anchor.diff:    Container buildCell() {
       return Container(
         decoration: BoxDecoration(
  -        color: rootNode.displayColor,
  +        color: widget.rootNode.displayColor,
           border: Border.all(color: Colors.black87),
         ),
         child: Center(
  -        child: height > minHeightToDisplayCellText
  +        child: widget.height > Treemap.minHeightToDisplayCellText
               ? buildNameAndSizeText(
  -                textColor: rootNode.showDiff ? Colors.white : Colors.black,
  +                textColor:
  +                    widget.rootNode.showDiff ? Colors.white : Colors.black,
                   oneLine: false,
                 )
               : const SizedBox(),
  
positive.code:     @required bool oneLine,
    }) {
      return Text(
        rootNode.displayText(oneLine: oneLine),
        style: TextStyle(color: textColor),
        textAlign: TextAlign.center,
        overflow: TextOverflow.ellipsis,
  
negative.code:   }
  
    Widget buildTitleText(BuildContext context) {
      if (widget.isOutermostLevel) {
        return buildBreadcrumbsNavigator();
      } else {
        return buildSelectable(
          child: Container(
            height: Treemap.treeMapHeaderHeight,
            width: double.infinity,
            decoration: BoxDecoration(
              border: Border.all(color: Colors.black87),
  