Tickering Everywhere

Its been a while since my original LWUIT ticker list post and quite a few has changed, back when I originally posted there was no built in tickering functionality in LWUIT itself. Recent questions in the mailing list and from partners prompted me to write the code bellow, generally for tickering a ComboBox however I tried to make it as generic as possible so it can be installed into every list out there.

Notice that to ticker custom components you need to set them as a cell renderer to prevent the label from throwing an exception when invoking startTicker. You can use the TickerRenderer bellow with practically every list and it doesn't need to be a part of a combo box.

public class TickerComboDemo extends MIDlet {
  public void startApp() {
      try {
          Display.init(this);
          Resources r = Resources.open("/javaTheme.res");
          UIManager.getInstance().setThemeProps(r.getTheme(r.getThemeResourceNames()[0]));
          Form form = new Form("Ticker Combo");
          ComboBox combo = new ComboBox(new String[]{"Jack",
                  "Name that should probably trigger a ticker",
                "Another name that should probably trigger a ticker",
                "Kate", "Sawyer", "Sayid", "Hurley", "Jin", "Sun", "Charlie", "Claire", 
                "Aaron", "Michael", "Walt", "Boone", "Shannon", "Locke", "Mr. Eko",
                "Ana-Lucia", "Libby", "Desmond", "Benjamin Linus", "Juliet Burke"}) {
              protected List createPopupList() {
                  List l = super.createPopupList();
                  l.setListCellRenderer(new TickerRenderer());
                  return l;
              }
          };
          form.addComponent(combo);
          form.show();
      } catch (IOException ex) {
          ex.printStackTrace();
      }
  }

  class TickerRenderer extends DefaultListCellRenderer {
      private DefaultListCellRenderer selectedRenderer = new DefaultListCellRenderer(false);
      private List parentList;
      public TickerRenderer() {
          super(false);
      }

      public boolean animate() {
          if(parentList != null && parentList.getComponentForm() != null) {
              if(selectedRenderer.isTickerRunning()) {
                  if(selectedRenderer.animate()) {
                      parentList.repaint();
                  }
              }
          }
          return super.animate();
      }

      public Component getListCellRendererComponent(List list, Object value, int index, boolean isSelected) {
          if(isSelected) {
              selectedRenderer.getListCellRendererComponent(list, value, index, isSelected);

              // sometimes the list asks for a dummy selected value for size calculations and this might
              // break the tickering state
              if(index == list.getSelectedIndex()) {
                  if(selectedRenderer.shouldTickerStart()) {
                      if(!selectedRenderer.isTickerRunning()) {
                          parentList = list;
                          list.getComponentForm().registerAnimated(this);
                          selectedRenderer.startTicker(UIManager.getInstance().getLookAndFeel().getTickerSpeed(), true);
                      }
                  } else {
                      if(selectedRenderer.isTickerRunning()) {
                          selectedRenderer.stopTicker();
                      }
                  }
              }
              return selectedRenderer;
          } else {
              return super.getListCellRendererComponent(list, value, index, isSelected);
          }
      }
  }

  public void pauseApp() {
  }

  public void destroyApp(boolean unconditional) {
  }
}