update_field gallery image without deleting existing

• obra

• July 7, 2014 at 6:40 am

Hello, how can i add images in a gallery in the front end by programmatically? I am using this:

$attachment_id_gallery[] = insert_attachment($file_id,$post_id,false);
update_field( ‘field_xxxxxxxxxxxx’, $attachment_id_gallery , $post_id );

But when i upload one or more images files, the old ones are replace by the new one. I just need to add the new one to the existing.

Excuse my english.