Text Box Question!!!!

[Bruski]

Hello i need some serious help most of my gui is done but i need some help. I want to put a check box so that ppl get to choose weather or not they have a membership and another if they want one...my problem is that i dont know how to make it that when they click buy membership, the discount is shown and the amount of the membership is put in the membership fee when you press calc...

for example...

if they have membership...put automatic discount
if they dont have membership...they go to the next two boxes and are asked if they want to purchase one, if no then the calculation is processed without discount or mem fee but if yes then a mem fee is added to the total and a discount is also taken away...plz plz plz help this is due tuesday and its worth like 20% of my mark...thx again heres the code...

code:

import GUI View.Set ("graphics:400;300,nobuttonbar") var nameTextField, addressTextField, cityTextField, provinceTextField, costTextField : int var total, tax, cost, subTotal, GSTtot, PSTtot, discount, membership : real var tot := "" var sub := "" var gst := "" var pst := "" var dis := "" var mem := "" const gstTax:=0.07 const pstTax:=0.08 var draw : boolean := false tax := 0.15 colorback (black) procedure NameEntered (text : string)    GUI.SetSelection (addressTextField, 0, 0)    GUI.SetActive (addressTextField) end NameEntered procedure AddressEntered (text : string)    GUI.SetSelection (cityTextField, 0, 0)    GUI.SetActive (cityTextField) end AddressEntered procedure CityEntered (text : string)    GUI.SetSelection (provinceTextField, 0, 0)    GUI.SetActive (provinceTextField) end CityEntered procedure ProvinceEntered (text : string)    GUI.SetSelection (costTextField, 0, 0)    GUI.SetActive (costTextField) end ProvinceEntered procedure CostCD (text : string)        total := strreal (text) + strreal (text) * tax    tot := realstr (total, 10)    subTotal :=strreal (text)    sub := realstr (subTotal, 10)    GSTtot :=strreal (text) * gstTax    gst := realstr (GSTtot, 10)    PSTtot :=strreal (text) * pstTax    pst := realstr (PSTtot, 10)    discount:=strreal (text) + strreal (text) *1.15    dis:=realstr (discount, 10)    membership:=strreal (text) + strreal (text) *1.15    mem:=realstr (membership, 10) end CostCD procedure emptyf (text : string)    tot:= ""    sub:= ""    gst:= ""    pst:= ""    dis:= ""    mem:= "" end emptyf procedure caculate ()    draw := true end caculate GUI.SetBackgroundColor (yellow) %declare fields & labels nameTextField := GUI.CreateTextFieldFull (65, 250, 100, "", NameEntered, GUI.INDENT, 0, 0) var nameLabel := GUI.CreateLabelFull (55, 250, "Name:", 0, 0, GUI.RIGHT, 0) addressTextField := GUI.CreateTextFieldFull (65, 220, 100, "", AddressEntered, GUI.INDENT, 0, 0) var addressLabel := GUI.CreateLabelFull (55, 220, "Address:", 0, 0, GUI.RIGHT, 0) cityTextField := GUI.CreateTextFieldFull (65, 190, 100, "", CityEntered, GUI.INDENT, 0, 0) var cityLabel := GUI.CreateLabelFull (55, 190, "City:", 0, 0, GUI.RIGHT, 0) provinceTextField := GUI.CreateTextFieldFull (65, 160, 100, "", ProvinceEntered, GUI.INDENT, 0, 0) var provinceLabel := GUI.CreateLabelFull (55, 160, "Province:", 0, 0, GUI.RIGHT, 0) var taxtf := GUI.CreateTextFieldFull (235, 130, 155, "", emptyf, GUI.INDENT, 0, 0) var subTotalf := GUI.CreateTextFieldFull (235, 250, 155, "", emptyf, GUI.INDENT, 0, 0) var gstf := GUI.CreateTextFieldFull (235, 160, 55, "", emptyf, GUI.INDENT, 0, 0) var pstf := GUI.CreateTextFieldFull (335, 160, 55, "", emptyf, GUI.INDENT, 0, 0) var disf := GUI.CreateTextFieldFull (235, 190, 155, "", emptyf, GUI.INDENT, 0, 0) var memf := GUI.CreateTextFieldFull (235, 220, 155, "", emptyf, GUI.INDENT, 0, 0) costTextField := GUI.CreateTextFieldFull (65, 130, 100, "", CostCD, GUI.INDENT, 0, 0) var gtax := GUI.CreateLabelFull (225, 130, "Total:", 0, 0,GUI.RIGHT, 0) var ggst := GUI.CreateLabelFull (225, 160, "GST:", 0, 0,GUI.RIGHT, 0) var gpst := GUI.CreateLabelFull (325, 160, "PST:", 0, 0,GUI.RIGHT, 0) var gsub := GUI.CreateLabelFull (225, 250, "Subtotal:", 0, 0,GUI.RIGHT, 0) var gdis := GUI.CreateLabelFull (225, 190, "Discount:", 0, 0,GUI.RIGHT, 0) var gmem := GUI.CreateLabelFull (225, 220, "Mem Fee:", 0, 0,GUI.RIGHT, 0) var costLabel := GUI.CreateLabelFull (55, 130, "CD Cost:", 0, 0, GUI.RIGHT, 0) var quitBtn : int := GUI.CreateButton (100, 80, 0, "Quit", GUI.Quit) var calcb : int := GUI.CreateButton (160, 80, 0, "Calculate", caculate) var clearScrn : int := GUI.CreateButton (245, 80, 0, "Clear Screen", caculate) loop    if draw then        GUI.SetText (taxtf, tot)        GUI.SetText (subTotalf, sub)        GUI.SetText (gstf, gst)        GUI.SetText (pstf, pst)        GUI.SetText (disf, dis)        GUI.SetText (memf, mem)        draw := false    end if    exit when GUI.ProcessEvent end loop

thanks yet again alex