class ItemGroup extends AbstractItemHierarchy implements ItemInflater.ItemParent, ItemHierarchy.Observer {

  public void clear() {
    if (children.isEmpty()) {
      return;
    }

    final int numRemoved = getCount();

    for (ItemHierarchy item : children) {
      item.unregisterObserver(this);
    }
    dirty = true;
    children.clear();
    notifyItemRangeRemoved(0, numRemoved);
  }

  public  ItemGroup();
  public  ItemGroup(Context context, AttributeSet attrs);

}