Can't show horizontalscrollbar in a list box in PDA built(in windows ok)

[donnie]

Hi there,
I have made a procedure that adds a horizontal scroll bar in a list box(according to the maximum string in the list).But when I build it for my PDA it doesn't show anything.In windows everything is ok...
Here is the code...

Code: [Select]

procedure Tform1.SetHorizontalScrollBar(lb : TListBox) ;
var
  j, MaxWidth: integer;
begin
  MaxWidth := 0;
  for j := 0 to lb.Items.Count - 1 do
  if MaxWidth < lb.Canvas.TextWidth(lb.Items[j]) then
    MaxWidth := lb.Canvas.TextWidth(lb.Items[j]) ;

  SendMessage(lb.Handle,
              LB_SETHORIZONTALEXTENT,
              MaxWidth + GetSystemMetrics(SM_CXFRAME), 0) ;
end;
What does it need to show it at PDAs as well?