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    <p>I added this functionality to my detail view. My entity has a "favorite" attribute. Pressing the "favorite" button in the detail view sets a string for the favorite attribute and toggles a star image on and off:</p> <pre><code>- (IBAction)flagButtonPressed:(id)sender { if (flagButtonSelected == 0) { [flagButton setSelected:YES]; flagButtonSelected = 1; [flagButtonImage setImage:[UIImage imageNamed:@"yesFavorite.png"]]; [myCoolEntity setValue:@"yesFlag" forKey:@"flagSet"]; } else { [flagButton setSelected:NO]; flagButtonSelected = 0; [flagButtonImage setImage:[UIImage imageNamed:@"noFavorite.png"]]; [myCoolEntity setValue:@"noFlag" forKey:@"flagSet"]; } NSManagedObjectContext *context = myCoolEntity.managedObjectContext; NSError *error = nil; if (![context save:&amp;error]) { NSLog(@"Tried to save fav. Unresolved error %@, %@", error, [error userInfo]); abort(); } } </code></pre> <p>Then back in my main table view, I have a favorites button in the nav bar that pushes a new view controller with a NSFetchedResultsController and predicate that looks for all the entities that have the "flagSet" attribute set to "yesFlag".</p> <pre><code>- (NSFetchedResultsController *)fetchedResultsController { // Set up the fetched results controller if needed. if (fetchedResultsController == nil) { // Create the fetch request for the entity. NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; // Edit the entity name as appropriate. NSEntityDescription *entity = [NSEntityDescription entityForName:@"MyCoolEntity" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; NSPredicate *predicate = [NSPredicate predicateWithFormat: @"flagSet like 'yesFlag'"]; [fetchRequest setPredicate:predicate]; //set batch size [fetchRequest setFetchBatchSize:20]; // Edit the sort key as appropriate. NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [fetchRequest setSortDescriptors:sortDescriptors]; // Edit the section name key path and cache name if appropriate. // nil for section name key path means "no sections". NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:managedObjectContext sectionNameKeyPath:@"name" cacheName:nil]; aFetchedResultsController.delegate = self; self.fetchedResultsController = aFetchedResultsController; [aFetchedResultsController release]; [fetchRequest release]; [sortDescriptor release]; [sortDescriptors release]; } return fetchedResultsController; } </code></pre> <p>Also, in viewDidLoad for the detail view I display the star image on the favorites button as appropriate:</p> <pre><code>//flag button if ([myCoolEntity.flagSet isEqual:@"yesFlag"]) { [flagButtonImage setImage:[UIImage imageNamed:@"yesFavorite.png"]]; [flagButton setSelected:YES]; flagButtonSelected = 1; } else { [flagButtonImage setImage:[UIImage imageNamed:@"noFavorite.png"]]; [flagButton setSelected:NO]; flagButtonSelected = 0; } </code></pre>
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    1. POcore data for 'add to favorites' button?
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    1. USRyeMAC3
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    1. COThis is just what I have thought about doing, thanks for this great example, been looking all over www for it.
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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