AttributeError: 'NoneType' object has no attribute '_dial'

by Martin Fitzpatrick Last updated PyQt5 FAQ
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anonymous | 2020-05-11 09:21:56 UTC | #1

When I try running demo I get the following error

python 
dial = self.parent()._dial
AttributeError: 'NoneType' object has no attribute '_dial'

I am running on Windows.

https://www.pythonguis.com/courses/custom-widgets/creating-your-own-custom-widgets/

Virginia | 2020-05-12 14:19:00 UTC | #2

I had this error too, and it turned out it was because I put the paint event in the PowerBar class instead of the _Bar class.

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Martin Fitzpatrick

AttributeError: 'NoneType' object has no attribute '_dial' was written by Martin Fitzpatrick.

Martin Fitzpatrick has been developing Python/Qt apps for 8 years. Building desktop applications to make data-analysis tools more user-friendly, Python was the obvious choice. Starting with Tk, later moving to wxWidgets and finally adopting PyQt. Martin founded PythonGUIs to provide easy to follow GUI programming tutorials to the Python community. He has written a number of popular Python books on the subject.

AttributeError: 'NoneType' object has no attribute '_dial' was published in faq on (updated ) . Feedback & Corrections can be submitted here.

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