anchor.diff:  
           final double bottomChartPadding = getExtraNeededVerticalSpace() - getTopOffsetDrawSize();
           final Offset to =
  -        Offset(getPixelX(line.x, chartUsableSize), viewSize.height - bottomChartPadding);
  +            Offset(getPixelX(line.x, chartUsableSize), viewSize.height - bottomChartPadding);
   
           extraLinesPaint.color = line.color;
           extraLinesPaint.strokeWidth = line.strokeWidth;
   
           canvas.drawDashedLine(from, to, extraLinesPaint, line.dashArray);
  +
  +        if (line.label != null) {
  +          final VerticalLineLabel label = line.label;
  +          final TextStyle style = TextStyle(fontSize: 11, color: line.color).merge(label.style);
  +          final EdgeInsets padding = label.padding ?? EdgeInsets.zero;
  +
  +          final TextSpan span = TextSpan(
  +            text: label.labelResolver(line),
  +            style: style,
  +          );
  +
  +          final TextPainter tp = TextPainter(
  +            text: span,
  +            textDirection: TextDirection.ltr,
  +          );
  +
  +          tp.layout();
  +
  +          tp.paint(
  +            canvas,
  +            label.alignment.withinRect(
  +              Rect.fromLTRB(
  +                to.dx - padding.right - tp.width,
  +                from.dy + padding.top - topChartPadding,
  +                from.dx + padding.left,
  +                to.dy - padding.bottom + bottomChartPadding,
  +              ),
  +            ),
  +          );
  +        }
         }
       }
     }
  
positive.code: 
          final double rightChartPadding = getExtraNeededHorizontalSpace() - getLeftOffsetDrawSize();
          final Offset to =
          Offset(viewSize.width - rightChartPadding, getPixelY(line.y, chartUsableSize));
  
          extraLinesPaint.color = line.color;
          extraLinesPaint.strokeWidth = line.strokeWidth;
  
          canvas.drawDashedLine(from, to, extraLinesPaint, line.dashArray);
        }
      }
  
  
negative.code: import 'dart:ui' as ui;
  import 'dart:ui';
  
  import 'package:fl_chart/fl_chart.dart';
  import 'package:fl_chart/src/chart/base/axis_chart/axis_chart_data.dart';
  