Communication between MainWindow and a dialog

[Backslash]

I'm sorry, but I don't quite understand what doing a cast means.

The MainWindow instance is called mainWin (from main.cpp)

QApplication app(argc, argv);
    MainWindow mainWin;
    mainWin.show();
    return app.exec();

QApplication app(argc, argv);
    MainWindow mainWin;
    mainWin.show();
    return app.exec();

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So do you mean for me to write:

((MainWindow*)parent())->resetKey(K2);

or something else entirely?

Thanks,
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