Is NSManagedObjectContext autosaved or am I looking at NSFetchedResultsController's cache?
- by Andreas
I'm developing an iPhone app where I use a NSFetchedResultsController in the main table view controller. I create it like this in the viewDidload of the main table view controller:
NSSortDescriptor *sortDescriptorDate = [[NSSortDescriptor alloc] initWithKey:@"date" ascending:YES];
NSSortDescriptor *sortDescriptorTime = [[NSSortDescriptor alloc] initWithKey:@"start" ascending:YES];
NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptorDate,sortDescriptorTime, nil];
[fetchRequest setSortDescriptors:sortDescriptors];
[sortDescriptorDate release];
[sortDescriptorTime release];
[sortDescriptors release];
controller = [[NSFetchedResultsController alloc]
initWithFetchRequest:fetchRequest
managedObjectContext:context
sectionNameKeyPath:@"date"
cacheName:nil];
[fetchRequest release];
NSError *error;
BOOL success = [controller performFetch:&error];
Then, in a subsequent view, I create a new object on the context:
TestObject *testObject = [NSEntityDescription insertNewObjectForEntityForName:@"TestObject" inManagedObjectContext:context];
The TestObject has several related object which I create in the same way and add to the testObject using the provided add...Objects methods.
Then, if before saving the context, I press cancel and go back to the main table view, nothing is shown as expected. However, if I restart the app, the object I created on the context shows in the main table view. How come? At first, I thought it was because the NSFetchedResultsController was reading from the cache, but as you can see I set this to nil just to test. Also, [context hasChanges] returns true after I restart. What am I missing here?
