toplevel class, boxes and scrollbars

[andrewray]

I've been thinking about how to provide scrollbars for widget containers.

It seems some of the functionality currently hidden in the toplevel widget would be needed - stuff like allocation calculation, picking for mouse clicks, finding focus and possibly more.

I wonder if the toplevel, scrollable containers and maybe also layers might all share some functionality which could be factored out into a root widget or class interface.

If that's useful to do more advanced widget, I'm for it. Would that break the exposed API in any way? Like for instance the user having to provide a root widget to run?