.parent() vs. parent class in PowerBar example

by Martin Fitzpatrick Last updated PyQt5 FAQ
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Jerry_Zhou | 2020-05-11 09:20:01 UTC | #1

I don't understand how the class _Bar can get access to the QDial() object defined in the PowerBarclass by using self.parent(). Shouldn't self.parent()be referring to QWidget, the class it is inheriting from?

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

Jerry_Zhou | 2020-05-15 14:50:20 UTC | #2

Nevermind! Turns out parent() in Qt has different relationship then superclass to subclass. Instead it is between object instances, and when _Bar is instantiated within PowerBar, the parent() of _Bar refers to the Powerbar class.

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.parent() vs. parent class in PowerBar example 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.

.parent() vs. parent class in PowerBar example was published in faq on (updated ) . Feedback & Corrections welcome in our public issue tracker.

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