Subject Re: [IBO] TIB_LookupCombo to allow selecting
Author Geoff Worboys
> OK, pressing DEL seems to work... but it isn't the obvious
> way of selecting <none> for me. It would be more self-
> explaining for the end user if there was an 'empty' line
> in the combobox-list that he could select.
> Any ideas how to accomplish this?

This was actually discussed a little while ago. Here is a snippet of
one of my previous comments...

- - - -
I think the major problem is that it would not be practical
to implement. Inserting a dummy entry into the selection list
for a lookup would be a lot of work - especially allowing for
individual tastes that may want such an option forced to the
top, the bottom or perhaps within the sort order. At the
moment the lookup control works using a standard IB_Grid to
display the list. For it to support a non database entry would
mean building a specialised display grid just for this control.
Also, given that the lookup may be over a dataset of many
thousands of records and that IBO can setup refined incremental
searching so that it may not even see the top or bottom of the
dataset, it is difficult to see how the idea could be
implemented efficiently.
- - - -

So if you really want a "<none>" selection you need to actually add
that as a record in your lookup table. Then set your foreign key
declaration to not null so that the user is forced to choose
something, even if it is the "<none>" selection.


Geoff Worboys
Telesis Computing