Here is a short piece of code that details the databinding code for adding a drop down list in a Janus grid
'bind the dropdown
Me.GridEX1.DropDowns("slprsnid").DataSource = db._4P_RM00301_SEL()
'bind the grids
Me.GridEX1.DataSource = db.FP_SOP10101_SEL_byOrder(m_strSopnumber, m_intSoptype)