anchor.diff:        ),
       );
   
  -    overlayState.insert(hoverOverlayEntry);
  +    overlayState.insert(_hoverOverlayEntry!);
     }
   
     void hideHover() {
  -    if (hoverOverlayEntry != null) {
  -      eventChartController.tapLocation.value = null;
  -      vmChartController.tapLocation.value = null;
  -      androidChartController.tapLocation.value = null;
  -
  -      hoverOverlayEntry?.remove();
  -      hoverOverlayEntry = null;
  +    if (_hoverOverlayEntry != null) {
  +      _eventChartController.tapLocation.value = null;
  +      _vmChartController.tapLocation.value = null;
  +      _androidChartController.tapLocation.value = null;
  +
  +      _hoverOverlayEntry?.remove();
  +      _hoverOverlayEntry = null;
       }
     }
   
  
positive.code: 
      List<Widget> hoverPartImageLine(
        String name, {
        String image,
        Color colorPatch,
        bool dashed = false,
        double leftEdge = 5.0,
      }) {
  
negative.code:       }
      }
  
      final OverlayState overlayState = Overlay.of(context)!;
      _legendOverlayEntry ??= OverlayEntry(
        builder: (context) => Positioned(
          top: position.dy + box.size.height + legendYOffset,
          left: position.dx - legendWidth + box.size.width - legendXOffset,
          height: _controller.isAndroidChartVisible
              ? legendHeight2Charts
              : legendHeight1Chart,
          child: Container(
  