ios,objective-c,xcode,core-data,nsmanagedobjectid
You have some problems you aren't aware of. Primarily, you shouldn't be storing passwords in core data because it isn't secure. Also, when you set a predicate on a fetch request it replaces any existing predicate so your login check only looks at the password, not the email address (because...
ios,objective-c,nsmanagedobjectid
The problem you are having is that for objects to be properly stored in a dictionary and then serialized to disk they must be NSCoding compliant which NSManagedObjectID is not. Fortunately there is another way. There is a method on an NSManagedObjectID called URIRepresentation which will be you an identifier...