How do I dynamically adjust the position of QwtPlotMarker using mouse click & drag ?

[sonulohani]

hey, you have already plotted that curve, so now Symbol by the click of mouse, for that use---->

initialize this

QwtPlotMarker *mark[1000];
int i=0;
QPoint pt;

QwtPlotMarker *mark[1000];
int i=0;
QPoint pt;

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void mousePressEvent(QMouseEvent *event){
   mark[i]=new QwtPlotMarker;
   mark[i]->setSymbol(your_symbol);
   mark[i]->setValue(pt.x(),pt.y());
   mark[i]->attach(your_plot);
   i++;
}

void mousePressEvent(QMouseEvent *event){
   mark[i]=new QwtPlotMarker;
   mark[i]->setSymbol(your_symbol);
   mark[i]->setValue(pt.x(),pt.y());
   mark[i]->attach(your_plot);
   i++;
}

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Now wherever you click on the curve it will plot it.