not key value coding-compliant

FROM : David Alter
DATE : Wed Jul 12 01:20:12 2006

I want to store NSImages in core data. To do this I did the following

1) In my data model I set the attribute type to be "Binary Data"
2) In the sub class of my NSManagedObject  I added some methods


- (void)setArtwork:(NSImage *)value
{
   [self willChangeValueForKey: @"artwork"];
   [self setPrimitiveValue: value forKey: @"artwork"];
         [self didChangeValueForKey: @"artwork"];
}

- (NSImage *)artwork
{
   NSData * tmpValue;
   [self willAccessValueForKey: @"artwork"];
         tmpValue = [self primitiveValueForKey: @"artwork"];
         [self didAccessValueForKey: @"artwork"];
   return tmpValue;
}

- (void)willSave
{

      NSImage *tmpImage = [self primitiveValueForKey:@"artwork"];
    if (tmpImage != nil) {
        [self setPrimitiveValue:[NSArchiver 
archivedDataWithRootObject:tmpImage] forKey:@"artworkData"];
    } else {
        [self setPrimitiveValue:nil forKey:@"artworkData"];
    }

    [super willSave];
}

- (void)awakeFromFetch
{

    NSData *imageData = [self valueForKey:@"artworkData"];
    if (imageData != nil) {
        NSImage *image = [NSUnarchiver 
unarchiveObjectWithData:imageData];
        [self setPrimitiveValue:image forKey:@"artwork"];
   }
}


3) I did a quick interface in IB and used Binding to link things up .

4) The data gets loaded from and external data source the first time 
the application runs.

When i run it and try to save the persistent store I get "This class 
is not key value coding-compliant for the key artworkData" Do I need 
to have a "setArtworkData:(NSData*)" and "(NSData*)artworkData" 
method in my subclass of NSManagedObject? Or is there another peace 
of this I'm missing.

thanks for the help

-dave