Core data issue with transient and binary data properties

FROM : Barry Wilson
DATE : Sun Jun 25 20:13:10 2006

Greetings,

I made a recent change to my application where I implemented 
accessors for a NSRect following the code as outlined in the core 
data programming guide.

I have two properties, one transient "myRect" and another 
"myRectAsDaa" coded exactly as the example code with the rect being 
converted into an NSValue and archived into NSData in the set accessor.

The first time I launched my application after making these changes 
(not yet storing anything into the property) I noticed a message upon 
freeing my document that essentially said "unable to set nil value 
for myRect". Now I didn't understand why core data wanted to set a 
transient value to nil but I knew how to fix that and added code fin 
setNilValueForKey to handle it. Now freeing the document gives me a 
failure and message that NSKeyedArchiver cannot encode a struct.

So what is going on here? Should core data be setting this property 
to nil in the first place? And is there a problem with archiving 
[NSValue valueWithRect:myRect] ?

-Barry