I have an application that downloads an xml file, parses the file, and creates core data objects while doing so. In the parse code I have a function called 'emptydatacontext' that removes all items from Core Data before creating replacements items from the xml data. This method looks like this:

-(void) emptyDataContext
{
NSFetchRequest * allCon = [[NSFetchRequest alloc] init];
[allCon setEntity:[NSEntityDescription entityForName:@"Condition" inManagedObjectContext:managedObjectContext]];
NSError * error = nil;
NSArray * conditions = [managedObjectContext executeFetchRequest:allCon error:&error];
DebugLog(@"ERROR: %@",error);
DebugLog(@"RETRIEVED: %@", conditions);
[allCon release];

for (NSManagedObject * condition in conditions) {
    [managedObjectContext deleteObject:condition];
}

// Update the data model effectivly removing the objects we removed above.
//NSError *error;
if (![managedObjectContext save:&error]) {
    DebugLog(@"%@", [error domain]);
}

}

The first time this runs it deletes all objects and functions as it should - creating new objects from the xml file. I created a 'update' button that starts the exact same process of retrieving the file the proceeding with the parse & build. All is well until its time to delete the core data objects. This 'deleteObject' call creates a "EXC_BAD_ACCESS" error each time. This only happens on the second time through.

Captured errors return null. If I log the 'conditions' array I get a list of NSManagedObjects on the first run. On the second this log request causes a crash exactly as the deleteObject call does.

I have a feeling it is something very simple I'm missing or not doing correctly to cause this behavior. The data works great on my tableviews - its only when trying to update I get the crashes.

I have spent days & days on this trying numerous alternative methods. Whats left of my hair is falling out. I'd be willing to ante up some cash for anyone willing to look at my code and see what I'm doing wrong. Just need to get past this hurdle.

Thanks in advance for the help!