BEx Callback to AfO Callback migration

[dsakq]

Hello,

I'm currently dealing with a very old BEx workbook that has some VBA code in it. There is a Sub 

Public CallBack(ParamArray varname())
  'Currently this callback routine is only called for Grid Items
  'varname(0): BExExcelItem.DataProvider.Name
  'varname(1): BExExcelItem.Range
  'varname(2): BExExcelItem.Name
......
End Sub

that has been registered in the BEx Menu to be called after variables refresh.

Now I need to get this working with AfO... I figured out to register the callback as described here https://help.sap.com/docs/SAP_BUSINESSOBJECTS_ANALYSIS_OFFICE/ca9c58444d64420d99d6c136a3207632/f26f5...

However I can't access varname() anymore. Is there some kind of equivalent to this?