function open_source($table, $handler = '', $args = 0)
 {
     $c = new cursor_sql($table);
     $c->set_source($table);
     $this->open_context($c);
     $this->open_form($this->make_event($handler, $args));
     $this->open_table();
     $_is_open = true;
 }
function _get_index(&$app, $parent, $ref_parent, $table, $id)
{
    $id_parent = $app->db->column($table, $ref_parent, $id);
    $c = new cursor_sql();
    $c->set_source($table);
    $c->query("{$ref_parent}={$id_parent}");
    $i = 1;
    while ($row = $c->get()) {
        if ($row['id'] == $id) {
            return array($i, $c->size());
        }
        $i++;
    }
}