Getting back an Object
gherron at islandtraining.com
Fri Mar 28 06:29:13 CET 2008
David Anderson wrote:
> Well, I've got a little problem, I have a list that contains objects
> from the class C, then I use those objects.__str__ to generate a
> ListCtrl, A wxPython widget that makes a list of strings and then you
> can handle events when selected, and returns the string selcted, how
> can I access the "parent" of that string?
> I tried to search on the array like this:
> def search(self, string):
> for obj in self.list:
> if string == obj.__str__:
> return obj
> return None
> But I always get None... What am I doing wrong?
Once again, you are confused over the difference between a value and a
function that, when called, returns a value.
obj.__str__ is a function.
If you call it like this, obj.__str__(), then you get a string.
So your comparison should be
if string == obj.__str__():
Slightly better would be to call
and let Python translate that into a call to __str__.
But even better is to replace this rather bogus approach with something
better. When you create an object, record its string representation in
a dictionary to be used to recover the object when given a string later:
That is, for each object obj do:
objMap[str(obj)] = obj
and later with the string in hand, do
obj = objMap[string]
One other word of warning. It is best to not use a variable named
"string" as Python has a builtin type of that name which would become
inaccessible if you redefine.
More information about the Python-list