Query Custom Post by Category

Question

I try to query custom post type called news by a category called Alumni with ID=160.

When I use such arguments, as a result, I get all my custom posts without Alumni category:

$args = array(
  'posts_per_page' => -1,
  'post_type' => 'news',
  'orderby' => 'date',
  'order' => 'DESC',
  'category__not_in' => 160
);
$loop = new WP_Query( $args );

<?php while ( $loop->have_posts() ) : $loop->the_post();?>
...
<?php endwhile; ?>

However, changing category__not_in to category__in gives an empty list but I would expect the opposite of the initial result. I can't really understand where I make a mistake.

Also, I tried using cat and category_name instead and I played around with different categories but results were always the same.

In my research I came across 'tax_query' but I can't get it to work as well. The documentation is not quite clear for me.

Answer 1

Are these custom taxonomies or the regular categories?

if they are just categories you should use:

$args = array(
  'posts_per_page' => -1,
  'post_type' => 'news',
  'orderby' => 'date',
  'order' => 'DESC',
  'category_name' => 'Alumni'
);
$loop = new WP_Query( $args );

<?php while ( $loop->have_posts() ) : $loop->the_post();?>
...
<?php endwhile; ?>

if you want to use it by id

use:

'cat' => 160 

instead of

'category_name' => 'Alumni'

Answer 2

Have you tried using something like this in the array, Had a similar problem earlier which this solved.

'taxonomy' => 'your_taxonomy_name',

Or something like :

    'tax_query' => array(
        'taxonomy' => 'your_taxonomy_name',
        'terms' => 'Alumni',
        'field' => 'slug',
        'include_children' => true,
),

Answer 3

To get custom post type posts with specific category use custom taxonomy

Register the taxonomy name of the custom post type like categories and then assign a category to each post when you added new post. Here is the example of the code

  add_action( 'init', 'news_my_taxonomy');
  function news_my_taxonomy(){
 // custom post type taxonomies
    $labels = array(
    'name' => 'Categories',
    'singular_name' => 'Category',
    'add_new' => 'Add Category',
    'add_new_item' => 'Add New Category',
    'all_items' => 'All Categories',
    'edit_item' => 'Edit Item',
    'new_item' => 'New Item',
    'view_item' => 'View Item',
    'update_item' => 'Update Category',
    'search_items' => 'Search Categories',
    'not_found' => 'No record found',
    'not_found_in_trash' => 'No items found in trash',
    'parent_item_colon' => 'Parent Item',
    'menu_name' => 'Categories'
    );
    $args = array(
        'labels' => $labels,
        'hierarchical' => true,
        'has_archive' => true,
        'rewrite' => array('slug' => 'news_category'),
        'show_ui' => true,
        'show_admin_column' => true,
        'query_var' => true,
        );
        register_taxonomy('news_category', array('news'), $args);
}

then

create taxonomy template page 'taxonomy-news_category.php'

and add the query to get the posts with this category name

   $cat_name = single_cat_title;
   $args = array( 'category_name' => $cat_name, 'posts_per_page' => 12, 'order'=> 'ASC', 'post_type' => 'news', 'paged' => $paged);

All the work is done.Good luck