Can I use NSFetchedResultsController for the display of data not meant for a UITableView?
In the FRC documentation, it says that it is intended to efficiently manage the results returned from a Core Data fetch request to provide data for a UITableView object.
I am trying to setup my Core Data stack to handle the storage and retrieval of some VERY basic data. Can I not use FRC? I need to display a value set in the db to a UILabel, what is the best Core Data method to use for that?
I have a core data book I am trying to get thro开发者_JS百科ugh, but the going is rough, so any help here would go a long way. Thanks!!
NSFetchedResultsController may be overkill if all you want is to fetch an object and display one of its attributes in UILabel. Take a look at NSFetchRequest and start with something like this:
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
[fetchRequest setEntity:[NSEntityDescription entityForName:entityDescription
inManagedObjectContext:managedObjectContext]];
NSPredicate *predicate = /* define predicate here */;
[fetchReqest setPredicate:predicate];
NSError *error = nil;
NSArray *results = [managedObjectContext executeFetchRequest:fetchRequest error:&error];
[fetchRequest release];
If you want to sort your results, read up on NSSortDescriptor. You will need to set sort descriptors prior to -executeFetchRequest: call.
Your results will be in 'results' array - and they should include NSManagedObjects that you can get attribute values from.
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