Hello,
I'm writing an application that uses Qwt 5.2.1 and uses QwtPlot in a QGraphicsView widget. I have a QwtPlotCurve and 1 or two QwtPlotMarker as horizontal lines. I'm trying to add vertical markers as an array of QwtPlotMarker. The first time I add them it works OK:
1..jpg
When I select new points for the markers, I would like remove the old ones but they remain on the plot:
2..jpg
here is the code:
//////// Draw Vertical Markers
void ThresholdDataPlot:rawXMarkers(QList<double> *l)
{
double y;
MarkersX = l;
nXMarkers = MarkersX->count();
VMarks = new QwtPlotMarker *[nXMarkers];

QPen p(Qt::blue);

for(int i = 0; i < nXMarkers; i++)
{
VMarks[i] = new QwtPlotMarker();
VMarks[i]->setLinePen(p);
VMarks[i]->setLineStyle(QwtPlotMarker::VLine);
y = MarkersX->at(i);
VMarks[i]->setXValue(y);
VMarks[i]->attach(this);
}

replot();
}


void ThresholdDataPlot::CleanXMarkers()
{
if(VMarks == NULL) return;

for(int i = 0; i < nXMarkers; i++)
{
VMarks[i]->hide();
VMarks[i]->detach();
delete VMarks[i];
}
delete [] VMarks;

VMarks = NULL;
replot();
}

Any ideas?

Thanks,

Muz