mkdocs-material/src/partials/nav-item.html

<!--
  Copyright (c) 2016-2021 Martin Donath <martin.donath@squidfunk.com>

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to
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  sell copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

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  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  IN THE SOFTWARE.
-->

<!-- Wrap everything into a macro to reduce file roundtrips (see #2213) -->
{% macro render_nav_item(nav_item, path, level) %}

  <!-- Determine class according to state -->
  {% set class = "md-nav__item" %}
  {% if nav_item.active %}
    {% set class = class ~ " md-nav__item--active" %}
  {% endif %}

  <!-- Main navigation item with nested items -->
  {% if nav_item.children %}

    <!-- Determine whether to render item as a section -->
    {% if "navigation.sections" in features and level == 1 + (
      "navigation.tabs" in features
    ) %}
      {% set class = class ~ " md-nav__item--section" %}
    {% endif %}

    <!-- Render item with nested items -->
    <li class="{{ class }} md-nav__item--nested">

      <!-- Active checkbox expands items contained within nested section -->
      {% set checked = "checked" if nav_item.active %}
      {% if "navigation.expand" in features and not checked %}
        <input
          class="md-nav__toggle md-toggle"
          data-md-toggle="{{ path }}"
          data-md-state="indeterminate"
          type="checkbox"
          id="{{ path }}"
          checked
        />
      {% else %}
        <input
          class="md-nav__toggle md-toggle"
          data-md-toggle="{{ path }}"
          type="checkbox"
          id="{{ path }}"
          {{ checked }}
        />
      {% endif %}

      <!-- Expand active pages -->
      <label class="md-nav__link" for="{{ path }}">
        {{ nav_item.title }}
        <span class="md-nav__icon md-icon"></span>
      </label>
      <nav
        class="md-nav"
        aria-label="{{ nav_item.title }}"
        data-md-level="{{ level }}"
      >
        <label class="md-nav__title" for="{{ path }}">
          <span class="md-nav__icon md-icon"></span>
          {{ nav_item.title }}
        </label>
        <ul class="md-nav__list" data-md-scrollfix>

          <!-- Render nested item list -->
          {% set base = path %}
          {% for nav_item in nav_item.children %}
            {{ render_nav_item(
              nav_item,
              path = base ~ "-" ~ loop.index,
              level = level + 1)
            }}
          {% endfor %}
        </ul>
      </nav>
    </li>

  <!-- Currently active page -->
  {% elif nav_item == page %}
    <li class="{{ class }}">
      {% set toc = page.toc %}

      <!-- Active checkbox expands items contained within nested section -->
      <input
        class="md-nav__toggle md-toggle"
        data-md-toggle="toc"
        type="checkbox"
        id="__toc"
      />

      <!-- Hack: see partials/toc.html for more information -->
      {% if toc | first is defined and "\x3ch1 id=" in page.content %}
        {% set toc = (toc | first).children %}
      {% endif %}

      <!-- Render table of contents, if not empty -->
      {% if toc | first is defined %}
        <label class="md-nav__link md-nav__link--active" for="__toc">
          {{ nav_item.title }}
          <span class="md-nav__icon md-icon"></span>
        </label>
      {% endif %}
      <a
        href="{{ nav_item.url | url }}"
        class="md-nav__link md-nav__link--active"
      >
        {{ nav_item.title }}
      </a>

      <!-- Show table of contents -->
      {% if toc | first is defined %}
        {% include "partials/toc.html" %}
      {% endif %}
    </li>

  <!-- Main navigation item -->
  {% else %}
    <li class="{{ class }}">
      <a href="{{ nav_item.url | url }}" class="md-nav__link">
        {{ nav_item.title }}
      </a>
    </li>
  {% endif %}
{% endmacro %}

<!-- Render current and nested navigation items -->
{{ render_nav_item(nav_item, path, level) }}