I am using a comboboxExt with a GridListControl as its popupcontrol. What I experienced is:
1)When the control is bound to a valid data set, I click on the drop down and get a list of items.
2)Without selecting any of item, change the programmatically condition so that the datasource of the control is set to null
3)Click on the dropdown arrow on the control again, an empty drop down list is displayed where nothing should have dropped down at all.
4)I tried calling ComboboxExt.Refresh() method everytime the datasource property is reset. Now the empty dropdown disappears. However, there is a empty white blank space showing in the place of the prior dropdown.
It is as if the comboboxext is remembering from the last dropdown and not refresh correctly with the new datasource.