Pass formdatasource to class

I have a form with two datasources, dsMaster and dsDetail.
dsDetail is joined with dsMaster with linktype = active.

The data from dsMaster is shown in a grid on tabpage Overview and the data from dsDetail is
shown on the grid in the tabpage Forecast.
On the executequery() method on the dsMaster I call a method from an class to set the filter ranges
and then call the super(). If I want to filter on the dsDetail, do I have to pass the dsDetail datasource to
class also? In other words, do I have to pass both formdatasources to the class to set the ranges on
both datasources?

Please help!

I am having a similar issue, did you ever figure this out?