I've just got to stop using one letter for variables, especially ones
that sound alike! :-) Other than v tracking every value change made, did I gain anything by using it? It seems to me that control variables are of marginal use. I might have thought they were necessary for use with scale widgets, but I'm looking at an example that says otherwise. Can you easily construct a simple example where they are absolutely necessary, or at least provide a situation where they are necessary? Kent Johnson wrote: On Fri, Mar 6, 2009 at 7:15 AM, Wayne Watson <sierra_mtnv...@sbcglobal.net> wrote:Control variables. What is the difference between IntVar, BooleanVar, StringVar, and DoubleVar?The difference is the type of value returned by get().For example, in the program below, it looks like I get the same result usint IntVar or StringVar. It almost appears the usage depends on what widget one uses: Entry, RadioButton, CheckBox, ... ===================begin========= from Tkinter import * # Use of control variables def mycallback(): print "User entered:" , e.get() print "Operationg by 2 gives: ", e.get()*2Change the above to use v.get(). e.get() has nothing to do with the var.master = Tk() v=StringVar() #v=IntVar() print v,type(v)Try this: print v, type(v), type(v.get()) Kent --
Wayne Watson (Watson Adventures, Prop., Nevada City, CA) (121.01 Deg. W, 39.26 Deg. N) GMT-8 hr std. time) “In mathematics you don't understand things. You just get used to them.” -- John Von Neumann (P.S. The same is true in life.) Web Page: <www.speckledwithstars.net/> |
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