  
  class ChartView : public QChartView {
    Q_OBJECT
  
  public:
    ChartView(QChart *chart, QWidget *parent = nullptr) : QChartView(chart, parent) {}
    void mouseReleaseEvent(QMouseEvent *event) override;
  };
  
  class ChartWidget : public QWidget {
  Q_OBJECT
  
 
</s> remove class ChartView : public QChartView {
  Q_OBJECT
 </s> add   void updateSeries();
  void rangeChanged(qreal min, qreal max);
  void updateAxisY();
  void updateState(); </s> remove   void paintEvent(QPaintEvent *event) override;
  double x_pos = -1;
};
 </s> add   void mouseReleaseEvent(QMouseEvent *event) override;
  void mouseMoveEvent(QMouseEvent *ev) override;
  void enterEvent(QEvent *event) override;
  void leaveEvent(QEvent *event) override; </s> remove class LineMarker : public QWidget {
Q_OBJECT
 </s> add class ChartView : public QChartView {
  Q_OBJECT </s> remove   LineMarker(QWidget *parent) : QWidget(parent) {}
  void setX(double x);
 </s> add   ChartView(const QString &id, const QString &sig_name, QWidget *parent = nullptr); </s> remove   LineMarker *line_marker = nullptr;
  QList<QPointF> vals;
 </s> add 
  QGraphicsLineItem *track_line;
  QGraphicsSimpleTextItem *value_text;
  QGraphicsLineItem *line_marker;
  QList<QPointF> vals;
  QString id;
  QString sig_name;
  
  class ChartView : public QChartView {
    Q_OBJECT
  
  QGraphicsLineItem *track_line;
  QGraphicsSimpleTextItem *value_text;
  QGraphicsLineItem *line_marker;
  QList<QPointF> vals;
  QString id;
  QString sig_name;
  QGraphicsLineItem *track_line;
  QGraphicsSimpleTextItem *value_text;
  QGraphicsLineItem *line_marker;
  QList<QPointF> vals;
  QString id;
  QString sig_name;
  QGraphicsLineItem *track_line;
  QGraphicsSimpleTextItem *value_text;
  QGraphicsLineItem *line_marker;
  QList<QPointF> vals;
  QString id;
  QString sig_name;
  };
  
  class ChartWidget : public QWidget {
  Q_OBJECT
  
keep keep keep keep replace replace replace keep keep keep keep keep
 Cabana: display the (x,y) values while MouseMove on the chart (#26064) 
tools/cabana/chartswidget.h