Core Data: entity properties getting mixed

Question

I have an NSWindow which I use to create new records. After pressing the Add button, a certain method is called in which I do the following:

- (IBAction)addActionAddSheet:sender {
 NSManagedObjectContext *moc = [self managedObjectContext];
 NSManagedObject *newObject  = [NSEntityDescription insertNewObjectForEntityForName:@"Recipe" inManagedObjectContext:moc];

 [newObject setValue:[newRecipeName stringValue] forKey:@"name"];
 [newObject setValue:[newRecipeInstructions string] forKey:@"instructions"];

 NSLog(@"New object is: %@", newObject);

 [NSApp endSheet:addSheet];
 [addSheet orderOut:sender];
}

The (edited) output from NSLog after I have executed this twice, is as follows:

<NSManagedObject: 0x10045c6a0> (entity: Recipe; id: 0x1004564a0 <x-coredata:///Recipe/t18FEC674-8937-49DF-A18B-940EF82E83C32> ; data: {
    instructions = X;
    name = X;
})
<NSManagedObject: 0x1149069a0> (entity: Recipe; id: 0x100106a20 <x-coredata:///Recipe/t18FEC674-8937-49DF-A18B-940EF82E83C33> ; data: {
    instructions = Y;
    name = Y;
})

This is completely as expected. However, my tableview, which is bound to an array controller, shows that both objects X and Y have X as value for instructions.

When I exit my application and the data is saved, what I see in my xml file is again different:

    <attribute name="name" type="string">Y</attribute>
    <attribute name="instructions" type="string">Y</attribute>

    <attribute name="name" type="string">X</attribute>
    <attribute name="instructions" type="string">Y</attribute>

This time they both have value Y.

The output from NSLog does show that I'm dealing with two different objects here, so I'm not sure what I might be doing that could influence both.

These are is my unedited output:

2009-12-07 14:46:18.409 Recipe[11578:a0f] managedObjectContext
2009-12-07 14:46:18.411 Recipe[11578:a0f] persistentStoreCoordinator
2009-12-07 14:46:18.411 Recipe[11578:a0f] managedObjectModel
2009-12-07 14:46:18.423 Recipe[11578:a0f] applicationSupportDirectory
2009-12-07 14:46:18.436 Recipe[11578:a0f] externalRecordsDirectory
2009-12-07 14:46:20.484 Recipe[11578:a0f] Show Add sheet
2009-12-07 14:46:20.485 Recipe[11578:a0f] Clear values
2009-12-07 14:46:20.494 Recipe[11578:a0f] call beginSheet
2009-12-07 14:46:23.632 Recipe[11578:a0f] addActionAddSheet: -- Add button clicked
2009-12-07 14:46:23.632 Recipe[11578:a0f] Create new mananged obj in context
2009-12-07 14:46:23.634 Recipe[11578:a0f] managedObjectContext
2009-12-07 14:46:23.635 Recipe[11578:a0f] Set values for name and instructions
2009-12-07 14:46:23.636 Recipe[11578:a0f] New object is: <NSManagedObject: 0x1001c89c0> (entity: Recipe; id: 0x1001c9470 <x-coredata:///Recipe/tE9BD4EE3-082C-4715-AB66-2C3580223F9E2> ; data: {
    instructions = A;
    name = A;
})
2009-12-07 14:46:23.636 Recipe[11578:a0f] call [NSApp endSheet:] and [addSheet orderOut:]
2009-12-07 14:46:23.637 Recipe[11578:a0f] addSheetDidEnd:returnCode:contextInfo: -- empty method
2009-12-07 14:46:35.327 Recipe[11578:a0f] Show Add sheet
2009-12-07 14:46:35.328 Recipe[11578:a0f] Clear values
2009-12-07 14:46:35.337 Recipe[11578:a0f] call beginSheet
2009-12-07 14:46:39.836 Recipe[11578:a0f] addActionAddSheet: -- Add button clicked
2009-12-07 14:46:39.836 Recipe[11578:a0f] Create new mananged obj in context
2009-12-07 14:46:39.838 Recipe[11578:a0f] managedObjectContext
2009-12-07 14:46:39.839 Recipe[11578:a0f] Set values for name and instructions
2009-12-07 14:46:39.843 Recipe[11578:a0f] New object is: <NSManagedObject: 0x102070ad0> (entity: Recipe; id: 0x10205e420 <x-coredata:///Recipe/tE9BD4EE3-082C-4715-AB66-2C3580223F9E3> ; data: {
    instructions = B;
    name = B;
})
2009-12-07 14:46:39.843 Recipe[11578:a0f] call [NSApp endSheet:] and [addSheet orderOut:]
2009-12-07 14:46:39.844 Recipe[11578:a0f] addSheetDidEnd:returnCode:contextInfo: -- empty method

Recipe A:

Recipe B:

My array controller:

My table column's bindings:

My label's binding:

Answer 1

How are you binding your table / columns to the array controller? It sounds as though your Instructions column isn't bound to arrangedObjects.instructions, but possibly selection.instructions.