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POUpdating UITableView (NSFetchedResultsControllerDelegate) from background thread using notifications
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copied!<p>I have a UITableView set up as a NSFetchedResultsControllerDelegate. I have a background thread getting data (in a separate managedObjectContext). Both contexts share the same store coordinator. When an object is removed from the background context (after save) I get the following error:</p> <blockquote> <p>An exception was caught from the delegate of NSFetchedResultsController during a call to -controllerDidChangeContent:. <em>*</em> -[NSMutableArray removeObjectAtIndex:]: index 0 beyond bounds for empty array with userInfo (null)</p> </blockquote> <p>I'm adding an observer on the background thread like this:</p> <pre><code> [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(didsave:) name:NSManagedObjectContextDidSaveNotification object:[self managedObjectContext]]; </code></pre> <p>and my didsave: implementation is the following:</p> <pre><code> -(void)didsave:(NSNotification *)nofication { MyAppDelegate *myApp = (MyAppDelegate*)[[UIApplication sharedApplication] delegate]; NSManagedObjectContext *mainContext = [myApp managedObjectContext]; [mainContext performSelectorOnMainThread:@selector(mergeChangesFromContextDidSaveNotification:) withObject:nofication waitUntilDone:YES]; } </code></pre> <p>In the UITableView controller from didChangeContent:</p> <pre><code>case NSFetchedResultsChangeDelete: [self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade]; break; </code></pre> <p>Cannot I mix a fetchControllerDelegate and another background MOcontext, like I'm trying to do?</p>

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