Reading ItemIndex from a cell

How do I read selected ItemIndex from a cell which has edComboList editor?

I prefill the AdvStringGrid->Combobox with some items, and then use OnGetEditorType event to set which cells use the Combobox. All good.

What I cannot find how to read the actual selected item from the grid... e.g. AdvStringGrid->Cells[0,0]->ItemIndex something like that.

Grid.ComboIndex[col,row]: integer;