Display all posts in a custom post type, grouped by a custom taxonomy. How to sort the posts alphabetically and the terms by ID?

Question

I have a custom post type called as books with taxonomy named as genre. Inside the genre there are a number of terms such as horror, romance,comedy`, etc.

I want to display them in the archive page, grouped by each terms. So I use Chip Bennet's fantastic code.

However, I have problem with the sorting.

The code sorts the terms according to its alphabetical names, and the posts according to the recentness. So it appears like this:

• Comedy
  • Newest book
  • Not so new book
  • Old book
• Horror
  • etc the same: newest - not new - old
• Romance
• Sci-fi

Meanwhile, I need it to be sorted differently. I want to sort the terms according to the tag_ID, and the book list according to its alphabetical name. So it should look like this:

• Sci-fi (tag_ID number 1)
  • A
  • B
  • C
  • etc
• Romance (tag_ID number 2)
• Comedy (tag_ID number 3)
• Horror (tag_ID number 4)

I tried to mess with the query, so it looks like this

$member_group_query = new WP_Query( array(
    'post_type' => 'member',
    'orderby ' => 'name', // sort the books alphabetically
    'tax_query' => array(
        array(
            'taxonomy' => 'member_group',
            'field' => 'slug',
            'terms' => array( $member_group_term->slug ),
            'orderby ' => 'ID', // sort the genre according to its ID
            'operator' => 'IN'
        )
    )
) );

But nothing changes. I checked Wordpress Codex on WP_Query to make sure but still no avail. Any help?

Answer 1

I think you need first to sort the genre terms in the other query:

$genres = get_terms( 'genre', 'orderby=term_id' );

And then on the posts query for each genre (like Chip Bennet's approach):

$member_group_query = new WP_Query( array(
    'post_type' => 'member',
    'orderby' => 'name',
    'tax_query' => array(
        array(
            'taxonomy' => 'member_group',
            'field' => 'slug',
            'terms' => array( $member_group_term->slug ),
            'operator' => 'IN'
        )
    )
) );