NSetchedResultsController TableView subclass

CDTableViewController.h

#import <UIKit/UIKit.h>


@interface CDTableViewController : UITableViewController <NSFetchedResultsControllerDelegate> {
    NSFetchedResultsController *fetchedResultsController_;
}

@property (nonatomic, retain) NSFetchedResultsController *fetchedResultsController;

- (void)reloadData;
- (void)configureCell:(UITableViewCell *)cell atIndexPath:(NSIndexPath *)indexPath;

@end

CDTableViewController.m

#import "CDTableViewController.h"

@implementation CDTableViewController

@synthesize fetchedResultsController = fetchedResultsController_;

- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    
    fetchedResultsController_.delegate = nil;
    fetchedResultsController_ = nil;
    /*
    self.fetchedResultsController.delegate = nil;
    self.fetchedResultsController = nil;
     */
    [super dealloc];
}

- (void)didReceiveMemoryWarning
{
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];
    
    // Release any cached data, images, etc that aren't in use.
}

#pragma mark - View lifecycle

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Uncomment the following line to preserve selection between presentations.
    self.clearsSelectionOnViewWillAppear = YES;
 
    // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
    // self.navigationItem.rightBarButtonItem = self.editButtonItem;
}

- (void)viewDidUnload
{
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
}

- (void)viewDidDisappear:(BOOL)animated
{
    [super viewDidDisappear:animated];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    // Return YES for supported orientations
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return [[self.fetchedResultsController sections] count];
}


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    id <NSFetchedResultsSectionInfo> sectionInfo = [[self.fetchedResultsController sections] objectAtIndex:section];
    NSInteger num = [sectionInfo numberOfObjects];
    //NSLog(@"numberOfRowsInSection %d : %d", section, num);
    return num;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
    return [[[self.fetchedResultsController sections] objectAtIndex:section] name];
}

- (void)configureCell:(UITableViewCell *)cell atIndexPath:(NSIndexPath *)indexPath
{
    
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    }
    
    // Configure the cell...
    [self configureCell:cell atIndexPath:indexPath];
    
    return cell;
}

/*
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the specified item to be editable.
    return YES;
}
*/

/*
// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        // Delete the row from the data source
        [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
    }   
    else if (editingStyle == UITableViewCellEditingStyleInsert) {
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
    }   
}
*/

/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
}
*/

/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the item to be re-orderable.
    return YES;
}
*/

#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Navigation logic may go here. Create and push another view controller.
    /*
     <#DetailViewController#> *detailViewController = [[<#DetailViewController#> alloc] initWithNibName:@"<#Nib name#>" bundle:nil];
     // ...
     // Pass the selected object to the new view controller.
     [self.navigationController pushViewController:detailViewController animated:YES];
     [detailViewController release];
     */
}

#pragma mark - Fetched results controller

- (NSFetchedResultsController *)fetchedResultsController {
    
    if (fetchedResultsController_) {
        return fetchedResultsController_;
    }
    
    return fetchedResultsController_;
} 

- (void)reloadData {
    
    NSError *error;
    if (![self.fetchedResultsController performFetch:&error]) {
        NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
    }
}

#pragma mark - Fetched results controller delegate

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller {
    [self.tableView beginUpdates];
}

- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject
       atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type
      newIndexPath:(NSIndexPath *)newIndexPath {
    
    UITableView *tableView = self.tableView;
    
    switch(type) {
            
        case NSFetchedResultsChangeInsert:
            [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;
            
        case NSFetchedResultsChangeDelete:
            [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;
            
        case NSFetchedResultsChangeUpdate:
            [self configureCell:[tableView cellForRowAtIndexPath:indexPath] atIndexPath:indexPath];
            break;
            
        case NSFetchedResultsChangeMove:
            [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            // Reloading the section inserts a new row and ensures that titles are updated appropriately.
            //[tableView reloadSections:[NSIndexSet indexSetWithIndex:newIndexPath.section] withRowAnimation:UITableViewRowAnimationFade];
            [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath]withRowAnimation:UITableViewRowAnimationFade];
            break;
    }
}

- (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id <NSFetchedResultsSectionInfo>)sectionInfo atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type {
    
    UITableView *tableView = self.tableView;
    
    switch(type) {
        case NSFetchedResultsChangeInsert:
            [tableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
            break;
            
        case NSFetchedResultsChangeDelete:
            [tableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
            break;
    }
}


- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller {
    [self.tableView endUpdates];
}

@end

gistfile1.m

#pragma mark - View lifecycle

- (void)viewDidLoad
{
    [super viewDidLoad];

    [self reloadData];
}

#pragma mark - Table view data source

- (void)configureCell:(UITableViewCell *)cell atIndexPath:(NSIndexPath *)indexPath
{
    FoodCategory *category = (id)[self.fetchedResultsController objectAtIndexPath:indexPath];
    cell.textLabel.text = category.name;
}

#pragma mark - Fetched results controller

- (NSFetchedResultsController *)fetchedResultsController {
    
    if (fetchedResultsController_) {
        return fetchedResultsController_;
    }
    
    
    NSManagedObjectContext *moc = [[RKObjectManager sharedManager].objectStore managedObjectContext];
    
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"FoodCategory" inManagedObjectContext:moc];
    [fetchRequest setEntity:entity];
    
    //[fetchRequest setPredicate:[NSPredicate predicateWithFormat:@"provider == %@", self.provider]];
	
    //[fetchRequest setFetchLimit:9];
    [fetchRequest setFetchBatchSize:20];
    
    // Edit the sort key as appropriate.
    NSSortDescriptor *sort = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:NO];
    [fetchRequest setSortDescriptors:[NSArray arrayWithObjects:sort, nil]];
	
    //[NSFetchedResultsController deleteCacheWithName:@"Products"];
    
    NSFetchedResultsController *theFetchedResultsController = 
    [[NSFetchedResultsController alloc]
     initWithFetchRequest:fetchRequest
     managedObjectContext:moc
     sectionNameKeyPath:nil
     cacheName:@"foodCategories"];
    
    self.fetchedResultsController = theFetchedResultsController;
    fetchedResultsController_.delegate = self;
    
    [sort release];
    [fetchRequest release];
    [theFetchedResultsController release];
    
    
    return fetchedResultsController_;
}