NSFetchController fetch with other predicate when 1ste one fails - ios

Question

I'm having a fetchrequest. Now I need to get "tracked" points from the database but when there are no tracked points they all need to be retrieved.
How can I do that? I now set a predicate on my fetchcontroller but when it doesn't find any tracked points it just doesn't show anything. So where can I hook up on this and then say retrieve everything...
Is there a way to listen that there is nothing found or how is this done?
EDIT:
- (NSFetchedResultsController *)fetchedResultsController {
if (_fetchedResultsController != nil) {
return _fetchedResultsController;
}
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:#"Rank" inManagedObjectContext:[NSManagedObjectContext MR_defaultContext]];
[fetchRequest setEntity:entity];
/* NSPredicate *predicate = [NSPredicate predicateWithFormat:#"name == %#", #"Auto"];
[fetchRequest setPredicate:predicate];*/
NSSortDescriptor *sort = [[NSSortDescriptor alloc] initWithKey:#"name" ascending:NO];
[fetchRequest setSortDescriptors:#[sort]];
[fetchRequest setFetchBatchSize:20];
NSFetchedResultsController *theFetchedResultsController =
[[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest
managedObjectContext:[NSManagedObjectContext MR_defaultContext] sectionNameKeyPath:nil
cacheName:nil];
self.fetchedResultsController = theFetchedResultsController;
_fetchedResultsController.delegate = self;
return _fetchedResultsController;
}

Answer 1

Thanks to Larme this is the solution:
- (NSFetchedResultsController *)fetchedResultsController {
if (_fetchedResultsController != nil) {
return _fetchedResultsController;
}
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:#"Rank" inManagedObjectContext:[NSManagedObjectContext MR_defaultContext]];
[fetchRequest setEntity:entity];
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"name == %#", #"DON"];
[fetchRequest setPredicate:predicate];
NSSortDescriptor *sort = [[NSSortDescriptor alloc] initWithKey:#"name" ascending:NO];
[fetchRequest setSortDescriptors:#[sort]];
[fetchRequest setFetchBatchSize:20];
NSFetchedResultsController *theFetchedResultsController =
[[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest
managedObjectContext:[NSManagedObjectContext MR_defaultContext] sectionNameKeyPath:nil
cacheName:nil];
self.fetchedResultsController = theFetchedResultsController;
_fetchedResultsController.delegate = self;
if ([[_fetchedResultsController fetchedObjects] count] == 0)
{
NSLog(#"0 found");
[fetchRequest setPredicate:nil];
}
return _fetchedResultsController;
}