Tk variables problem

[Fredrik Lundh]

<F note="mailed and posted">

Sven Drescher wrote:
> I cannot understand why the following little program doesn't work correct.
> It's surely a little problem, but in my program are more situations, where
> such an error is raised.
/.../
> Attribute Error: 'None' object has no attribute 'tk'

you must create a Tk instance (a root window)
before you can create variables.  creating such
a window initializes the Tk interface, and installs
a default root object.

(if you create a widget, it automagically creates
a root window for you, but image and variable
objects doesn't do that)

</F>

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