Description
If enabled, this event is reported when the user clicks the drop-down button in a Combo, ComboEx, ColorButton, DateTimePicker or Menu object, just before the drop-down list, colour selection, calendar or -menu is displayed.
For a Button this event only applies if the Style of the Button is Split. For such a Button and for the ButtonEdit object there is no default processing for the event and it is the responsibility of the programmer to take appropriate action in a call-back function.
For a DateTimePicker this event only applies if the Style of the DateTimePicker is 'Combo'.
The event message reported as the result of ⎕DQ, or supplied as the right argument to your callback function, is a 2-element vector as follows :
| [1] | Object | ref or character vector |
| [2] | Event | 'DropDown' or 45 |
This event is reported for information only and cannot be disabled or modified in any way.
The associated callback is run immediately while the windows notification is still on the stack. See High-Priority Callback Functions.