anchor.diff:    /// you can override it with your custom data.
     /// /// [show] determines showing label or not.
     HorizontalLineLabel({
  -    EdgeInsets padding = const EdgeInsets.all(6),
  -    TextStyle style = const TextStyle(
  -      color: Colors.black,
  -      fontWeight: FontWeight.bold,
  -      fontSize: 14,
  -    ),
  -    Alignment alignment = Alignment.topLeft,
  +    EdgeInsets padding,
  +    TextStyle style,
  +    Alignment alignment,
       bool show = false,
  -    this.labelResolver = HorizontalLineLabel.defaultLineLabelResolver,
  -  }) : super(show: show, padding: padding, style: style, alignment: alignment);
  +    String Function(HorizontalLine) labelResolver,
  +  })
  +    : labelResolver = labelResolver ?? HorizontalLineLabel.defaultLineLabelResolver,
  +      super(
  +      show: show,
  +      padding: padding ?? const EdgeInsets.all(6),
  +      style: style ?? const TextStyle(
  +        color: Colors.black,
  +        fontWeight: FontWeight.bold,
  +        fontSize: 14,
  +      ),
  +      alignment: alignment ?? Alignment.topLeft,
  +    );
   
     /// Lerps a [HorizontalLineLabel] based on [t] value, check [Tween.lerp].
     static HorizontalLineLabel lerp(HorizontalLineLabel a, HorizontalLineLabel b, double t) {
  
positive.code:   /// and you can implement [getStrokeColor] callback,
    /// it gives you the [FlSpot], and you should decide to return a [Color].
    FlDotData({
      this.show = true,
      this.dotSize = 4.0,
      this.checkToShowDot = showAllDots,
      this.strokeWidth = 0.0,
      this.getStrokeColor = _defaultGetDotStrokeColor,
      this.getDotColor = _defaultGetDotColor,
    });
  
    /// Lerps a [FlDotData] based on [t] value, check [Tween.lerp].
    static FlDotData lerp(FlDotData a, FlDotData b, double t) {
  
negative.code:   /// you can customize the appearance of the lines using [flLineStyle]
    /// and you can decide to show or hide the lines on each spot using [checkToShowSpotLine].
    BarAreaSpotsLine({
      bool show,
      FlLine flLineStyle,
      CheckToShowSpotLine checkToShowSpotLine,
    })
      : show = show ?? false,
        flLineStyle = flLineStyle ?? const FlLine(),
        checkToShowSpotLine = checkToShowSpotLine ?? showAllSpotsBelowLine;
  
    /// Lerps a [BarAreaSpotsLine] based on [t] value, check [Tween.lerp].
    static BarAreaSpotsLine lerp(BarAreaSpotsLine a, BarAreaSpotsLine b, double t) {
  