Quite a lot going on recently, but normal service should be resumed again soon

This would cause the viewPosition sequence to skip a number – 0,1,2,4,5. This problem in turn actually stops you from dragging an item to the end of the table. In my case with 5 items, dragging the item to the end of the list in the table would only ever put it 2nd last.

The way I got around this was to make a simple change in tableView:acceptDrop

change

tempRow = row;
to
tempRow = row – 1;

Hope this helps anybody else experiencing this little problem.

But many thanks again for this post – can’t tell you how much work it saved

I had just ventured beyond using single nib, single window controller core data apps to something a bit more complex and was stumped. Your tutorial smashed it!

Thanks for the work!

It should read -(void)set_YourClassName_Dictionary. Re-add the setter that you removed in Tim’s original tutorial.

1. I subclassed NSTextFieldCell, rather than NSCell. (I’m not sure yet how to do this with just NSCell. In my case I have a name, and some read only metadata about the object I am displaying, so this works fine for me.)

2. Add the following to your NSManagedObject subclass (PersonObject in your example):

-(void)setDictionary
{
[self setValuesForKeysWithDictionary:aDictionary];
}

3. Subclass NSFormatter with the following methods (these are the minimum required to subclass NSFormatter, according to the documentation)

- (BOOL)getObjectValue:(id *)anObject forString:(NSString *)string errorDescription:(NSString **)error
{
if (anObject){
*anObject = [NSDictionary dictionaryWithObject:string forKey:@"name"];
return YES;
}
return NO; // This probably shouldn’t happen…Could be a bindings issue if it does?
}
- (NSString *)stringForObjectValue:(id)anObject
{
if (![anObject isKindOfClass:[NSDictionary class]])
return nil;
return [anObject valueForKey:@"name"]; // This will propagate back to your NSManagedObject subclass, since we created setDictionary.
}
- (NSAttributedString*)attributedStringForObjectValue:(id)anObject withDefaultAttributes:(NSDictionary *)attrs
{
if (![anObject isKindOfClass:[NSDictionary class]])
return nil;
NSAttributedString * anAttributedString = [[NSAttributedString alloc]initWithString: [anObject valueForKey:@"name"]];

return anAttributedString;
}

4. Add the following to your NSTextFieldCell’s awakeFromNib:
MyFormatter * aMyFormatter = [[[MyFormatter alloc]init]autorelease];
[self setFormatter:aMyFormatter];

That should be it, if I didn’t leave out any steps… I hope this helps someone, and if you spot anything that can be improved in my code, please post a followup!
-Tim

There are various resources on the web that offer other solutions, such as:
http://www.fatcatsoftware.com/blog/2008/per-object-ordered-relationships-using-core-data

Thanks,
Tim