anchor.diff:    }
   
     BarTouchCallback? _touchCallback;
  +
     set touchCallback(BarTouchCallback? value) {
       _touchCallback = value;
     }
  
positive.code:   }
  
    BarTouchedSpot? _lastTouchedSpot;
  
    @override
    void performLayout() {
  
negative.code: }
  
  /// Renders our BarChart, also handles hitTest.
  class RenderBarChart extends RenderBox implements MouseTrackerAnnotation {
    RenderBarChart(
        BarChartData data, BarChartData targetData, double textScale, BarTouchCallback? touchCallback)
        : _data = data,
  