I tried to subclass NSKeyedUnarchiver because I want to add some instance
variables, e.g. a "doent version".
There is no chance to extend the class by overriding
"unarchiveObjectWithData" because this method is a class method (there are
no instance variables at this point). So I tried it with
"initForReadingWithData". I wrote a subclass of NSKeyedUnarchiver, e.g.
named MyUnarchiver, and added a method e.g.
"initForReadingWithData:myExtensions:..." where I can add some parameters
(e.g. doent version) that are then stored as instance variables in my
Then I replaced my previous decoding code:
myObject = [[NSKeyedUnarchiver unarchiveObjectWithData:data] retain];
with this new ...