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POFetch relationships and show in a UITableView
 

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    <p>I have the following relationship set up in my Core Data model, in my shopping cart app. </p> <p><code>Menu</code> ->> <code>Product</code> &lt;&lt;- <code>Cart</code> (See picture below).</p> <p><img src="https://i.stack.imgur.com/lqcPS.png" alt="enter image description here"></p> <p>And a Objective-C category with the following code:</p> <pre><code>+ (Cart *)addProductToCartWithProduct:(Product *)product inManagedObjectContext:(NSManagedObjectContext *)context { Cart *cart = [NSEntityDescription insertNewObjectForEntityForName:@"Cart" inManagedObjectContext:context]; NSManagedObjectID *retID = [product objectID]; [(Product *)[context objectWithID:retID] setInCart:cart]; [cart addProductsObject:(Product *)[context objectWithID:retID]]; return cart; } </code></pre> <p>When the user pushes the "add to cart" button in the app, this method is fired (the method above). I now want to fetch these products (which is added to the cart by the user), in my other class, where the "cart" is located. I want these products to be shown in my <code>UITableView</code> in that class, I therefore use an FRC. <em>But I can't figure out how to fetch the relationship and thereby show the products. How would I manage to do this?</em></p> <p>I have the following code right now.</p> <pre><code>- (void)loadCart { NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; fetchRequest.entity = [NSEntityDescription entityForName:@"Cart" inManagedObjectContext:_theManagedObjectContext]; NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"id" ascending:YES]; fetchRequest.sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [NSFetchedResultsController deleteCacheWithName:@"cartproducts"]; self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:_theManagedObjectContext sectionNameKeyPath:nil cacheName:@"cartproducts"]; _fetchedResultsController.delegate = self; NSError *error = nil; if (![_fetchedResultsController performFetch:&amp;error]) { NSLog(@"Fetch Failed"); } } </code></pre> <p>My <code>UITableview</code> <code>cellForRowAtIndexPath:</code> method.</p> <pre><code>- (UITableViewCell *)tableView:(UITableView *)aTableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *plainCellIdentifier = @"OrderCell"; ProductsCell *cell = (ProductsCell *)[aTableView dequeueReusableCellWithIdentifier:plainCellIdentifier]; if (!cell) { cell = [[ProductsCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:plainCellIdentifier]; } Cart *ret = (Cart *)[self.fetchedResultsController objectAtIndexPath:indexPath]; // How to show the product names using the relationship? cell.title = ret.products ??; [cell setNeedsDisplay]; return cell; } </code></pre>
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    1. USLorenzo B
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      1. USWeekendCodeWarrior
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    1. COSo you want to display the products for one specific cart?
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      1. USMartin R
    2. COYes, I only have one cart in my app. Is this possible? :)
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      1. US7c9d6b001a87e497d6b96fbd4c6fdf
 

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