code: public ActionListDialogBuilder addAction(final String label, final Runnable action) {
          return addAction(new Runnable() {
              @Override
              public String toString() {
                  return label;
              }
  
              @Override
              public void run() {
                  action.run();
              }
          });
      }
docs: Adds an additional action to the {@code ActionListBox} that is to be displayed when the dialog is opened
  @param label Label of the new action
  @param action Action to perform if the user selects this item
  @return Itself