> I am learning Python 2.4 with Tkinter. I have a series of radio buttons > that I want to bind to their own individual listbox in order to narrow > down a selection process.
Hi Joe, Ok, are you familiar with callbacks? According to: http://www.pythonware.com/library/tkinter/introduction/x6969-patterns.htm you can introduce a callback that will fire off when the user does a Radiobutton selection. Do you have much experience using functions as values? > I just don't seem to grasp how to call up the approiate box to it's > proper radiobutton. If the "callback" we bind to to the radio button could only remember the listbox, we'd be in business. It turns out that this is possible if we build a function within a function: #################### def make_adder(n): def f(x): return x + n return f #################### For example: ######################### >>> add1 = make_adder(1) >>> sub1 = make_adder(-1) >>> add1(3) 4 >>> sub1(3) 2 ######################### This mechanism (lexical scope) is very useful, especially in GUI programming. In your problem, one could imagine making a a function that takes in a listbox and returns a new Radiobutton that "remembers" its listbox. ######################################################## def makeRadioButtonWithListbox(root, listbox): def callback(): # ... This callback has access to the listbox b = Radiobutton(root, text="text", command=callback) return b ######################################################## It's the same technique. In this way, we can create radio buttons that have a way of getting at the listbox. _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
