You can let FoxPro handle it by disabling unavailable items with "\" prefix. See sample code below

PUBLIC ofrmListExamples
ofrmListExamples=NEWOBJECT("frmListExamples")
ofrmListExamples.Show
RETURN

DEFINE CLASS frmListExamples AS form

 DataSession = 2
 Top = 0
 Left = 0
 Height = 262
 Width = 325
 Caption = "List and ListItem Array Example"
 Name = "frmListExamples"

 ADD OBJECT cbolistitem AS combobox WITH ;
  ColumnCount = 1, ;
  ColumnWidths = "100,100,50", ;
  Left = 34, ;
  Sorted = .T., ;
  Style = 2, ;
  TabIndex = 3, ;
  Top = 154, ;
  Name = "cboListItem"


 PROCEDURE cbolistitem.Init
  WITH This
   .AddItem( 'Apple' )
   .AddItem( 'Banana' )
   .AddItem( '\Carrot' )
   .AddItem( 'Orange' )
  ENDWITH
 ENDPROC
ENDDEFINE
 

>Note: Please excuse, I wrote Listbox in the subject, I meant Combobox.
>
>Does anyone know if there is a way to make certain items within a combobox to display with a different forecolor then the rest of the items? I am trying to create a combobox that has a list of items, but based on other selections elsewhere on the form, certain items in the list of the combobox turn gray. Those gray items I would like to be able to "test" for so that I can disallow the selection of those items by the user interactively.
>
>If there is no way to do that with the existing combobox within FoxPro, does anyone know of an any other control I can maybe download and use that can accomplish this? Or maybe how to create such a control from scratch? Any help would be greatly appreciated.