Plots and Layouts

[rambo83]

Ok, I have solved it myself by inserting the QwtPlot into a layout:

QVBoxLayout * layout_plot = new QVBoxLayout(ui_frame_for_plot);
 
	// build object of class "Plot", which will plot the 2D surfaces
	d_plot = new Plot();
	layout_plot->addWidget(d_plot);
	d_plot->showSpectrogram(true);

QVBoxLayout * layout_plot = new QVBoxLayout(ui_frame_for_plot);

	// build object of class "Plot", which will plot the 2D surfaces
	d_plot = new Plot();
	layout_plot->addWidget(d_plot);
	d_plot->showSpectrogram(true);

To copy to clipboard, switch view to plain text mode 

Now the plot is displayed.