docs: protected Filter getFilter() {
          switch (mAutoCompleteMode){
              case AUTOCOMPLETE_MODE_SINGLE:
                  return ((InternalAutoCompleteTextView)mInputView).superGetFilter();
              case AUTOCOMPLETE_MODE_MULTI:
                  return ((InternalMultiAutoCompleteTextView)mInputView).superGetFilter();
              default:
                  return null;
          }
      }