public boolean isToggleEvent(MouseEvent event)
	{
		// NOTE: IsMetaDown always returns true for right-clicks on the Mac, so
		// toggle selection for left mouse buttons requires CMD key to be pressed,
		// but toggle for right mouse buttons requires CTRL to be pressed.
		return (event != null) ? ((mxUtils.IS_MAC) ? ((SwingUtilities
				.isLeftMouseButton(event) && event.isMetaDown()) || (SwingUtilities
				.isRightMouseButton(event) && event.isControlDown()))
				: event.isControlDown())
				: false;
	}