def cached(f):
name = f.__name__
def wrapper(self):
- if self.cache is None:
+ cache = self.cache
+ if cache is None:
return f(self)
- if name not in self.cache:
- self.cache[name] = (True, f(self))
- return self.cache[name][1]
+ if name not in cache:
+ cache[name] = (True, f(self))
+ return cache[name][1]
return wrapper
+class ElementError(Exception):
+ def __init__(self, message):
+ self.message = message
+
+ def __str__(self):
+ return self.message
+
class Element(object):
CHANGED_DEFAULT = 0 # initial "pull" state
CHANGED_ALL = 1 # really everything changed
# we should not disconnect from upstream if
# there are still elements depending on us.
assert len(self.downstream_elements) == 0, "there are still downstream elements left"
-
+
# Sources don't have a source themselves. don't do anything here.
if self.source is not None:
self.source.disconnectDownstream(self)
-
+ # sources are owned by the Screen, so don't destroy them here.
+ self.destroy()
+
def disconnectDownstream(self, downstream):
self.downstream_elements.remove(downstream)
if self.master == downstream:
def doSuspend(self, suspend):
pass
+
+ def destroy(self):
+ pass