#include <gre/gre.h>                
gr_application_event_listener_t gr_application_add_event_listener(
  gr_application_t *app, 
  const char *event,
  gr_event_listener_t handler,
  void *data


The gr_application_add_event_listener function provides an interface associate a callback/handler to associate with a Storyboard event.

        app A pointer to an application handle created using gr_application_create_args.
        event The event to add a listener for
        handler The handler to call for this event
        data User defined data which is passed to the handler

        A pointer to the created listener.

The gr_application_add_event_listener function is the method used to associate a callback/handler to execute with a Storyboard engine event. When the event occurs the handler will execute in the main Storyboard execution thread