Reply To: Frontend Search Settings: Any post type

In theory, maybe by adding “fake” filters to the front-end with any labels you choose, then processing them during the query arguments filter could actually work.

So for example:

add_filter('asp_pre_get_front_filters', 'asp_add_a_filter', 10, 2);
function asp_add_a_filter($filters, $type) {
  foreach ($filters as $k => &$filter) {    
	if ( $filter->type() == 'post_type' ) {
           $filter->add(array(
               'label' => 'My Post Type',
               'selected' => false,
               'value' => 'my_post_type'
           ));
	}
  }
  return $filters;
}

This should add an additional filter to a post type filter with a label “My post Type” and value “my_post_type”. When this is selected, it is passed to the query arguments.

add_filter("asp_query_args", "asp_query_args_change", 10, 2);
function asp_query_args_change($args, $search_id) {
  // The my_post_type was selected
  if ( in_array('my_post_type', $args['post_type']) ) {
	$args['post_type'] = array('post', 'page', 'other_post_type');
  }
  return $args;
}

This then detects if the ‘my_post_type’ was selected, and changes the post type arguments to whatever you need.

In theory this should work, but I honestly don’t recall if there is any existence check before or after the query arguments for post types – in which case this can be an issue, and probably will not work.