anchor.diff:        widget.source.addListener(_handleDataSourceChanged);
         _handleDataSourceChanged();
       }
  +    if (oldWidget.controller != widget.controller) {
  +      oldWidget.controller?._detach();
  +      widget.controller?._attach(this);
  +    }
     }
   
     @override
  
positive.code: import 'package:flutter/widgets.dart';
  
  import 'data_table_2.dart';
  
  /// In-place replacement of standard [PaginatedDataTable] widget, mimics it API.
  /// Has the header row and paginatior always fixed to top and bottom (correspondingly).
  
negative.code:         widget.initialFirstRowIndex ??
          0;
      widget.source.addListener(_handleDataSourceChanged);
      _effectiveRowsPerPage = widget.rowsPerPage;
      widget.controller?._attach(this);
      _handleDataSourceChanged();
    }
  
  