[haiku-development] Re: Scrolling with child views - bug or feature?
- From: "Ingo Weinhold" <ingo_weinhold@xxxxxx>
- To: haiku-development@xxxxxxxxxxxxx
- Date: Fri, 17 Jul 2009 14:28:09 +0200
-------- Original-Nachricht --------
> Datum: Fri, 17 Jul 2009 07:17:50 -0500
> Von: Rene Gollent <anevilyak@xxxxxxxxx>
> On Fri, Jul 17, 2009 at 2:34 AM, Stephan Assmus<superstippi@xxxxxx> wrote:
> > Maybe I am missing something, but from your explaination, I would say
> it's
> > intentional. Why would scrolling the parent view affect something local
> to
> > the child views?
>
> The problem is that means the view has no way of determining its
> viewport. To give an example, if I'm scrolled say, 10% down, the
> parent's bounds are something like (top = 1350, bottom = 1737).
> However, the child view always gives back (top = 0, bottom = 13000),
> which corresponds to the entire range of the scroll bar, regardless of
> the actual scroll position. However, the app_server obviously knows,
> since it gives correct ranges for Draw's update rects, and also
> correctly gives me the appropriate B_EXITED_VIEW / B_OUTSIDE_VIEW
> transits. However, I basically can't determine, without the help of
> the parent bounds rect, where outside my view the mouse pointer lies,
> which is needed to determine the direction to scroll in when drag
> selecting with the mouse. Furthermore, that only works in this case
> because there's a 1:1 correspondence between the height of the child
> and the height of the parent. To me it seems unintuitive at best that
> you're saying the child cannot be self contained in this case. There
> needs to be some way for the child to discover its current viewport.
IIRC outside of Draw() GetClippingRegion() returns the respective region.
CU, Ingo
Other related posts:
