@SuppressWarnings("unchecked")
	public void actionPerformed(ActionEvent e) {
		JComboBox<String> cb = (JComboBox<String>) e.getSource();
		String field = (String) cb.getSelectedItem();
		if (visualisation instanceof OlympicBubbleplot) {
			OlympicBubbleplot s = (OlympicBubbleplot) visualisation;
			// s.setYField(field);
			if (cb == ySelect)
				s.setYField(field);
			else if (cb == xSelect)
				s.setXField(field);
			else if (cb == sizeSelect)
				s.setDataSizeAction(field);
		}
	}