Custom Taxonomy Default Term(s) for when it’s left blank
After looking through the WP codex and various plugins, I couldn’t find anywhere to set a custom taxonomy default term. WordPress has allowed us to create custom taxonomies for a while. Before we only had categories and tags hard coded in core. One feature from those days that didn’t seem to make it to the custom taxonomies of today is the possibility to select a default taxonomy term if none are selected. Did you know about this feature? Odds are you did, even if you didn’t realize it. Have you ever seen that ‘uncategorized’ category? That was the default category added for any content that didn’t have a specific category and was left, well, uncategorized.
An annoying feature if you weren’t expecting it, but nice to have if you took the moment to actually set up your default properly. I was working on a project recently with custom post types and custom taxonomies and suddenly needed this feature, but it didn’t seem to exist, so a few google’s later I found this nice snippet from Micheal Fields. Adopting the hook and adding some to allow for custom post types I wanted to share it here for my own safe keeping as well as the benefit of the community.
To Code Custom Taxonomy Default Terms
[cc lang=”php”]
/**
* Define default terms for custom taxonomies in WordPress 3.0.1
*
* @author Michael Fields http://wordpress.mfields.org/
* @props John P. Bloch http://www.johnpbloch.com/
* @props Evan Mulins https://circlecube.com/circlecube/
*
* @since 2010-09-13
* @alter 2013-01-31
*
* @license GPLv2
*/
function mfields_set_default_object_terms( $post_id, $post ) {
if ( ‘publish’ === $post->post_status && $post->post_type === ‘your_custom_post_type’ ) {
$defaults = array(
‘your_taxonomy_id’ => array( ‘your_term_slug’ )
//’your_taxonomy_id’ => array( ‘your_term_slug’, ‘your_term_slug’ )
);
$taxonomies = get_object_taxonomies( $post->post_type );
foreach ( (array) $taxonomies as $taxonomy ) {
$terms = wp_get_post_terms( $post_id, $taxonomy );
if ( empty( $terms ) && array_key_exists( $taxonomy, $defaults ) ) {
wp_set_object_terms( $post_id, $defaults[$taxonomy], $taxonomy );
}
}
}
}
add_action( ‘save_post’, ‘mfields_set_default_object_terms’, 100, 2 );
[/cc]
This code hooks to ‘save_post’ and fires when the post is saved. It will check the post status and only execute if the post status is set to publish. My addition will also check the post type against your custom post type. Then it sets the default for any taxonomy that you want to set a default for. Either a single term or multiple terms can be set as the default taxonomy term. If you want multiple default terms then you just use a comma separated list. This hook will then load the existing taxonomies and if they are not yet set on the post it will set them to your designated default(s). It’s nice and flexible as you can have multiple taxonomy defaults set quickly in the defaults array. Thanks Michael!
Set Default Terms for your Custom Taxonomies via Michael Fields » Set Default Terms for your Custom Taxonomies.