Comparison function for Core Data NSFetchedResultsController

Question

I am using NSFetchedResultsController to section my data into separate sections. The main sortDescriptor I give is this:

NSSortDescriptor *sortDescriptorSectionLetter = [[NSSortDescriptor alloc] initWithKey:@"sectionLetter" ascending:YES selector:@selector(localizedCompare:)];

Now my sectionLetter has a default value of "#". When the tableView is sectioned and presented, it places the '#' section at the top of the table. I want this to show up at the bottom of the list (like the Contacts app does it). But I can't figure out how to accomplish this.

I've also tried different types of characters as the default instead of #, like � and ~, but this doesn't seem to work either. According to the Core Data Programming Guide, I can't pass in a customized comparison function here.

So I'm not sure what my options are here (other than doing the sectioning myself and losing all the FRC delegate goodness to reload my tableviews with animation). Any good ideas?

Answer 1

Notice the remark in the documentation for NSFetchedResultsController:

Subclassing Notes
You create a subclass of this class if you want to customize the creation of sections and index titles. You override sectionIndexTitleForSectionName: if you want the section index title to be something other than the capitalized first letter of the section name. You override sectionIndexTitles if you want the index titles to be something other than the array created by calling sectionIndexTitleForSectionName: on all the known sections.