Now I understand where "bloatware" comes from. :)
This will make your eye's water:

###################################
PROG_NAME = "Headache"

from Tkinter import *
PROG_SEARCHMODS = "><=#*~_"
PROGFw = {}
PROGFw["Qty"] = 7
PROGBar = {}

Root = Tk()
ROOTNameVar = StringVar()
ROOTQtyVar = StringVar()
ROOTQtyVar.set("HI")

Clr = {"R":"#FF0000", "D":Button().cget("bg")}



####################
class vEntry(Entry):
def __init__(self, master=None, bar = "", **kw):
Entry.__init__(self, master, **kw)
VCmd = (self.register(self.VCmd), '%s', '%P')
self.configure(vcmd = VCmd, validate='key')
self.MaxLen = self.cget("width")-1
self.icursor(END)
self.VarSet = bar
def VCmd(self, Old, New):
Max = self.MaxLen
if len(New) > 0:
# If the first character of the field's text is one of the search modifiers
# then allow one more character to be entered.
if New[0] in PROG_SEARCHMODS:
Max += 1
if len(New) > Max:
Root.bell()
return False
if self.VarSet != "":
PROGBar[self.VarSet].configure(bg = Clr["R"])
eval("%sBarSVar"%self.VarSet).set(1)
return True



###########################################
def chgPROGChgBar(VarSet, State, e = None):
if State == 1:
# This may be called upon to clear the change bar of a form that doesn't have
# a change bar, so try.
try:
PROGBar[VarSet].configure(bg = Clr["R"])
eval("%sBarSVar"%VarSet).set(1)
except:
pass
elif State == 0:
try:
PROGBar[VarSet].configure(bg = Clr["D"])
eval("%sBarSVar"%VarSet).set(0)
except:
pass
# For some routines to use so they don't have to constantly check to see if
# the change bar state should be changed. The call gets made, but nothing
# happens.
elif State == -1:
return
return



##################################################
def labelEntry(Sub, LabTx, TheVar, Max, Bar = ""):
Label(Sub, text = LabTx).pack(side = LEFT)
if isinstance(Max, basestring) or isinstance(Max, str):
Max = PROGFw[Max]
LEnt = vEntry(Sub, textvariable = TheVar, width = Max+1, bar = Bar)
LEnt.pack(side = LEFT)
return LEnt



######################
def rootDoSomething():
print "Working..."
# Clean all input fields (mostly .strip()'ing)
# Verify what was entered (.upper() and/or look for missing info and/or make
# sure an integer is entrered where only an integer can be entered, etc.)
try:
int(ROOTQtyVar.get())
except:
print "Qty: Must be an integer."
return
# Save to db, or use inputs to make an SQL command for a search, etc.
ROOTNameVar.set("")
ROOTQtyVar.set("")
chgPROGChgBar("ROOT", 0)
print "Done."
return



##################
LFrm = Frame(Root)
ROOTBarSVar = IntVar()
PROGBar["ROOT"] = Frame(LFrm, height = 5)
PROGBar["ROOT"].pack(side = TOP, fill = X, expand = YES, pady = 3)
Sub = Frame(LFrm)
labelEntry(Sub, "Name:", ROOTNameVar, 20)
Sub.pack(side = TOP, pady = 20)
Sub = Frame(LFrm)
labelEntry(Sub, "Qty:", ROOTQtyVar, "Qty", "ROOT")
Sub.pack(side = TOP, padx = 20, pady = 20)
Sub = Frame(LFrm)
Button(Sub, text = "Go", command = rootDoSomething).pack(side = TOP)
Sub.pack(side = TOP)
LFrm.pack(side = TOP)

Root.mainloop()

######################################

It's micro-mini-chunks of code from a 42,000 line inventory and shipping program.

The class does what it needs to do and dovetails in with the rest of the program. So we're telling a View object, the Entry() (you caught me -- trying to learn MVC stuff in iOS/OSX), to control the contents of a Model object, the StringVar(), instead of having model things, functions via .trace(), control the contents of a Model thing, the StringVar(), which would then automagically update the View. Right? Jobs would never approve. He probably wouldn't approve either way.

I might keep it if I can't figure out what happens when you StringVar.trace() on the same variable twice. Using .trace() and just looking at the contents of the StringVar() seems way more straightforward (read non-obfuscated) to me. The only thing that didn't make sense was the lambda. :)

Thanks!