about template field gridview

Question

Hi all!
for my website for filling the vendor info i take a template field gridview.It contains 4 fields like item code,item name, vendor item code, vendor item cost.
I want that the first field item code(a dropdown list) show all the itemid s from table base_product. so for binding it i right click the drop-down list go to edit template, choose the column name & do all things required to bind a data source to a drop-down list.but at end it is showing "databound"but the data is not shown.
another field item name( a textbox) should also fill like that.The remaining fields should be manually filled by the user.so wht should i do now?Does the template field gridview works in this context? or there is anothe code?
Help me guys!!!