Recognisers associated this way are store very similar to attributes associated with object->attribute. If the graphical is saved to a file using object->save_in_file, the recognisers will be saved with the graphical object.

Using class-level programming, recognisers mat be associated with graphical objects in two ways: by redefining the graphical->initialise method, calling graphical->recogniser to associate event handling or by redefining the class graphical->event method.

The following example defines movable_box as a class:

:- pce_begin_class(movable_box, box).

:- pce_global(@movable_box_recogniser,
                          new(move_gesture)).

event(MB, Ev:event) :->
        "Associate @movable_box_recogniser"::
        (   send(MB, send_super, event, Ev)
        ;   send(@movable_box_recogniser, event, Ev)
        ).

:- pce_end_class.

See also: class gesture, class event, graphical->prepend_recongiser, event->post, pce_global/2.