Lisp to Create Layer Filters - Add Two Features?

[mjs9199]

I have the below lisp put together (I found it somewhere, probably somewhere here on the discussion group).  I have two features I'd like to add:

1. How do I create a layer filter (via lisp) that shows only frozen layers, or only thawed.  I know it has to do with the flags attribute of the list definition, but I don't know what values to plugin.

2. How can I create a layer filter that is a sub of another filter?  You can do it with the dialog box, so I hope there is a way to do it with lisp.

Example would be a parent filter of "Utilities" and a child filter of "Utilities . Storm"

Here is the code I have so far:

	(defun c:laf (/ filtlst lfiltobj safecode safefilt)
	
		(vl-load-com)

		(setq filtlst (list
				;;name lay col lt flags lw plot
				(list "Active Drawing" "~*|*" "*" "*" 0 "*" "*")
				(list "Civil 3D" "X?-*,Z?-*" "*" "*" 0 "*" "*")
				(list "Divides I" "H1-*,Hp-*,*|H1-*,*|Hp-*" "*" "*" 0 "*" "*")
				(list "Divides II" "H2-*,Hp-*,*|H2-*,*|Hp-*" "*" "*" 0 "*" "*")				
				(list "E+S I" "O1-*,Op-*,*|O1-*,*|Op-*" "*" "*" 0 "*" "*")
				(list "E+S II" "O2-*,Op-*,*|O2-*,*|Op-*" "*" "*" 0 "*" "*")
				(list "Base" "B?-*,*|B?-*" "*" "*" 0 "*" "*")
				(list "Grading" "G?-*,*|G?-*" "*" "*" 0 "*" "*")
				(list "Site" "S?-*,*|S?-*" "*" "*" 0 "*" "*")
				(list "Utilities" "U?-*,*|U?-*" "*" "*" 0 "*" "*")
				(list "Landscape" "L?-*,*|L?-*" "*" "*" 0 "*" "*")
				(list "Lighting" "I?-*,*|I?-*" "*" "*" 0 "*" "*")
				(list "Profiles" "P*,*|P*" "*" "*" 0 "*" "*")	
					;is this correct or should it be P-*,Pe-*,Pp-* ??
				(list "State . Prop" "?p-*,*|?p-*" "*" "*" 0 "*" "*")
				(list "State . Ex" "?e-*,*|?e-*" "*" "*" 0 "*" "*")
				(list "State . Demo" "?d-*,*|?d-*" "*" "*" 0 "*" "*")
				(list "Util . San" "*-san*" "*" "*" 0 "*" "*")
				(list "Util . Storm" "*-stm*" "*" "*" 0 "*" "*")
				(list "Util . Water" "*-watr*" "*" "*" 0 "*" "*")
				
				(list "_Frozen" "*" "*" "*" 0 "*" "*")

				;need filters for:
				;	1st letter
				;	...layer properties (all on, all off, all thaw, all frozen
				;			be sure to sort together in list of layer filters
					)
				lfiltobj (vla-addobject
							(vla-getextensiondictionary
								(vla-get-layers
									(vla-get-activedocument
										(vlax-get-acad-object)
									)
								)
							)
							"acad_layerfilters"
							"acdbdictionary")
				safecode (vlax-make-safearray 2 '(0 . 6))
				safefilt (vlax-make-safearray 12 '(0 . 6)))

		(vlax-safearray-fill safecode (list 1 1 1 1 70 1 1))

		(foreach
			sublst filtlst
				(vlax-safearray-fill
					safefilt
					(mapcar '(lambda (x) (vlax-make-variant x 8)) sublst))
				(vla-addxrecord lfiltobj (nth 0 sublst))
				(vla-setxrecorddata
				(vla-item lfiltobj (nth 0 sublst))
				safecode
				safefilt
				)
		)
		(prin1)
		(princ "\n...All layer filters have been created.")
		(princ)
	)