Plot Picker x=0

[sun]

Hi,

I have now integrated a PlotPicker in my QwtPlot and coded a function which should set the picked x and y location in two QLabes:

void MainWindow::valuePlotPickerSelected( const QwtDoublePoint& point)
{
	QString temp; temp.setNum(point.x());
	valuePlotX->setText(temp); temp.setNum(point.y());
	valuePlotY->setText(temp);
}

void MainWindow::valuePlotPickerSelected( const QwtDoublePoint& point)
{
	QString temp; temp.setNum(point.x());
	valuePlotX->setText(temp); temp.setNum(point.y());
	valuePlotY->setText(temp);
}

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This seems to work most of the time. But when I don't replot or even sometimes when i replot it sets the x value to 0.
Y value is allways correct, but I sometimes can pick many points and it is sheer luck if the x value is correct or 0.

What could the problem be? Is it a problem, that there can be less x values than I have pixels on the QwtPlot?

Thanks for taking the time!
sun