public RendererOptions() {
    this.setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
    renderers.addItem("Parallel");
    renderers.addItem("Serial");
    renderers.addActionListener(actionProvider.actionDelegate());
    renderers.setSelectedItem("Parallel");

    JPanel upper = new JPanel();
    upper.add(new LabeledItem("Render:", renderers));
    this.add(upper);
  }
 public void addActionListener(ActionListener l) {
   actionProvider.addActionListener(l);
 }