NSDistantObject enumeration - cocoa

Question

I was make communication for client-server application and have strange problem.
here is a code where i pickup objects.
- (byref NSArray*)objectsOfName:(bycopy NSString*)name
withPredicate:(bycopy NSPredicate*)predicate;
{
NSManagedObjectContext *context = [self managedObjectContext];
NSError *error = nil;
NSFetchRequest *request = [[NSFetchRequest alloc] init];
[request setEntity:[NSEntityDescription entityForName:name
inManagedObjectContext:context]];
[request setPredicate:predicate];
NSArray *results = [context executeFetchRequest:request error:&error];
[request release], request = nil;
if (error) {
NSLog(#"%#:%# Error on fetch %#", [self class], NSStringFromSelector(_cmd), error);
return nil;
}
//NSLog(#"%#:%# Result of fetch is %#", [self class], NSStringFromSelector(_cmd), results);
return results;
}
Here is pickup:
NSArray *destinations;
#ifdef SNOW_CLIENT
destinations = [server objectsOfName:#"DestinationsListWeBuy" withPredicate:predicate];
If i do
NSLog(#"Destination:%#\n",destinations);
i seen all objects in log.
If i try to do
NSLog(#"all:%#\n%#\n%#\n",[[destinations objectAtIndex:0] valueForKey:#"rate"],[[destinations objectAtIndex:0] valueForKey:#"lastUsedACD"],[[destinations objectAtIndex:0] valueForKey:#"lastUsedCallAttempts"]);
i seen attributes also.
But, if i try to do loop around objects:
for (NSManagedObject *dest in destinations)
{
NSLog(#"all:%#\n%#\n%#\n",[dest valueForKey:#"rate"],[dest valueForKey:#"lastUsedACD"],[dest valueForKey:#"lastUsedCallAttempts"]);
i have EXC_BAD_ACCESS in this part of code:
for (NSManagedObject *dest in destinations)
all debug technic, which i know, don't give me possibility to understand, what happened. (NSZombieEnabled = YES)
if i do loop at another manner:
for (NSUInteger count = 0;count < [destinations count]; count++)
NSLog(#"all:%#\n%#\n%#\n",[[destinations objectAtIndex:count] valueForKey:#"rate"],[[destinations objectAtIndex:count] valueForKey:#"lastUsedACD"],[[destinations objectAtIndex:count] valueForKey:#"lastUsedCallAttempts"]);
i seen all keys without exception. All nsmanagedobject's is subclassed.
If i need implement encodeWithCored method for all subclasses, examples is appreciated.
*UPDATE for Marcus *
This is how i receive objects from server side:
- (byref NSArray*)allObjects
{
NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
if (!coordinator) {
NSMutableDictionary *dict = [NSMutableDictionary dictionary];
[dict setValue:#"Failed to initialize the store" forKey:NSLocalizedDescriptionKey];
[dict setValue:#"There was an error building up the data file." forKey:NSLocalizedFailureReasonErrorKey];
NSError *error = [NSError errorWithDomain:#"YOUR_ERROR_DOMAIN" code:9999 userInfo:dict];
[[NSApplication sharedApplication] presentError:error];
return nil;
}
NSManagedObjectContext *moc = [[NSManagedObjectContext alloc] init];
[moc setPersistentStoreCoordinator:coordinator];
[moc setUndoManager:nil];
NSNotificationCenter *nc = [NSNotificationCenter defaultCenter];
[nc addObserver:self
selector:#selector(mergeChangesForClient:)
name:NSManagedObjectContextDidSaveNotification
object:thirdMOC];
NSFetchRequest *request = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:#"Carrier"
inManagedObjectContext:moc];
[request setEntity:entity];
[request setIncludesSubentities:YES];
NSError *error = nil;
NSArray *objects = [moc executeFetchRequest:request error:&error];
[request release], request = nil;
for (NSManagedObject *carrier in objects) {
NSSet *destinations = [carrier valueForKeyPath:#"destinationsListForSale"];
for (NSManagedObject *destination in destinations) [destination addObserver:self forKeyPath:#"rate" options:NSKeyValueObservingOptionNew context:nil];
}
if (error) {
NSLog(#"%#:%# error: %#", [self class], NSStringFromSelector(_cmd), error);
return nil;
}
return objects;
}
This is what i do with them on client side:
NSArray *allObjects = [server allObjects];
[carrierArrayController setContent:allObjects];
There is no serialization in this case. Any other ways (like send copy of server moc to client side doesn't work, it just generate exceptions on main.c).
p.s. many thanks to Marcus for his Core Data book.

Answer 1

unrecognized selector sent to class 0x1000a2ed8 2011-03-17 02:15:18.566 snowClient[19380:903] +[AppDelegate encodeWithCoder:]: unrecognized selector sent to class 0x1000a2ed8
That is not a core data problem. That is an error in your code where you are trying to call a method on an object that does not respond to that method. You need to track that down as it appears that you are trying to serialize your AppDelegate.
Update
What kind of class is 0x1000a2ed8? Break on the exception and print out the object to see what it is. Again, this is not a core data error directly, it is sending a messages to an object that does not respond to that message. It is possible that Core Data no longer allows you to send Managed objects across as distributed objects. It is possible that this is simply an issue with an over-released object. No way to know without further investigation.
Step one: Find out what object 0x1000a2ed8 is and see if the object changes from one run to the next.