bbPress.org

@jsteckler1: We use GF to set a custom field called “_mu_autogenerated_post_to” and then our code looks like this:

/*
 * Small fix for posting new introductions to the introductions thread
 * Would be nice to use the GF hook but post_id not set with Custom Post Types addon -_-
 */
function set_post_parent($post_id)
{
    if (get_post_meta($post_id,"_mu_autogenerated_post_to",true))
    {
        remove_action( 'save_post', 'set_post_parent',10); // Avoid infinite loop when wp_update_post calls save_post
        $target_discussion = get_post_meta($post_id,"_mu_autogenerated_post_to",true);
        error_log("Detected new _mu_autogenerated_post_to " . $target_discussion);
        wp_update_post( array('ID' => $post_id,'post_parent'=>$target_discussion) );
        error_log("Updated post parent.");
        add_action( 'save_post', 'set_post_parent',10);
    }    
    else
    {
       // error_log("Ignoring non-_mu_autogenerated_post_to post creation");
    }
}
add_action( 'save_post', 'set_post_parent',10);

Hope that helps!