TableView FetchedResultsController

DataSource.h

#import <Foundation/Foundation.h>
#import <CoreData/CoreData.h>

@interface DXListTableViewDataSource : NSObject <UITableViewDataSource>

@property (nonatomic, strong) NSFetchedResultsController *fetchedResultsController;

- (void)registerTableView:(UITableView *)tableView;
- (void)configureFetchedResultsControllerForTableView:(UITableView *)tableView;

@end

DataSource.m

#import "DXListTableViewDataSource.h"
#import "EntryController.h"
#import "Stack.h"

@interface DXListTableViewDataSource() <NSFetchedResultsControllerDelegate>

@property (nonatomic, strong) UITableView* tableView;

@end

@implementation DXListTableViewDataSource

- (void)registerTableView:(UITableView *)tableView {
    [tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:NSStringFromClass([UITableViewCell class])];
    self.tableView = tableView;
}

- (void)configureFetchedResultsControllerForTableView:(UITableView *)tableView {
    NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:@"Entry"];
    fetchRequest.sortDescriptors = @[[NSSortDescriptor sortDescriptorWithKey:@"timestamp" ascending:NO]];
    self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:[Stack sharedInstance].managedObjectContext sectionNameKeyPath:nil cacheName:nil];
    self.fetchedResultsController.delegate = self;
    [self.fetchedResultsController performFetch:nil];
    self.tableView = tableView;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return self.fetchedResultsController.fetchedObjects.count;
}


- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:NSStringFromClass([UITableViewCell class])];
    
    Entry *entry = self.fetchedResultsController.fetchedObjects[indexPath.row];
    cell.textLabel.text = entry.title;
    
    return cell;
}

#pragma mark - Fetched Results Controller Delegate

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

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

- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type newIndexPath:(NSIndexPath *)newIndexPath {
    switch (type) {
        case NSFetchedResultsChangeInsert:
            [self.tableView insertRowsAtIndexPaths:@[newIndexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
            break;
        case NSFetchedResultsChangeMove:
            [self.tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
            [self.tableView insertRowsAtIndexPaths:@[newIndexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
            break;
        case NSFetchedResultsChangeDelete:
            [self.tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;
        case NSFetchedResultsChangeUpdate:
            [self.tableView reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
            break;
        default:
            break;
    }
}

@end