Why is a CoreData forceFetch required after a delete on the iPad but not the iPhone?
- by alyoshak
When the following code is run on the iPhone the count of fetched objects after the delete is one less than before the delete. But on the iPad the count remains the same. This inconsistency was causing a crash on the iPad because elsewhere in the code, soon after the delete, fetchedObjects is called and the calling code, trusting the count, attempts access to the just-deleted object's properties, resulting in a NSObjectInaccessibleException error (see below). A fix has been to use that commented-out call to performFetch, which when executed makes the second call to fetchObjects yield the same result as on the iPhone without it. My question is: Why is the iPad producing different results than the iPhone? This is the second of these differences that I've discovered and posted recently.
-(NSError*)deleteObject:(NSManagedObject*)mo;
{
NSLog(@"\n\nNum objects in store before delete: %i\n\n",
[[self.fetchedResultsController fetchedObjects] count]);
[self.managedObjectContext deleteObject:mo];
// Save the context.
NSError *error = nil;
if (![self.managedObjectContext save:&error]) {
}
// [self.fetchedResultsController performFetch:&error]; // force a fetch
NSLog(@"\n\nNum objects in store after delete (and save): %i\n\n",
[[self.fetchedResultsController fetchedObjects] count]);
return error;
}
(The full NSObjectInaccessibleException is: "Terminating app due to uncaught
exception 'NSObjectInaccessibleException', reason: 'CoreData could not fulfill a fault
for '0x1dcf90 <x-coredata://DC02B10D-555A-4AB8-8BC4-F419C4982794/Blueprint/p"
