
I had a similar requirement to yours and found this when searching for a solution.
I have managed to get this working using the acf/fields/post_object/query filter.
The way it brings in the information is a bit harder to debug as it’s all AJAX, but using WP_DEBUG_LOG and error_log to see what data was parsing through helped me come to the solution:
function cxx_event_balance_individual_option( $args, $field, $post_id ) {
// $post_id comes in here as term_# so we need to remove 'term_' to get the term ID
$prefix = 'term_';
// Also if you are creating a new taxonomy, post_id = 'term_0' so then there's no point in adding a filter
if ( 'term_0' != $post_id && substr( $post_id, 0, strlen( $prefix )) == $prefix ) {
// Set $term_id to the ID part of $post_id
$term_id = substr( $post_id, strlen( $prefix ) );
// And adjust the query to filter by specific taxonomy term
$args['tax_query'] = array(
array(
'taxonomy' => 'product_event',
'field' => 'term_id',
'terms' => $term_id,
),
);
}
return $args;
}
Hope this helps you out.