List child terms if parent but show nothing on children

Question

I have a taxonomy called region with a hierarchical structure;

• Southern Africa
  • Botswana
  • South Africa
  • Zambia
  • Zimbabwe

In my taxonomy-region.php template file I would like to list the child terms when on Southern Africa (parent) and show nothing when on Botswana (child).

I have the following code where I'd like it to display:

<?php 
$current_term = get_term_by( 'slug', get_query_var( 'term' ), get_query_var( 'taxonomy' )); ?>
<h5>Countries</h5>
<?php $cats = wp_list_categories( array(
    'parent' => $current_term->term_id,
    'taxonomy' => $current_term->taxonomy,
    'hide_empty' => 0,
    'hierarchical' => true,
    'depth' => 2,
    'title_li' => ''
    )); 
?>
<ul>
  <?php foreach ((array)$cats as $cat) {
    echo '<li><a href="'. get_category_link($cat).'" title="'. $cat->$cat_name .'">' . $cat->cat_name . '</a></li>'; }
  ?>
</ul>

Any help would be appreciated.

Answer 1

For reliability, you can get the current term being viewed from the queried object from $GLOBALS['wp_the_query']

$current_term = sanitize_term( $GLOBALS['wp_the_query']->get_queried_object() );

To answer your question, if Southern Africa is top level, it should have a parent term ID of 0. All child terms should have a numeric value as parent which corresponds to the parent term id they belong to.

With this in mind, you can simply check the value of $current_term->parent, and if the value is not 0, hide your code

$current_term = sanitize_term( $GLOBALS['wp_the_query']->get_queried_object() );
if ( 0 == $current_term->parent ) {
    // This is a top level page, show our code

        // ADD YOUR CODE HERE

}

Just another tip, I would use get_terms() for my list