foreach ($order as $v) {
        $post = get_post($v['post_id']);
        $post->menu_order = $v['menu_order'];
        if ($post_id == $v['post_id']) {
            $post->post_parent = $parent;
        }
        wp_update_post($post);
    }
    header('Content-Type: application/json');
    echo json_encode(array('success' => true, 'order' => $order));
    die;
}
add_action('wp_ajax_rw_buddypress_docs_tree_change_node', 'rw_buddypress_docs_tree_change_node');
add_filter('bp_docs_parent_dropdown_query_args', function ($array) {
    include_once 'RW_BuddyPress_Docs_Tree.php';
    return RW_BuddyPress_Docs_Tree::bd_get_query_args($array);
});
function rw_docs_disable_folder($return)
{
    return false;
}
//add_filter( 'bp_docs_enable_folders', 'rw_docs_disable_folder' );
/**
 * save bp-actifity-filter cookie to user metadata
 */
function activity_widget_filter()
{
    if (get_current_user_id() != 0) {
        $cookie = $_COOKIE['bp-activity-filter'];
        update_user_meta(get_current_user_id(), 'bp-activity-filter', $cookie);
    }
 public static function bd_get_query_args($defaults)
 {
     global $bp;
     $qargs = array('posts_per_page' => -1, 'paged' => 0, 'orderby' => 'menu_order', 'order' => 'ASC', 'post_type' => 'bp_doc', 'post_status' => 'publish', 'suppress_filters' => true);
     $tree = new RW_BuddyPress_Docs_Tree();
     $group_id = $tree->bd_docs_get_current_group_id();
     if ($group_id) {
         $qargs["tax_query"] = array(array("taxonomy" => "bp_docs_associated_item", "field" => "slug", 'terms' => array('bp_docs_associated_group_' . $group_id)));
     } else {
         $qargs['author'] = $bp->loggedin_user->id;
     }
     return wp_parse_args($qargs, $defaults);
 }
        <?php 
bp_docs_info_header();
?>
    </div>

    <ul class="docs-tree tree-node">

    <?php 
/**
 * Created by PhpStorm.
 * User: Joachim
 * Date: 12.03.2016
 * Time: 10:06
 */
include_once get_stylesheet_directory() . '/RW_BuddyPress_Docs_Tree.php';
RW_BuddyPress_Docs_Tree::the_docs_tree('ul', $group_id);
?>

    </ul>

</div>

<script>

    jQuery().ready(function($){

        var  options = {
            insertZone:50,
            insertZonePlus:true,
            listSelector:'ul',
            placeholderCss: {'background-color':'#FFC3B7'},