Dynamic Filtering

Apologies I didn't read the examples.

Is the Item code a load filter or a Slicer on all the data?

 If a slicer then add a measure like this and Filter by the slicer for Item code and  in the filter pane HasGV>0

HasGV = 
VAR GV = "GV100"
RETURN
    CALCULATE (
        COUNT ( Trans[Transaction Id] ),
        FILTER (
            ALL ( Trans ),
            Trans[Transaction Id] = MAX ( Trans[Transaction Id] )
                && Trans[Item Code] = GV
        )
    )

Yeah the calc doesn't work for the order number but the whole table.

I tried a different tactic using a summary table. Here is another doc

https://1drv.ms/u/s!Aln7Q7AFJHneiW2FVW26L2xmf6OQ

Maybe this page will help use as it seems to solve a similar problem.

http://www.daxpatterns.com/basket-analysis/