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PONot getting data from Core Data
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copied!<p>I am using Core Data to store some information for my app. I have a .xcdatamodeld file containing 8 entities, and I extract them on different views.</p> <p>In one of the viewControllers, I call three of them. Like this:</p> <pre><code> AppDelegate *appDelegate = (AppDelegate *) [[UIApplication sharedApplication]delegate]; managedObjectContext = appDelegate.managedObjectContext; NSManagedObjectContext *moc = [self managedObjectContext]; NSEntityDescription *entiAll = [NSEntityDescription entityForName:@"AllWeapons" inManagedObjectContext:moc]; NSFetchRequest *frAll = [[NSFetchRequest alloc] init]; [frAll setEntity:entiAll]; NSError *error = nil; arrAll = [moc executeFetchRequest:frAll error:&error]; displayArray = [[NSMutableArray alloc]initWithArray:arrAll]; NSEntityDescription *entiRange = [NSEntityDescription entityForName:@"WeaponsRanged" inManagedObjectContext:moc]; NSFetchRequest *frRanged = [[NSFetchRequest alloc] init]; [frRanged setEntity:entiRange]; NSError *errorRanged = nil; arrRange = [moc executeFetchRequest:frRanged error:&errorRanged]; NSLog(@"%i, %i", [arrRange count], [[moc executeFetchRequest:frRanged error:&errorRanged] count]); NSEntityDescription *entiMelee = [NSEntityDescription entityForName:@"WeaponsMelee" inManagedObjectContext:moc]; NSFetchRequest *frMelee = [[NSFetchRequest alloc] init]; [frMelee setEntity:entiMelee]; NSError *errorMelee = nil; arrMelee = [moc executeFetchRequest:frMelee error:&errorMelee]; NSLog(@"%i, %i", [arrMelee count], [[moc executeFetchRequest:frMelee error:&errorMelee] count]); </code></pre> <p>The problem is that the middle one (the one filling the arrRange-array) doesn't work..</p> <p>arrAll logs out with all correct data, arrMelee logs out with all the correct data (x4 for some reason, don't know if this is related :S), but arrRange logs out as an empty array. <code>[arrRange count];</code> gives me 0, even though I know there is lots of data there. I ran this code on the simulator, and found the .sqlite file, opened it in Firefox's SQLite Manager, and saw the correct data, 40 rows.</p> <p>I went into the appDelegate, where I fill the CoreData when necessary, and saw that the method which downloads the data in JSON-format successfully sends it to the sqlite aswell.</p> <p>Here I fill the CoreData with data from the json:</p> <pre><code>[self deleteAllObjects:@"WeaponsRanged"]; NSManagedObjectContext *context = [self managedObjectContext]; for(NSDictionary *item in jsonWeaponRanged) { WeaponsRanged *wr = [NSEntityDescription insertNewObjectForEntityForName:@"WeaponsRanged" inManagedObjectContext:context]; ///***/// wr.recoil = [item objectForKey:@"Recoil"]; ///***/// NSError *error; if(![context save:&error]) NSLog(@"%@", [error localizedDescription]); } </code></pre> <p>And if I here do <code>NSLog(@"%@ - %@", wr.recoil, [item objectForKey:@"Recoil"]);</code> I get the correct data. (Same data on both)</p> <p>So. The correct data is obviously in the core. But my NSFetchRequest or something is failing. I am pretty noob at Objective-C, so it might be my bad code-grammar striking again. I realize I should use things again etc, not creating new objects all the time.. But cmon, this is my first app.. And if that is actually the problem, I might learn. But I'm stuck.</p> <p>SOMETIMES I get data, sometimes I don't. It's weird. I re-launched the app, and got data from it, and now I don't.. I haven't found a pattern yet..</p> <p>Anyone? Or is there another way to request data from the entity?</p>

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