Question

I have been given a form to amend which is populated from a dataset when it is loaded.
There is an ID field in the dataset which is displayed in one of the fields on the form. In instances where this ID field is missing I need to display a lookup in this field where the user
can select from a couple of reasons why it is missing, and if the ID is present I need to display it and not show the lookup.

I have been struggling to find the syntax that would enable me to do this, and any advice would be appreciated.

Answer 1

I hope I understood the question properly

procedure TForm1.DataSourceDataChange(Sender: TObject; Field: TField);
begin
   if Field = MyFieldOfInterest then
     begin
        MyLookupComponent.visble := Field.IsNull;
        MyIDOnlyComponent.visble := not Field.IsNull; // or enabled ...
     end;
end;