rubberband zooming in QGraphicsView

[seok]

hi community,

somebody help me how to zoom the area selected by rubberband

After setting the drag mode to rubber band drag in QGraphicsview
setDragMode(QGraphicsView::RubberBandDrag)
how to zoom the area selected by the rubber band

Thanks in advance

[seok]

here is the code i have tried so far
but after this i dont know how to make that selected area zoom

    ui->graphicsView->setInteractive(true);

    series = new QScatterSeries();
    scene = new QGraphicsScene(this);
    series->append(0,1);
    series->append(1,2);
    series->append(2,3);
    series->append(5,4);


    chart = new QChart();
    chart->ItemIsSelectable;
    chart->addSeries(series);
    chart->setTitle("chart");
    chart->createDefaultAxes();

    chart->legend()->hide();
    chart->legend()->setAlignment(Qt::AlignTop);
    chart->setMinimumSize(700,300);
    scene->addItem(chart);
   ui->graphicsView->setScene(scene);

   ui->graphicsView->setDragMode(QGraphicsView::RubberBandDrag);

i found about rubberbandchanged() signal but dont know how to use it

[JonB]

@seok
There are lots of Google hits for qgraphicsview rubber band zoom. There is an old thread at https://www.qtcentre.org/threads/12836-Graphics-view-rubberband-zooming which says:

Setting the drag mode as Rubberband drag, you will only be able to select items based on the selection.

To implement the zoom based on rubberband, u will need to implement ur own rubberband.

For this u need to catch the mouse events in scene or view. Based on this, once u get the rectangle after rubberbanding, u just nee to call fitInView() function.

So I don't know if this is what you had in mind. I didn't read through the other hits, but I would if that is what I wanted to achieve.