@Override
 public void addChoice(String id, String label, String targetView, ViewActivateHandler handler) {
   viewContainer.showView(targetView, id, null);
   viewContainer.getTab(id).setLabel(label);
   View view = viewContainer.getView(id);
   view.addViewActivateHandler(handler);
 }
 private Widget getButton() {
   return View.of(this).getWidget("btnParseDate");
 }
 private MaskedTextBox getDateInput() {
   return View.of(this).getWidget("dateInput", MaskedTextBox.class);
 }