lily/include/dispatcher.hh

   1 /*
   2   dispatcher.hh -- declare Dispatcher
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2005 Erik Sandberg  <mandolaerik@gmail.com>
   7 */
   8
   9 #ifndef DISPATCHER_HH
  10 #define DISPATCHER_HH
  11
  12 #include "listener.hh"
  13 #include "stream-event.hh"
  14
  15 class Dispatcher
  16 {
  17   /* Hash table. Each event-class maps to a list of listeners. */
  18   SCM listeners_;
  19   /* alist of dispatchers that we listen to. Each entry is a
  20      (dist . priority) pair. */
  21   SCM dispatchers_;
  22   SCM listen_classes_;
  23   DECLARE_LISTENER (dispatch);
  24   /* priority counter. Listeners with low priority receive events
  25      first. */
  26   int priority_count_;
  27   void internal_add_listener (Listener, SCM event_class, int priority);
  28 public:
  29   Dispatcher ();
  30   void broadcast (Stream_event *ev);
  31   void add_listener (Listener, SCM event_class);
  32   void remove_listener (Listener, SCM event_class);
  33   void register_as_listener (Dispatcher *dist);
  34   void unregister_as_listener (Dispatcher *dist);
  35 protected:
  36   DECLARE_SMOBS (Dispatcher);
  37 };
  38
  39 DECLARE_UNSMOB (Dispatcher, dispatcher);
  40
  41 #endif // DISPATCHER_HH