Start recording a key combination when the user clicks on the setButton.
        The button itself is automatically disabled during the recording process.

def on_setButton_pressed(self):
        """
        Start recording a key combination when the user clicks on the setButton.
        The button itself is automatically disabled during the recording process.
        """
        self.keyLabel.setText("Press a key or combination...")  # TODO: i18n
        logger.debug("User starts to record a key combination.")
        self.grabber = iomediator.KeyGrabber(self)
        self.grabber.start()