vban-cmd-python/vban_cmd/subject.py
onyx-and-iris ee10060724 changes to observers thread.
minor version bump
2022-06-20 00:01:30 +01:00

40 lines
952 B
Python

class Subject:
"""Adds support for observers"""
def __init__(self):
"""list of current observers"""
self._observers = list()
@property
def observers(self) -> list:
"""returns the current observers"""
return self._observers
def notify(self, modifier=None):
"""run callbacks on update"""
[o.on_update(modifier) for o in self._observers]
def add(self, observer):
"""adds an observer to _observers"""
if observer not in self._observers:
self._observers.append(observer)
else:
print(f"Failed to add: {observer}")
def remove(self, observer):
"""removes an observer from _observers"""
try:
self._observers.remove(observer)
except ValueError:
print(f"Failed to remove: {observer}")
def clear(self):
"""clears the _observers list"""
self._observers.clear()