Sorting toMany relationship Set in core data

core-data, iphone

Solution

Minor improvement over Adrian Hosey's code:

Instead of manually iterating over all workers you can also just do:

-(NSArray *)sortedWorkers {
  NSSortDescriptor *sortNameDescriptor = [[[NSSortDescriptor alloc] initWithKey:@"firstName" ascending:YES] autorelease];
  NSArray *sortDescriptors = [[[NSArray alloc] initWithObjects:sortNameDescriptor, nil] autorelease];

  return [self.workers sortedArrayUsingDescriptors:sortDescriptors];
}

Probably does exactly the same thing as your iteration internally, but maybe they made it more efficient somehow. It's certainly less typing…

Note: the above only works on iOS 4.0+ and OSX 10.6+. In older versions you need to replace the last line with:

  return [[self.workers allObjects] sortedArrayUsingDescriptors:sortDescriptors];

Problem

I have Two models Department and Worker. Departments has to-many relationship(workers) to worker. Worker has firstName field. How can i get a worker list sorted by firstName by accessing departmet.workers? Is there any way to add sort descriptors in to-many relationship?

Original source