User Contributed Notes

1. Skip to note 5 content

   
   Roy Tanck
   
   
   7 years ago
   

   You must log in to vote on the helpfulness of this noteVote results for this note: 5You must log in to vote on the helpfulness of this note

   The example below eliminates the need for parse_query when filtering based on taxonomy. It uses the taxonomy slug as URL parameter, just like WordPress does out of the box. The example adds filter dropdowns for two taxonomies, and allows for boolean AND filtering.

   add_action( 'restrict_manage_posts', 'add_admin_filters', 10, 1 );
   
   public function add_admin_filters( $post_type ){
   	if( 'my_post_type' !== $post_type ){
   		return;
   	}
   	$taxonomies_slugs = array(
   		'my_taxonomy',
   		'my_other_taxonomy'
   	);
   	// loop through the taxonomy filters array
   	foreach( $taxonomies_slugs as $slug ){
   		$taxonomy = get_taxonomy( $slug );
   		$selected = '';
   		// if the current page is already filtered, get the selected term slug
   		$selected = isset( $_REQUEST[ $slug ] ) ? $_REQUEST[ $slug ] : '';
   		// render a dropdown for this taxonomy's terms
   		wp_dropdown_categories( array(
   			'show_option_all' =>  $taxonomy->labels->all_items,
   			'taxonomy'        =>  $slug,
   			'name'            =>  $slug,
   			'orderby'         =>  'name',
   			'value_field'     =>  'slug',
   			'selected'        =>  $selected,
   			'hierarchical'    =>  true,
   		) );
   	}
   }

2. Skip to note 6 content

   
   Aurovrata Venet
   
   
   9 years ago
   

   You must log in to vote on the helpfulness of this noteVote results for this note: 2You must log in to vote on the helpfulness of this note

   Use this hook to add a custom taxonomy filter for your post table,

   add_action( 'restrict_manage_posts', 'my_post_type_filter', 10, 2 );
   function my_post_type_filter( $post_type, $which ) {
   	if ( 'my-post' !== $post_type ) {
   		return; //check to make sure this is your cpt
   	}
   
   	$taxonomy_slug = 'my-post-type';
   	$taxonomy      = get_taxonomy($taxonomy_slug);
   	$selected      = '';
   	$request_attr  = 'my_type'; //this will show up in the url
    
   	if ( isset( $_REQUEST[ $request_attr ] ) ) {
   		$selected = $_REQUEST[ $request_attr ]; //in case the current page is already filtered
   	}
       
   	wp_dropdown_categories(array(
   		'show_option_all' =>  __("Show All {$taxonomy->label}"),
   		'taxonomy'        =>  $taxonomy_slug,
   		'name'            =>  $request_attr,
   		'orderby'         =>  'name',
   		'selected'        =>  $selected,
   		'hierarchical'    =>  true,
   		'depth'           =>  3,
   		'show_count'      =>  true, // Show number of post in parent term
   		'hide_empty'      =>  false, // Don't show posts w/o terms
   	) );
   }

3. Skip to note 7 content

   
   Aurovrata Venet
   
   
   9 years ago
   

   You must log in to vote on the helpfulness of this noteVote results for this note: 1You must log in to vote on the helpfulness of this note

   To add a custom filter based on a meta field for example, you can build a custom dropdown filter,

   add_action('restrict_manage_posts','location_filtering',10);
   function location_filtering($post_type){
       if('my-custom-post' !== $post_type){
         return; //filter your post
       }
       $selected = '';
       $request_attr = 'my_loc';
       if ( isset($_REQUEST[$request_attr]) ) {
         $selected = $_REQUEST[$request_attr];
       }
       //get unique values of the meta field to filer by.
   	$meta_key = 'my_custom_field_location';
   	global $wpdb;
   	$result = $wpdb->get_col( 
   		$wpdb->prepare( "
   			SELECT DISTINCT pm.meta_value FROM {$wpdb->postmeta} pm
   			LEFT JOIN {$wpdb->posts} p ON p.ID = pm.post_id
   			WHERE pm.meta_key = '%s' 
   			AND p.post_status IN ('publish', 'draft')
   			ORDER BY pm.meta_value", 
   			$meta_key
   		) 
       );
      //build a custom dropdown list of values to filter by
       echo '<select id="my-loc" name="my_loc">';
       echo '<option value="0">' . __( 'Show all locations', 'my-custom-domain' ) . ' </option>';
       foreach($results as $location){
         $select = ($org->ID == $selected) ? ' selected="selected"':'';
         echo '<option value="'.$location.'"'.$select.'>' . $location . ' </option>';
       }
       echo '</select>';
     }

   next we need to ensure the admin query returns the correct set of filtered posts by hooking onto the ‘parse_query’ filter,

   add_filter( 'parse_query', 'filter_request_query' , 10);
   function filter_request_query($query){
       //modify the query only if it admin and main query.
       if( !(is_admin() AND $query->is_main_query()) ){ 
         return $query;
       }
       //we want to modify the query for the targeted custom post and filter option
       if( !('my-custom-post' === $query->query['post_type'] AND isset($_REQUEST['my_loc']) ) ){
         return $query;
       }
       //for the default value of our filter no modification is required
       if(0 == $_REQUEST['my_loc']){
         return $query;
       }
      //modify the query_vars.
       $query->query_vars = array(array(
         'field' => 'my_custom_field_location',
         'value' => $_REQUEST['my_loc'],
         'compare' => '=',
         'type' => 'CHAR'
       ));
       return $query;
     }

   To build more complex meta field queries, lookup the documentation for the WP_Meta_Query object.

4. Skip to note 8 content

   
   Aurovrata Venet
   
   
   9 years ago
   

   You must log in to vote on the helpfulness of this noteVote results for this note: 0You must log in to vote on the helpfulness of this note

   Use this hook to add a custom taxonomy filter for your post table,

   add_action('restrict_manage_posts','my_post_type_filter',10,2);
   function my_post_type_filter($post_type, $which){
       if('my-post' !== $post_type){
         return; //check to make sure this is your cpt
       }
       $taxonomy_slug = 'my-post-type';
       $taxonomy = get_taxonomy($taxonomy_slug);
       $selected = '';
       $request_attr = 'my_type'; //this will show up in the url
       if ( isset($_REQUEST[$request_attr] ) ) {
         $selected = $_REQUEST[$request_attr]; //in case the current page is already filtered
       }
       wp_dropdown_categories(array(
         'show_option_all' =>  __("Show All {$taxonomy->label}"),
         'taxonomy'        =>  $taxonomy_slug,
         'name'            =>  $request_attr,
         'orderby'         =>  'name',
         'selected'        =>  $selected,
         'hierarchical'    =>  true,
         'depth'           =>  3,
         'show_count'      =>  true, // Show number of post in parent term
         'hide_empty'      =>  false, // Don't show posts w/o terms
       ));
     }

   to ensure the post table is correctly filtered, the post query needs to be modified to filter the selected term. This is done by hooking the 'parse_query' filter,

   add_filter( 'parse_query', 'filter_request_query' , 10);
   function filter_request_query($query){
       //modify the query only if it is admin and main query.
       if( !(is_admin() AND $query->is_main_query()) ){ 
         return $query;
       }
       //we want to modify the query for the targeted custom post.
       if( 'my-post' !== $query->query['post_type'] ){
         return $query;
       }
       //type filter
       if( isset($_REQUEST['my_type']) &&  0 != $_REQUEST['my_type']){
         $term =  $_REQUEST['my_type'];
         $taxonomy_slug = 'my-post-type';
         $query->query_vars['tax_query'] = array(
           array(
               'taxonomy'  => $taxonomy_slug,
               'field'     => 'ID',
               'terms'     => array($term)
           )
         );
       }
       return $query;
   }