VMENU()         "Pull-Down" menu system

Description:
  VMENU() provides the programmer with a very fast and efficient means
  of producing "pull-down" menus for their users.  VMENU() is screen
  destructive.


Syntax:     
  VMENU( <expAC1>, <expAN1>, <expAN2>, <expAC2>, <expAC3>, <expN>,
  <expAL> )


Pass:       
  <expAC1> = List of all available options on all available menus

  <expAN1> = List of where each menu begins

  <expAN2> = List of where each menu ends

  <expAC2> = List of messages for each menu option

  <expAC3> = Title array

  <expN>   = Number of elements in <expAC3>

  <expAL>  = Parallel array of logical values.  If a value in this array
  is .F., the parallel element in <expAC1> is disabled


Return:     
  <expN>   = Option (element) the user selected


Notes:      


Example:    
  PRIVATE ac_Options[50]
  PRIVATE an_Start[10]
  PRIVATE an_End[10]
  PRIVATE ac_Msgs[10]
  PRIVATE ac_Title[4]
  PRIVATE n_Elements
  PRIVATE al_Avail[50]

  * Set up the title
  n_Elements  = 4
  ac_Title[1] = ""
  ac_Title[2] = "Sample menu system"
  ac_Title[3] = DTOC(DATE())
  ac_Title[4] = ""

  * Menu across top
  an_Start[1]    = 1
  an_End[1]      = 4
  ac_Options[1]  = "Maintenance"
  ac_Options[2]  = "Reports"
  ac_Options[3]  = "Utilities"
  ac_Options[4]  = "Other"

  * First pull-down
  an_Start[2]    = 10
  an_End[2]      = 12
  ac_Options[10] = "Clients     "
  ac_Options[11] = "Products    "
  ac_Options[12] = "SalesPersons"

  * Second pull-down
  an_Start[3]    = 15
  an_End[3]      = 18
  ac_Options[15] = "Client list     "
  ac_Options[16] = "Product list    "
  ac_Options[17] = "Territory Report"
  ac_Options[18] = "Performance Log "

  * Third pull-down
  an_Start[4]    = 20
  an_End[4]      = 21
  ac_Options[20] = "Pack databases"
  ac_Options[21] = "Re-Index      "

  * Fourth pull-down
  an_Start[5]    = 25
  an_End[5]      = 27
  ac_Options[25] = "Set colors         "
  ac_Options[26] = "Product information"
  ac_Options[27] = "Quit               "

  * Enable each option
  FOR n_Cntr = 1 TO 50
     al_Avail[n_Cntr] = .T.
  NEXT n_Cntr

  * Set all the messages to nothing
  FOR n_Cntr = 1 TO 10
     ac_Msgs[n_Cntr] = ""
  NEXT n_Cntr

  DO WHILE .T.

     n_Choice = VMENU(ac_Options, an_Start, an_End, ac_Msgs, ac_Title,
  n_Elements, al_Avail)

     DO CASE

        CASE n_Choice = 1
           DO CLNT_MNT

        CASE n_Choice = 2
           DO PROD_MNT
        .
        .
        .

        CASE n_Choice = 27
           IF ASK("Are you sure","YyNn") $ "Yy"
              EXIT
           ENDIF

     ENDCASE

  ENDDO

  QUIT


Usage: