public ViewModelMergeFeatures(T selectedFeatures, int[] keyOrdinals, int incidOrdinal,
                               HluDataSet.incid_mm_polygonsRow[] childRows, GISApp gisApp)
 {
     _selectedFeatures = selectedFeatures;
     _keyOrdinals      = keyOrdinals;
     _childRows        = childRows;
     _incidOrdinal     = incidOrdinal;
     _gisApp           = gisApp;
 }