PULLDN()

  Short:
  ------
  PULLDN() Pulldown menu creator, handler

  Returns:
  --------
  <nSelection> => Selection in the form menu.prompt
  (i.e. 2.04)

  Syntax:
  -------
  PULLDN(nSelection,aOptions,[aAttributes],[aColumns])

  Description:
  ------------
  Draws a pulldown menu with up to 8 separate boxes.
  Selection process starts with <nSelection>.

  Each element of <aOptions> defines a menu.

  A menu definition is a delimited string in the form:

        "TITLE:prompt:prompt:prompt"

  with up to 99 prompts per string.

  When a selection is made, the number of the selection
  is returned, in the form BOX.OPTION . So option 2 in box 3 would
  come back as 3.02.

  [aAttributes] is a box definition array. It is 7
  elements long and defines the following:

  Element:          1. <lDraw>      Draw top bar box? T/F
                    2. <cBarColor>  Top bar color
                    3. <cBoxColor>  Menu Box color
                    4. <cBoxFrame>  Menu Box frame
                    5. <nShadowPos> Menu Box shadow position
                               (0,1,3,7,9)
                    6. <nShadowAtt> Menu Box shadow attribute
                    7. <nBarRow>    Row to start menu bar

  [aColumns] is an array of title column positions to
  override the internal 'figerin algorithm.

  Examples:
  ---------
   aOptions := { "Datafiles:Use Datafile",;
                 "Indices:Select Indices:Index order",;
                 "Editing:Replacement:Tabular Edit",;
                 "Reporting:Build Query:Print Lists",;
                 "Other:List file:Change Directory",;
                 "Quit" }

   aAttrib := { .t.,;               // draw the top bar box
                'W/B,GR/R,,,W/N',;  // top bar color
                'W/B,N/R,,,W/N',;   // drop box color
                cSingle_frame,;     // drop box frame
                3,;                 // drop box shadow position
                8,;                 // drop box shadow  attribute
                0 }                 // row # of menu bar

   nSel  := 1.01
   do while .t.
       nSel := PULLDN(nSel,aOptions,aAttrib)
       do case
       CASE nSel = 0  && TRAP 0
           nSel = 1.01
       case nSel = 1
       case nSel = 2
       case nSel = 3
       case nSel = 4
       endcase
   enddo

  Warnings:
  ----------
  It takes some work to start all options and titles
  with a first letter that is unique so that first letter selection may
  take place.

  Notes:
  -------
  First letter selection takes place on the following
  priority: next matching element first letter, next matching box
  title first letter.

  Passing a menu array element with title only will
  result in no menu box, with the title being the only selection
  and returning a selection value of <MENU>.1.
  (i.e. a 'Quit' box)

  Source:
  -------
  S_PULLDN.PRG