anchor.diff:  /// those of the same name on [ListTile].
   ///
   /// The [selected] property on this widget is similar to the [ListTile.selected]
  -/// property, but the color used is [activeColor], if it's non-null.
  -/// No effort is made to coordinate the [selected] state and the
  -/// [value] state; to have the list tile appear selected when the
  -/// checkbox is checked, pass the same value to both.
  +/// property, but the color used is that described by [activeColor], if any,
  +/// defaulting to the accent color of the current [Theme]. No effort is made to
  +/// coordinate the [selected] state and the [value] state; to have the list tile
  +/// appear selected when the checkbox is checked, pass the same value to both.
   ///
   /// The checkbox is shown on the right by default in left-to-right languages
   /// (i.e. the trailing edge). This can be changed using [controlAffinity]. The
  
positive.code: 
    /// The color to use when this checkbox is checked.
    ///
    /// If this property is null, then the checkbox's default is used, which is
    /// [ThemeData.toggleableActiveColor].
    final Color? activeColor;
  
    /// The color to use for the check icon when this checkbox is checked.
  
negative.code:         trailing = control;
          break;
      }
      return MergeSemantics(
        child: ListTileTheme.merge(
          selectedColor: activeColor ?? Theme.of(context).accentColor,
          child: ListTile(
            leading: leading,
            title: title,
            subtitle: subtitle,
            trailing: trailing,
            isThreeLine: isThreeLine,
            dense: dense,
            enabled: onChanged != null,
            onTap: onChanged != null ? _handleValueChange : null,
            selected: selected,
            autofocus: autofocus,
            contentPadding: contentPadding,
            shape: shape,
            selectedTileColor: selectedTileColor,
            tileColor: tileColor,
          ),
        ),
      );
    }
  