@Nullable
  @Override
  public Object getData(@NotNull String dataId) {
    if (CommonDataKeys.NAVIGATABLE_ARRAY.is(dataId)) {
      List<Navigatable> navigatables = getNavigatables();
      return navigatables.isEmpty() ? null : navigatables.toArray(Navigatable.EMPTY_NAVIGATABLE_ARRAY);
    }
    if (PlatformDataKeys.TREE_EXPANDER.is(dataId)) {
      return new DefaultTreeExpander(myTree);
    }
    return null;
  }
@Nullable
  @Override
  public Object getData(@NotNull String dataId)