static Control* factory (Surface& surface, Button::ID bid, int id, const std::string&, Group& group);
static int name_to_id (const std::string& name);
static std::string id_to_name (Button::ID);
static Control* factory (Surface& surface, Button::ID bid, int id, const std::string&, Group& group);
static int name_to_id (const std::string& name);
static std::string id_to_name (Button::ID);