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POMysterious core data behavior retrieves empty objects on second fetch
 

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  1. POMysterious core data behavior retrieves empty objects on second fetch
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    <p>I'm trying to display a list of objects from Core Data into a UITableViewController. Here is the viewWillAppear of this UITableViewController:</p> <pre><code>- (void)viewWillAppear:(BOOL)animated{ [super viewWillAppear:animated]; self.landmarks = [[TSDataManager sharedInstance] fetchArrayFromDBWithEntity:@"Landmark" forKey:nil withPredicate:nil]; [self.tableView reloadData]; } </code></pre> <p>And here is the fetchArrayFromDBWithEntity:forKey:withPredicate: implementation:</p> <pre><code>- (NSMutableArray*)fetchArrayFromDBWithEntity:(NSString*)entityName forKey:(NSString*)keyName withPredicate:(NSPredicate*)predicate { NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:entityName inManagedObjectContext:self.managedObjectContext]; [request setEntity:entity]; if(keyName != nil){ NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:keyName ascending:NO]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [request setSortDescriptors:sortDescriptors]; } if (predicate != nil){ [request setPredicate:predicate]; } NSError *error = nil; NSMutableArray *mutableFetchResults = [[self.managedObjectContext executeFetchRequest:request error:&amp;error] mutableCopy]; if (mutableFetchResults == nil) { NSLog(@"%@", error); } return mutableFetchResults; } </code></pre> <p>When the table first appears, everything is displayed correctly, I have 4 objects coming back from the DB with titles that are correctly displayed in each cell.</p> <p>But whenever I go to another view and come back, the table has four objects alright, but the value of their "title" property is nil!</p> <p>Here is the code of my Landmark class:</p> <pre><code>@interface Landmark : NSManagedObject @property (nonatomic, strong) NSString * title; @end @implementation Landmark @dynamic title; @end </code></pre> <p>And here is how my table cells are constructed, in case it comes from there:</p> <pre><code>- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"LandmarkCell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath]; Landmark *landmark = (Landmark *) self.landmarks[(NSUInteger) indexPath.row]; cell.textLabel.text = landmark.title; return cell; } </code></pre> <p>Obviously I'm doing something wrong here, but I seriously can't figure out what.</p>
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    1. USSebastien
    1. USSebastien
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      1. This table or related slice is empty.
      1. VTUpMod
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    1. COAre you absolutely positive that the property is using dynamic for it's properties? I had the same problem awhile back due to using synthesize instead of dynamic.
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      1. USBiclops
 

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