QChartView *chartWidget= new QChartView();
    chartView->setRenderHint(QPainter::Antialiasing);
    chartView->resize(800, 300);
    chartView->setRubberBand(QChartView::NoRubberBand);
    chartView->setDragMode(QChartView::RubberBandDrag);    

connect(chartWidget,&QChartView::rubberBandChanged,this,[=](QRect viewportRect, QPointF fromScenePoint, QPointF toScenePoint){
        if (viewportRect.isNull()) {//结束选择
            QScatterSeries *series = (QScatterSeries *)chartWidget->chart()->series().first();
            QVector<QPointF> ver = series->pointsVector();
//            qDebug() << "ver="<<ver;

            for (const QPointF &p:ver) {
                if (m_viewportRect.contains(chart_to_view_point(p))) {
                    qDebug() << "ver0 x="<<p.x()<<" y="<<p.y();
                    // emit signal_selected("scatter1",p);
                }
            }

//            Debug() << "ver0 x="<<p.x()<<" y="<<p.y();
//          for (int i = 0 ; i <   series->points().size();i++){
//              qDebug() << "--------------------------    "   << i;
//          }
        }
        else {
            m_viewportRect = viewportRect;
        }
    });


QPoint MainWindow::chart_to_view_point(QPointF char_coord)
{
    QPointF scene_point = chartWidget->chart()->mapToPosition(char_coord);
    QPoint view_point = chartWidget->mapFromScene(scene_point);

    return view_point;
}