Selecting a QwtPlotCurve and sublcasses in a QwtPlot

Hello!

I have a QwtPlot and on it a may both draw normal QwtPlotCurve items as well as derived classes from them. This items may be alone, by themselves, or they may be a figure construction (for example, a channel figure made of two parallel QwtPlotCurves form a unique item).

Once draw (no problems here), I need to give the user the possibility of selecting (and highlighting the selection by making the curve more thick/fat) both simple curves, derivatives or the entire object made of some curves when only one of them is clicked, but I'm having problems with learning how to do this (and in a efficient way).

I know that there are two examples in the Qwt example libs, event_filter (which is outdated, as far as I remember reading Uwe's comments about it) and itemeditor, that give some hints about selecting and moving drawed objects inside a QwtPlot, but for now I've being uncapable of doing this selection stuff. Particularly, I'm not sure how could I identify a composed object (one made of some QwtPlotCurves) when one of its items is selected.

Could somebody please give me some hints about this? Remember that it should be as efficient as possible. I'm glad for any help.

Thanks,

Momergil

Note: a working code is always preferable ^^