qtgui.py

qtgui.py

    restart_code = 1000
    
    @staticmethod
    def application_main():
        """
        The application's main function. 
        Create application and main window and run them.
        """
        while True:
            app = QApplication(sys.argv)
            window = GuiMain()
            window.show()
            ret = app.exec_()
            print ret
            if ret != GuiMain.restart_code:
                break

When I call QApplication.exit(GuiMain.restart_code) the application terminates with exit value: 134, and message:

QWidget: Must construct a QApplication before a QPaintDevice

I think QApplication can't be restarted.