ *   - attributes: HTML attributes for the menu item.
+ *   - below: The menu item child items.
+ *   - title: The menu link title.
+ *   - url: The menu link url, instance of \Drupal\Core\Url
+ *   - localized_options: Menu link localized options.
+ *   - is_expanded: TRUE if the link has visible children within the current
+ *     menu tree.
+ *   - is_collapsed: TRUE if the link has children within the current menu tree
+ *     that are not currently visible.
+ *   - in_active_trail: TRUE if the link is in the active trail.
+ */
+#}
+{% import _self as menus %}
+
+{#
+  We call a macro which calls itself to render the full tree.
+  @see https://twig.symfony.com/doc/1.x/tags/macro.html
+#}
+{{ menus.menu_links(items, attributes, 0) }}
+
+{% macro menu_links(items, attributes, menu_level) %}
+  {% import _self as menus %}
+  {% if items %}
+    {% if menu_level == 0 %}
+      <ul{{ attributes.addClass('menu') }}>
+    {% else %}
+      <ul class="menu">
+    {% endif %}
+    {% for item in items %}
+      {%
+        set classes = [
+          'menu-item',
+          item.is_expanded ? 'menu-item--expanded',
+          item.is_collapsed ? 'menu-item--collapsed',
+          item.in_active_trail ? 'menu-item--active-trail',
+        ]
+      %}
+      <li{{ item.attributes.addClass(classes) }}>
+        {# this does not work because of the '@' #}
+        {# we have to do it via js | not working neither #}
+        {#{{ link(item.title, item.url, {'@click.prevent':['onclick']}) }}#}
+        <a href="{{ item.url }}" @click.prevent='onclick'>{{ item.title }}</a>
+        {% if item.below %}
+          {{ menus.menu_links(item.below, attributes, menu_level + 1) }}
+        {% endif %}
+      </li>
+    {% endfor %}
+    </ul>
+  {% endif %}
+{% endmacro %}