ColumnComboBox alignment issue


Windows 10 x64
TMS Component Pack
Delphi Berlin 10.1 update 1

Let's say you have a ColumnComboBox with a  width of 200 positionned to the right side of the form and items with a width of around 500 (in the dropdown).

We work with 2 monitors.

The form is near right edge of the left monitor. When you dropdown the combo, you will see part of the dropdown on the left monitor and part of it on the right monitor.

I could not find a property that would allow me to control the position of the dropdown.
Is this something that can be improved?
Something like tje DropDownAlign property of the TDBLookupComboBox would do the trick.


TColumnComboBox descends from a regular VCL TComboBox (wrapper around the Windows COMBOBOX class) and inherits therefore its behavior of the dropdown position from a standard VCL TComboBox. The behavior on a multimonitor config is as such the same and unfortunately, we haven't found a way to override/change this behavior. TDBLookupComboBox is a custom control not descending from TComboBox and implements its dropdown behavior fully itself. As an alternative to TColumnComboBox, you could consider our TAdvMultiColumnDropDown that is also a full custom implementation that takes multi monitor configs in account.