Taxonomies
##########

Custom taxonomies could be found inside ``horizon/includes/taxonomies`` folder. Before you start working with taxonomies, make sure that you are familiar with all nuances of `register_taxonomy`_ function.

.. _`register_taxonomy`: https://codex.wordpress.org/Function_Reference/register_taxonomy

Adding new taxonomy to listing
==============================

.. code-block:: php
    :linenos:

    add_action( 'init', 'my_custom_taxonomy', 11 );
    add_action( 'parent_file', 'menu', 11 );
    add_action( 'admin_menu', 'admin_menu', 11 );
    
    function my_custom_taxonomy() {
        $custom_taxonomy_labels = array(
            'name'              => __( 'Custom Taxonomies', 'domain' ),
            'singular_name'     => __( 'Custom Taxonomy', 'domain' ),
            'search_items'      => __( 'Search Custom Taxonomy', 'domain' ),
            'all_items'         => __( 'All Custom Taxonomies', 'domain' ),
            'parent_item'       => __( 'Parent Custom Taxonomy', 'domain' ),
            'parent_item_colon' => __( 'Parent Custom Taxonomy:', 'domain' ),
            'edit_item'         => __( 'Edit Custom Taxonomy', 'domain' ),
            'update_itm'        => __( 'Update Custom Taxonomy', 'domain' ),
            'add_new_item'      => __( 'Add New Custom Taxonomy', 'domain' ),
            'new_item_name'     => __( 'New Custom Taxonomy', 'domain' ),
            'menu_name'         => __( 'Custom Taxonomies', 'domain' ),
        );
    
        register_taxonomy( 'custom_taxonomies', Horizon_Post_Types::get_listing_post_types    array    (
            'labels'            => $custom_taxonomy_labels,
            'hierarchical'      => true,
            'query_var'         => 'custom-taxonomy',
            'rewrite'           => array( 'slug' => __( 'custom-taxonomy', 'domain' ) ),
            'public'            => true,
            'show_ui'           => true,
            'show_admin_column' => true,
        ) );
    }
    
    function menu( $parent_file ) {
        global $current_screen;
        $taxonomy = $current_screen->taxonomy;
    
        if ( 'custom_taxonomies' == $taxonomy ) {
            return 'lexicon';
        }
    
        return $parent_file;
    }
    
    function admin_menu( $parent_file ) {
        add_submenu_page( 
            'lexicon', 
            __( 'Custom Taxonomies', 'domain' ), 
            __( 'Custom Taxonomies', 'domain' ), 
            'edit_posts', 
            'edit-tags.php?taxonomy=custom_taxonomies', 
            false 
        );
    }    


Removing taxonomy
=================

All taxonomies definition are wrapped in init hooks so it is easy to remove custom taxonomy only by defining remove_action(). Below you can see example how to remove **colors** taxonomy.

.. code-block:: php
    :linenos:

    remove_action( 'init', array( 'Horizon_Taxonomy_Colors', 'definition' ) );


Changing taxonomy slug
======================

To change already existing taxonomy, you need to remove it at first and then register it again using approaches above.