// Set up the substance selector box
 private void setUpList() {
   List s = system.getSubstances();
   for (Object o : s) {
     Substance sub = (Substance) o;
     substanceBoxModel.addElement(sub.getName());
   }
 }
 public DoseObjectiveEditor(
     JFrame jf, ParameterSearchDoseResponseEditor e, TargetDoseObjective tdo) {
   this(jf, e);
   metric = tdo.getMetric();
   substance = metric.getSubstance();
   substanceSelector.setSelectedItem(substance.getName());
   objective = tdo.getObjective();
   weightField.setText((new Double(tdo.getWeight())).toString());
   updateTarget();
 }