dataview difference between developer visual and P...

Hi,

I am getting the matrix dataview in my custom visual and checking matrix.rows.root.children.length to see whether the user has one item selected at the top level so I can display a message otherwise. This works great in the developer visual.

On Desktop, when only 1 item is filtered at top level, I get 2 children instead of 1. The second one appears to be empty (value, id undefined). Any idea why I would get another child on Desktop? In case it matters, I am using fetchmoredata and this is the first call to update (create mode) when segment is true. Not sure if the same issue would occur without that.

Also, is there any support for fetchmoredata in the developer visual? It seems like you can only get the full dataview, correct?

Thanks!

John