Question

I have a core data entity called “TruckNumber” which has a string as it’s only property. The string is usually a 1-3 digit integer (as a string) but sometimes can have letters such as TMP9. The name of the property is “itsNotANumma”. I am doing a fetch request to populate a picker, but they are not being sorted and I don’t know why. I’ve used this exact technique on other entities for other pickers and never had a problem. Please help… Here’s the relevant code:

// Fetch truck numbers
NSFetchRequest *truckNumberFetchRequest = [[NSFetchRequest alloc] init];

NSEntityDescription *truckEntity = [NSEntityDescription entityForName:@"TruckNumber" inManagedObjectContext:self.managedObjectContext];
[truckNumberFetchRequest setEntity:truckEntity];

// Sort Descriptor
NSSortDescriptor *truckDescriptor = [[NSSortDescriptor alloc] initWithKey:@"itsNotANumma" ascending:YES];

NSArray *truckSortDescriptors = [[NSArray alloc] initWithObjects:truckDescriptor, nil];
[inventoryFetchRequest setSortDescriptors:truckSortDescriptors];
error = nil;
NSArray *truckResults = [managedObjectContext executeFetchRequest:truckNumberFetchRequest error:&error];

if (error)
    NSLog(@"Unresolved error while saving context: %@, %@", error, [error userInfo]);

truckNumbersArray = [[NSMutableArray alloc] init];
for (TruckNumber *truckNumber in truckResults)
{
    [truckNumbersArray addObject:truckNumber.itsNotANumma];
}

Here is my data model for truck number:

These are the results:

Answer 1

Looks like you have a simple typo:

[inventoryFetchRequest setSortDescriptors:truckSortDescriptors];

Should be:

[truckNumberFetchRequest setSortDescriptors:truckSortDescriptors];

I would assume anyway, from reading that code.