Exits the modal window on an escape press.

        :param      event | <QtCore.QKeyPressEvent>

def keyPressEvent(self, event):
        """
        Exits the modal window on an escape press.

        :param      event | <QtCore.QKeyPressEvent>
        """
        if event.key() == QtCore.Qt.Key_Escape:
            self.reject()

        super(XOverlayWidget, self).keyPressEvent(event)