Show all terms in a custom taxonomy with all child terms wrapped in a ul

Question

Is there a way that I can list all the terms within a custom taxonomy in an unordered list and wrap all child terms in another unordered list?

For example;

<ul class="menu">

    <li><a href="#">Parent 1</a></li>
    <li>
        <a href="#">Parent 2</a>

        <ul class="sub-menu">

            <li><a href="#">Child of Parent 2</a></li>
            <li><a href="#">Child of Parent 2</a></li>
            <li><a href="#">Child of Parent 2</a></li>

        </ul>

    </li>
    <li><a href="#">Parent 3</a></li>

</ul>

Answer 1

You can take a look at the Wordpress function wp_list_categories(). If you want to display all the terms within a given custom taxonomy you can for example use:

<?php 
$args = array(
  'taxonomy'     => 'my_custom_taxonomy_slug',
  'orderby'      => 'name',
  'hide_empty'   => 0,
  'title_li'     => '',
  'hierarchical' => 1,
  'walker'       => null,
);
?>
<ul class="menu">
<?php wp_list_categories( $args ); ?>
</ul>

If you need to adjust the html structure, you can use a custom walker that extends either Walker_Category or Walker.

You can read more about it here in the Codex:

http://codex.wordpress.org/Template_Tags/wp_list_categories