Validating Entry in tkinter

[Giacomo Boffi]

Saul Spatz <saul.spatz at gmail.com> writes:

> In tcl/tk an Entry widget can be set to validate its contents with
> the validate option. [...]  Can one do something like this in
> tkinter?

i read the thread and nobody mentioned the python mega widget (Pmw)
toolkit, from whose docs i quote the following

Pmw.EntryField() - entry widget with validation

    [...]

    Validation is performed early, at each keystroke or other event
    which modifies the text. However, if partially valid text is
    permitted, the validity of the entered text can be checked just
    before it is to be used, which is a form of late validation.

    [...]