Make the window ``windowObj`` active and focus the first
        applet therein.

        |Args|

        * ``windowObj`` (**QtmacsWindow**): window to activate.

        |Returns|

        * **None**

        |Raises|

        * **QtmacsArgumentError** if at least one argument has an invalid type.

def qteMakeWindowActive(self, windowObj: QtmacsWindow):
        """
        Make the window ``windowObj`` active and focus the first
        applet therein.

        |Args|

        * ``windowObj`` (**QtmacsWindow**): window to activate.

        |Returns|

        * **None**

        |Raises|

        * **QtmacsArgumentError** if at least one argument has an invalid type.
        """

        if windowObj in self._qteWindowList:
            # This will trigger the focusChanged slot which, in
            # conjunction with the focus manager, will take care of
            # the rest. Note that ``activateWindow`` is a native Qt
            # method, not a Qtmacs invention.
            windowObj.activateWindow()
        else:
            self.qteLogger.warning('Window to activate does not exist')