public void apply() {
		if (mag_idx == -1)
			return;

		Magnet magnet = (Magnet) PaneData.magnetList.get(mag_idx);
		if (strType.equals("S") && strMeasure.equals("O")) {
			ArrayList repelList = new ArrayList();
			for (int i = 0; i < chkboxList.length; i++) {
				repelList.add(new Boolean(chkboxList[i].isSelected()));
			}
			magnet.setRepelList(repelList);
			magnet.setMagnitude(sliderMag.getValue());
		} else if (strMeasure.compareTo("Q") == 0) {
			magnet.setMagnitude(sliderMag.getValue());
			magnet.setThreshold(sliderRepel.getDoubleValue());
		} else
			assert false;
	}