/
eventable.py
43 lines (37 loc) · 1.09 KB
/
eventable.py
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import logging
# TODO: use queue's so that events happen in the order
# they are fired
class Eventable(object):
"""
base class for object you want to handle events
uses a simple event tracking system
"""
def __init__(self):
self.__handlers = {}
def on(self,event,handler):
"""
add a listener
"""
logging.debug('adding handler: %s' % event)
self.__handlers.setdefault(event,[]).append(handler)
return self
def un(self,event,handler):
"""
remove a listener
"""
if event in self.__handlers:
try:
self.__handlers[event].remove(handler)
except ValueError:
pass # nothing to remove
return self
def fire(self,event,*args,**kwargs):
"""
fire the event. aka call the handlers
and pass them the args, kwargs
"""
logging.debug('firing %s' % event)
for handler in self.__handlers.get(event,[]):
logging.debug('firing handler')
handler(*args,**kwargs)
return self