not sure why NSFetchedResultsController isn't showing sections - iphone

Question

I previously had a TableView which would get its 2 header views (and separator views) from an array called holdViewsArray in viewDidLoad, like so:
-(void) viewDidLoad{
// ---Start Core Data With NSFetchedResultsController---
[super viewDidLoad];
NSError *error;
if (![[self fetchedResultsController] performFetch:&error]){
NSLog(#"Unresolved error %#, %#", error, [error userInfo]);
exit(-1);
}
// ---End Core Data w/ NSFetchedResultsController---
[self.tableView setDelegate:self];
[self setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
holdViewsArray = [[NSMutableArray alloc]init];
UIView *seperatorView;
UIView *seperatorView2;
NSString *sectionTitle = #"Tasks To Complete";
NSString *section2Title = #"Completed Tasks";
UILabel *label = [[UILabel alloc]init];
UILabel *label2 = [[UILabel alloc]init];
label.frame = CGRectMake(10.0, 5.0, 320.0, 50.0);
label.text = sectionTitle;
label2.frame = CGRectMake(10.0, 0.0, 320.0, 40.0);
label2.text = section2Title;
headerView = [[UIView alloc]initWithFrame:label.frame];
headerView2 = [[UIView alloc]initWithFrame:label2.frame];
CGRect sepFrame = CGRectMake(0, headerView.frame.size.height-2, 320, 1);
CGRect sep2Frame =CGRectMake(0, headerView2.frame.size.height-2, 320, 1);
seperatorView = [[UIView alloc] initWithFrame:sepFrame];
seperatorView2 = [[UIView alloc]initWithFrame:sep2Frame];
[headerView addSubview:seperatorView];
[headerView2 addSubview:seperatorView2];
[headerView addSubview:label];
[headerView addSubview:button];
[headerView2 addSubview:label2];
[holdViewsArray addObject:headerView];
[holdViewsArray addObject:headerView2];
}
After implementing NSFetchedResultsController, I decided that I wanted to use NSFetchedResultsController's properties and methods to make the header views and split the table view into 2 sections. I've tried to do so, but its not giving me any titles in my sections and it just looks awful. How would I keep the same look of the headers that I have now but use NSFetchedResultsController to split the table view into 2 sections (complete and incomplete tasks)? Here is what I tried:
Tasks Core Data property (optional property):
#interface Tasks : NSManagedObject
#property (nonatomic, retain) NSString *sectionString;
#end
#implementation Tasks
#dynamic sectionString;
#end
Adding two tasks in different sections in the App Delegate
NSManagedObjectContext *context = self.managedObjectContext;
NSManagedObject *startingTask = [NSEntityDescription insertNewObjectForEntityForName:#"Tasks" inManagedObjectContext:context];
[startingTask setValue:#"Eat Dinner" forKey:#"taskName"];
[startingTask setValue:[NSNumber numberWithDouble:400] forKey:#"timeInterval"];
[startingTask setValue:#"Tasks To Complete" forKey:#"sectionString"];
NSManagedObject *finishedTask = [NSEntityDescription insertNewObjectForEntityForName:#"Tasks" inManagedObjectContext:context];
[finishedTask setValue:#"Do Laundry" forKey:#"taskName"];
[finishedTask setValue:[NSNumber numberWithDouble:400] forKey:#"timeInterval"];
[finishedTask setValue:#"Completed Tasks" forKey:#"sectionString"];
NSError *error;
if (![context save:&error]) {
NSLog(#"couldn't save: %#", [error localizedDescription]);
}
Splitting into two sections
- (NSFetchedResultsController *)fetchedResultsController {
if (_fetchedResultsController != nil) {
return _fetchedResultsController;
}
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription
entityForName:#"Tasks" inManagedObjectContext:managedObjectContext];
[fetchRequest setEntity:entity];
NSSortDescriptor *isCompleted = [[NSSortDescriptor alloc]initWithKey:#"sectionString" ascending:NO];
NSSortDescriptor *sort = [[NSSortDescriptor alloc]
initWithKey:#"dateCreated" ascending:NO];
[fetchRequest setSortDescriptors:#[isCompleted, sort]];
[fetchRequest setFetchBatchSize:20];
NSFetchedResultsController *theFetchedResultsController =
[[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest
managedObjectContext:managedObjectContext sectionNameKeyPath:#"sectionString"
cacheName:#"Root"];
self.fetchedResultsController = theFetchedResultsController;
_fetchedResultsController.delegate = self;
return _fetchedResultsController;
}
What am I doing wrong that's causing it to not split into 2 sections with titles of "Tasks To Complete" and "Completed Tasks"?