Upgrade wp_list_categories() to wp_nav_menu()

In this third installment in the upgrade to wp_nav_menu() series of posts, I will be dealing with moving from wp_list_categories() to wp_nav_menu().

Let’s start with the same basic outline and list the default options for each function. We will start with wp_nav_menu() ¹ first:

wp_nav_menu( array(
    'menu'              => '',
    'container'         => 'div',
    'container_class'   => '',
    'container_id'      => '',
    'menu_class'        => 'menu',
    'menu_id'           => '',
    'echo'              => true,
    'fallback_cb'       => 'wp_page_menu',
    'before'            => '',
    'after'             => '',
    'link_before'       => '',
    'link_after'        => '',
    'depth'             => 0,
    'walker'            => '',
    'theme_location'    => ''
    ) );

We follow with wp_list_categories() ^{2, 3} which is often wrapped in a <ul class=”menu”> tag:

<ul class="menu">
wp_list_categories( array(
    'include'           => '',
    'exclude'           => '',
    'exclude_tree'      => '',
    'child_of'          => 0,
    'hide_empty'        => 1,
    'orderby'           => 'name',
    'order'             => 'ASC',
    'use_desc_for_title'=> 1,
    'number'            => NULL,
    'hierarchical'      => true,
    'show_count'        => 0,
    'pad_counts'        => 0,
    'style'             => 'list',
    /* 'style' set to list "creates list items for an unordered list" */
    'show_option_all'   => '',
    'show_option_none'  => __('No categories'),
    'show_last_update'  => 0,
    'feed'              => '',
    'feed_type'         => '',
    'feed_image'        => '',
    'current_category'  => 0,
    'taxonomy'          => 'category',
    'title_li'          => __( '' ),
    /* 'title_li' set to '' for menus from the default 'Categories' */
    'echo'              => 1,
    'depth'             => 0,
    'walker'            => 'Walker_Category'
    ) );
</ul>

Here is the break-down of the wp_list_categories() default options from above:

• 'include' – not used
• 'exclude' – not used
• 'exclude_tree' – not used
• 'child_of' – not used
• 'hide_empty' – not used
• 'orderby' – not used
• 'order' – not used
• 'use_desc_for_title' – not used
• 'number' – not used
• 'hierarchical' – not used
• 'show_count' – not used
• 'pad_counts' – not used
• 'style' – not used
• 'show_option_all' – not available
• 'show_option_none' – not available
• 'show_last_update' – not available
• 'feed' – not available
• 'feed_type' – not available
• 'feed_image' – not available
• 'current_category' – not available
• 'taxonomy' – not available
• 'title_li' – not used
• 'echo' – similar to wp_nav_menu(); true versus 1 as value
• 'depth' – same as wp_nav_menu()
• 'walker' – see below for additional notes

Although there are great many options available to be used with wp_list_categoires() most are not used (as noted in the list above) in place of the user interface of wp_nav_menu() found under Appearance | Menu in the dashboard. The options that are marked as “not available” are currently not directly supported by wp_nav_menu() without the application of filters. The last few options remaining match up almost exactly with wp_page_nav() in a similar fashion as was shown with wp_list_pages().

Just like the wp_list_pages() consideration, the wp_nav_menu() fallback_cb option may be set to 'fallback_cb' => 'wp_list_categories'. This backward compatibility may also be addressed with a custom function as was noted, too.

Note: In most cases you would leave the wp_nav_menu() 'walker' option set to its default NULL although wp_list_categories() uses its own default walker class.