FoxPro/Visual FoxPro - listbox - filtrar el contenido al hacer click o dobleclick en el mismo

* Init del Formulario

PROCEDURE Init

	LOCAL lnTally, i

		&& Agrego dos propiedades al formulario (Para controlar los ListBox)

		ADDPROPERTY(thisform,"rubro","")

		ADDPROPERTY(thisform,"codprod","")

		SELECT distinct pro.tipo,rub.describe ;

			FROM produc as pro,ustipo as rub ;

			WHERE pro.tipo = rub.tipo ;

			INTO ARRAY laRubros

		lnTally = _tally

		WITH this.lst_list1

			.clear

			.boundcolumn=2

			.Columncount = 2

			.Columnlines = .f.

			.columnwidths = "200,40"

			.ControlSource = 'thisform.rubro'

			FOR i = 1 TO m.lnTally

				.AddListitem(PROPER(laRubros[i,2]),i,1)

				.addListitem(laRubros[i,1],i,2)

			NEXT

			.requery

			.refresh

		ENDWITH

	ENDPROC

* Codigo que debe colocarse en el Click y DblClick del control "lst_list1"

	PROCEDURE Lst_list1.Click

		thisform.get_products(this.ListItem(this.ListItemId,2))

	ENDPROC

	PROCEDURE Lst_list1.DblClick

		thisform.get_products(this.ListItem(this.ListItemId,2))

	ENDPROC

* Codigo del método Get_Produc

	PROCEDURE get_products

		LPARAMETERS tcRubro

		LOCAL ARRAY laPRoduc(1)

		LOCAL i,lnTally

		SELECT descrip,marca,codprod FROM produc WHERE tipo==tcRubro INTO ARRAY laproduc

		lnTally = _tally

		this.codprod = IIF(m.lnTally > 0 ,laProduc[1,3],"")

		WITH this.lst_list2

			.clear

			.boundColumn = 3

			.ColumnCount = 2

			.columnLines = .f.

			.ColumnWidths = "200,100"

			.ControlSource = 'thisform.codprod'

			FOR i= 1 TO m.lnTally

				.addListitem(PROPER(laProduc[i,1]),i,1)

				.addListitem(laProduc[i,2],i,2)

				.addlistitem(laProduc[i,3],i,3)

			ENDFOR

			.requery

			.refresh

		ENDWITH