Drop Down filter on Grid

Is it possible to add a drop down that can be used as a filter as part of the grid? I know this will not be a standard DHTMLX grid filter and that I will have to add the logic, but I would like to know if I can place the drop down on top of the grid column headers.
I am using this:

but it goes below the column headings.

and how can I increase the height of the top area so the filter and the drop down are visible?

You can place html container with custom drop down outside grid container and use makeFilter() method to create filter associated with dhtmlxGrid. Please find more information here docs.dhtmlx.com/doku.php?id=dhtm … iltering&s[]=filter