'Add a custom event handler that will be executed whenever
its event is manually triggered.
:param name: The name of the event that will trigger
this handler.
:param pointer: The function to execute.
:param threaded: If set to ``True``, the handler will execute
in its own thread. Defaults to ``False``.
:param disposable: If set to ``True``, the handler will be
discarded after one use. Defaults to ``False``.'

def add_event_handler(self, name, pointer, threaded=False, disposable=False):

    if (not (name in self.__event_handlers)):
        self.__event_handlers[name] = []
    self.__event_handlers[name].append((pointer, threaded, disposable))
