[PyQt] QValidator raises TypeError

[Phil Thompson]

On Tue, 20 Oct 2009 13:01:01 +0200, Mads Ipsen <mpi at comxnet.dk> wrote:
> I am trying to implement a simple validator for a QLineEdit. To do this 
> you should inherit from QtGui.QValidator and overload the method 
> validate(). The validate method should then return either of the flags:
> 
> QtGui.QValidator.Invalid
> QtGui.QValidator.Intermediate
> QtGui.QValidator.Acceptable
> 
> Below is included a simple example that always returns 
> QtGui.QValidator.Acceptable. Nevertheless, the programs raises the error
> 
>   TypeError: invalid result type from Validator.validate()
> 
> no matter what you type in the line edit.
> 
> Any suggestions?
> 
> Best, Mads
> 
> 
> import sys
> from PyQt4 import QtGui
> 
> class Validator(QtGui.QValidator):
>     def __init__(self, parent=None):
>         QtGui.QValidator.__init__(self, parent)
> 
>     def validate(self, string, pos):
>         return QtGui.QValidator.Acceptable

The Python API is different to the C++ API because the latter updates the
reference to "pos". The Python API needs you to return the (possibly
different) position. Try...

        return (QtGui.QValidator.Acceptable, pos)

Phil