Hi,

Using TCombobox to select an item from a list works fine. However I
can only get the ItemIndex.

I had the same problem in Delphi and there I added a property
"FocusedKey : Integer". The implementation looks like this:

function TBSCustomComboBox.GetFocusedKey: Integer;
begin
 if (ItemIndex <> -1)
   then Result := GetKeys(ItemIndex)
   else Result := 0;
end;

procedure TBSCustomComboBox.SetFocusedKey(AValue: Integer);
var
 ix : Integer;
begin
 for ix := 0 to Items.Count - 1 do
   if (GetKeys(ix) = AValue) then begin
     ItemIndex := ix;
     Exit;
   end;
 ItemIndex := -1;
 CheckMandatory;
end;

function TBSCustomComboBox.GetKeys(AIndex: Cardinal): Integer;
begin
 Result := Integer(Items.Objects[AIndex]);
end;


Basically I used the Objects property of the Items to save any key for
a certain item. Like this I could resort items (e.g. depending on
language) but the selected id (FocusKey) is always the same. It's also
usefull, if the Items sometimes have a subset only or if you add a new
item, that should apear on the top but you don't want to change all
id's.

I know the OPTION element in SELECT has a value property in HTML. But
I have no idea, how I could implement that in EWB right now.

cu Christian

Christian,

What is the problem you are actually trying to solve here? It looks like you are
wanting to link a combo box text to a particular value yes? I just use a separate
list in the form, and keep them in sync.

/Matthew Jones/

>What is the problem you are actually trying to solve here? It looks like you are
>wanting to link a combo box text to a particular value yes? I just use a separate
>list in the form, and keep them in sync.

Sure I could do that, but I use this in different places again and
again. Here an example:

I start with a type in Delphi:

TBSSwClubType = (sctClub, sctRegion, sctNation)

First, everything is fine. I can map directly to the ItemIndex. Now I
add a new type:

TBSSwClubType = (sctClub, sctRegion, sctNation, sctInterRegion);

I do this at the end, because I mapped the values to a database
integer field as well. But for the Combobox I want a different order:

sctClub
sctRegion
sctInterregion
sctNation

Therefor I created this FocusedKey property to use the TCombobox with
a list of items, where the Key <> ItemIndex.

I did that ten years ago. Couldn't live without it in Delphi.

cu Christian

I don't know if the combo does the Data or Item property, but one way would be to
create a class that you use to link things up. So you'd create a form member of
MyLink : TComboLink and use
MyLink := TComboLink.Create(comboClubType) to associate things. Not ideal, but
saves repeating things. And it works back in Delphi land too.

Just a suggestion!

/Matthew Jones/

>I don't know if the combo does the Data or Item property, but one way would be to
>create a class that you use to link things up. So you'd create a form member of

That's what I plan to do. I already have my own base class for forms
and I plan to play around with doing that for TCombobox. Not 100%
sure, if the IDE will be able to deal with it, but since it will be
only runtime properties, it may work.

cu Christian