QCustomPlot Discussion and Comments

when I run the example source code of 'interaction-example', i clicked a point of a plot, it became all selected. Then I read the doc in https://www.qcustomplot.com/documentation/dataselection.html
and added the following code to be able to select just a single point.
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for(int i=0; i<ui->customPlot->graphCount(); ++i)
{
ui->customPlot->plottable(i)->setSelectable(QCP::stSingleData);
}
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but the problem is : when i click the point of a plot, always the fisrt point of the plot was became selected.
what i want is just the single (second or the other, but not always the first one) point become selected.
HOW CAN I FIX THIS?

Solved this by comment the line in function MainWindow::selectionChanged last line:
graph->setSelection(QCPDataSelection(graph->data()->dataRange()));