graph or plot widget

Hi,

I'm trying to implement a plot widget based on the chart-widget, but I'm finding
it awkward due to the 'items v. values'layout. What I want is a basic x y plot,
where I can input data-values as coordinates. Is there any way to do this with
the chart-widget (or a sub-class of it)? Or would I have to mess around with the
chart-or-plot superclass?

Thanks,
Chris