title: wp_nav_menu() : custom walker
body: <p>I am starting at WP theming, and it's been more than one day that I am looking to do the similar menu with the wp_nav_menu function :</p>
  
  <pre><code>      &lt;div class="ui simple dropdown item"&gt;
            CATEGORY NAME WITH SUB-CATEGORIES
          &lt;i class="dropdown icon"&gt;&lt;/i&gt;
            &lt;div class="menu"&gt;
              &lt;a href="link_to_sub_category"&gt;&lt;div class="item" &gt;Sub Category 1&lt;/div&gt;&lt;/a&gt;
              &lt;a href="link_to_sub_category"&gt;&lt;div class="item" &gt;Sub Category 2&lt;/div&gt;&lt;/a&gt;
            &lt;/div&gt;
        &lt;/div&gt;
  </code></pre>
  
  <p>Also, if there's no sub categories, the HTML output would be like this :</p>
  
  <pre><code>      &lt;div class="ui simple dropdown item"&gt;
            CATEGORY NAME WITHOUT SUB-CATEGORY
        &lt;/div&gt;
  </code></pre>
  
  <p>What do I have to put in my functions.php ? 
  Any hint or any help would be very much appreciated !</p>
  
  <p>Thanks.</p>