QwtPlot - Copying before using with QwtPlotRenderer

[Maximus2]

I have a custom QwtPlot that I want to render inside a pdf document. (see use-case image)
QwtPlotRenderer looks to be perfect for doing this, the only thing is that I need to edit a few thing on the Plot before rendering it.

Right now I just modify the original plot directly before rendering it, which cause the interface to also be modified.
Here is an example :

void WorkoutCreator::exportWorkoutToPdf() {
 
    /// TODO: Add Title, remove background image, increase margins
    ui->widget_plot->setContentsMargins(20,20,20,20);
 
    QwtPlotRenderer renderer;
    renderer.exportTo( ui->widget_plot, "shapes.pdf" );
 
    /// Revert plot back to normal (best would be to copy to a new QwtPlot and trash it after this function is done..)
    ui->widget_plot->setContentsMargins(0,0,0,0);
 
}

void WorkoutCreator::exportWorkoutToPdf() {

    /// TODO: Add Title, remove background image, increase margins
    ui->widget_plot->setContentsMargins(20,20,20,20);

    QwtPlotRenderer renderer;
    renderer.exportTo( ui->widget_plot, "shapes.pdf" );

    /// Revert plot back to normal (best would be to copy to a new QwtPlot and trash it after this function is done..)
    ui->widget_plot->setContentsMargins(0,0,0,0);

}

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I would like to copy the QwtPlot with all it's objects (it's just a normal QwtPlot with a few QwtPlotShapeItem)
I have tried to code a copy Constructor, but I'm having problem copying the QwtPlotShapeItem.

Is there an easier solution that I'm missing?
Thanks a lot!

[Uwe]

You can't copy widgets ( or QwtPlotItems ). Your only option - beside modify + export + revert of the original one - is to create a second ( invisible ) one.
The plot items could be temporarily attached to the second one and reattached to the first one again, when the export is done.

Uwe

[Maximus2]

Oh nice idea to have a second invisible one!
Thanks Uwe and many thanks for Qwt hopefully I can repay you sometime soon!

This did the trick:

void WorkoutCreator::exportWorkoutToPdf() {
 
    /// ui->widget_plot_report is a copy of ui->widget_plot formatted for reports - widget is setVisible(false)
    ui->widget_plot_report->setTitle(workout.getName());
    ui->widget_plot_report->setContentsMargins(20,20,20,20);
 
    QwtPlotRenderer renderer;
    renderer.exportTo( ui->widget_plot_report, "shapes.pdf" );
}

void WorkoutCreator::exportWorkoutToPdf() {

    /// ui->widget_plot_report is a copy of ui->widget_plot formatted for reports - widget is setVisible(false)
    ui->widget_plot_report->setTitle(workout.getName());
    ui->widget_plot_report->setContentsMargins(20,20,20,20);

    QwtPlotRenderer renderer;
    renderer.exportTo( ui->widget_plot_report, "shapes.pdf" );
}

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