It looks like you have everything you need except a `pre_get_posts’ filter.
I recently did this on a site I was working on. Basically, you need to add a filter.
Here is the filter that I used:
function reference_pre_get_posts($query) {
// only in admin
if (!is_admin() || !$query->is_main_query()) {
return;
}
if ($query->query_vars['post_type'] == 'reference' &&
($orderby = $query->get('orderby'))) {
switch ($orderby) {
case 'featured':
case 'reference_featured':
$query->set('meta_key', 'reference_featured');
$query->set('orderby', 'meta_value_num');
break;
default:
// do nothing
break;
}
} // end if reference and orderby
}
basically it test to see if we’re in the admin and if we are querying my post type and it it is one of the meta_keys I’ve set up as a sortable field. If it is then I add the meta_key that it needs to be ordered by and change the orderby to meta_value.
Hope this helps
