Question

I have a Core Data project with a sort of “master” entity that holds a year value (int 16) and a few other values. There are a few other “child” entities with many-to-one relationships to this one master. In one of those other entities, I want to set a couple of default values, which are a start and end date. The default values should be the beginning and end of the year assigned to the master entity. So I’ve used this:

- (void) awakeFromInsert {
    int currentYear = [[self valueForKeyPath: @"master.year"] intValue];
    NSString *currentYearStart = [NSString stringWithFormat: @"%d-01-01 00:00:01 +0000", currentYear];
    NSString *currentYearEnd = [NSString stringWithFormat: @"%d-12-31 23:59:59 +0000", currentYear];
    [self setStartDate: [NSDate dateWithString: currentYearStart]];
    [self setEndDate: [NSDate dateWithString: currentYearEnd]];    
}

When I run this, currentYear always ends up being 0, even though the value of master’s “year” attribute is 2011. I’ve tried setting “int currentYear = 2011” and then the code works as expected, so the problem seems to be in the first line. The strange thing is, inside the master entity’s subclass of NSManagedObject, I have lines like:

float total = [[self valueForKeyPath: @"[e-mail]"] floatValue];

and this always returns the right amount. I don’t see what the difference is. Can anyone else?

Answer 1

Are you sure that master is set at the time your method is called? Also, the awakeFromInsert docs indicate that you must call [super awakeFromInsert] first.