StoreMad/SMTableViewDataSource.m

//
//  SMTableViewDataSource.m
//  StoreMad
//
//  Created by Andrew Smith on 10/4/12.
//  Copyright (c) 2012 Andrew B. Smith ( http://github.com/drewsmits ). All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
// of the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

#import "SMTableViewDataSource.h"

@interface  SMTableViewDataSource ()

@property (nonatomic, weak) UITableView *tableView;

@end

@implementation SMTableViewDataSource

- (void)setupWithTableView:(UITableView *)tableView
              fetchRequest:(NSFetchRequest *)fetchRequest
                   context:(NSManagedObjectContext *)context
        sectionNameKeyPath:(NSString *)sectionNameKeyPath
                 cacheName:(NSString *)cacheName
{
    self.tableView = tableView;
    
    // Normal setup
    [self setupWithFetchRequest:fetchRequest
                        context:context
             sectionNameKeyPath:sectionNameKeyPath
                      cacheName:cacheName];
}

#pragma mark - NSFetchedResultsControllerDelegate

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller
{
    [self.tableView beginUpdates];
    
    // Update sections
    for (NSInteger i = self.tableView.numberOfSections; i < controller.sections.count; i++) {
        [self.tableView insertSections:[NSIndexSet indexSetWithIndex:i]
                      withRowAnimation:UITableViewRowAnimationAutomatic];
    }
}

- (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 NSFetchedResultsChangeDelete:
            [self.tableView deleteRowsAtIndexPaths:@[indexPath]
                                  withRowAnimation:UITableViewRowAnimationAutomatic];
            break;
        case NSFetchedResultsChangeUpdate:
            // If you call reload here, you can run into a Core Data crash,
            // where you see [__NSArrayM insertObject:atIndex:]: object cannot be nil.
            // To be honest, I'm not sure what this is, could be a bug.
//            [self.tableView reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationNone];
            
            // Instead, you can just re-configure the cell at the index path, which
            // does the same thing.
            [self.dataSourceDelegate configureCell:[self.tableView cellForRowAtIndexPath:indexPath]
                                       atIndexPath:indexPath];
            break;
        case NSFetchedResultsChangeMove:
            [self.tableView moveRowAtIndexPath:indexPath
                                   toIndexPath:newIndexPath];
            break;
    }
}

- (void)controller:(NSFetchedResultsController *)controller
  didChangeSection:(id)sectionInfo
           atIndex:(NSUInteger)sectionIndex
     forChangeType:(NSFetchedResultsChangeType)type
{
    switch(type) {
        case NSFetchedResultsChangeInsert:
            [self.tableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex]
                          withRowAnimation:UITableViewRowAnimationAutomatic];
            break;
        case NSFetchedResultsChangeDelete:
            [self.tableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex]
                          withRowAnimation:UITableViewRowAnimationAutomatic];
            break;
        case NSFetchedResultsChangeMove:
            break;
        case NSFetchedResultsChangeUpdate:
            break;
        default:
            break;
    }
}

- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller
{
    [self.tableView endUpdates];
    
    if ([self.dataSourceDelegate respondsToSelector:@selector(fetchResultsDidChange)]) {
        [self.dataSourceDelegate performSelector:@selector(fetchResultsDidChange)];
    }
}

@end