code: public void select(final boolean considerSelectableFlag) {
          mFastAdapter.recursive(new AdapterPredicate<Item>() {
              @Override
              public boolean apply(@NonNull IAdapter<Item> lastParentAdapter, int lastParentPosition, Item item, int position) {
                  select(lastParentAdapter, item, -1, false, considerSelectableFlag);
                  return false;
              }
          }, false);
          mFastAdapter.notifyDataSetChanged();
      }
docs: select all items
  
  @param considerSelectableFlag true if the select method should not select an item if its not selectable