Re: move_panel and getbegxy

[Bryan Christ]

I'm not really a fan of the keeping the bug for compatibility, but I 
understand it.  Your solution below considers only ncurses.  The problem 
is that if the bug exists in pcurses and curses, then you have 
portability problems.  In other words, its best if curses, pcurses, and 
ncurses all behave the same (even in the ways they are broke).

Clive Nicolson wrote:
> On Thu, 24 May 2007, Bryan Christ wrote:
>
> > This is a bug which Thomas and I discussed sometime ago.  You'll 
> > basically have to move the subwin yourself.  A sample is below.
> >
> > Thomas may have the other half of this email, I can't seem to find the 
> > follow up, but at least this will clear things up for you a bit. 
> > Basically, even though its a bug, other implementations of curses have 
> > this problem and so to fix it would break compatibility.
>
> Your code snippet below fixed both my problems.
>
> I do not support the compatibility idea, once getbegxy returns the wrong 
> value the caller can not fix the values. Without private curses data it 
> is not possible, even then a general fix by the caller is very difficult.
>
> If there is some case I've missed ncurses could offer the user a runtime
> switch to fix the problem.
>
> eg
>
> #ifdef NCURSES_VERSION_PATCH
> #if NCURSES_VERSION_PATCH >= 20070525
>   ncurses_hacks_on(XX_FIX_MOVE);
> #endif
> #endif
>
> I'm prepared to try knocking up a patch to ncurses for this bug.
>
> Thanks
> Clive
>
> > On Wed, 31 May 2006, Christ, Bryan wrote:
> >
> > Thomas,
> >
> > menu_driver() reads window->_begx and window->_begy when determining the
> > appropriate region/coordinates to update.  The problem with this is that
> > _begx and _begy don't get updated if the window is a subwin/derwin and
> > the parent is moved.  the outdated coords cause the mouse hit-test
> > processed by menu_driver() to fail.  why can't this bug be fixed so that
> > menu_driver calculates the offset?  currently i am hacking changes to my
> > subwins (and subwins of subwins of subwins...) to reflect the new data.
> > code snippet below:
> >
> > x=0;
> > y=0;
> >
> > subwin=child_of_window_that_was_moved;
> > while(subwin->_parent!=NULL)
> > {
> >  x+=subwin->_parx;
> >  y+=subwin->_pary;
> >  subwin=subwin->_parent;
> > }
> > x+=subwin->_begx;
> > y+=subwin->_begy;
> >
> > subwin=child_of_window_that_was_moved;
> > subwin->_begy=y;
> > subwin->_begx=x;
> >
> > Clive Nicolson wrote:
> > > I am using ncurses-5.6 .
> > >
> > > I have a panel who's window is associated with a menu (for which I 
> > > provided
> > > a subwindow via derwin).
> > >
> > > I move the panel with move_panel and then do a getbegxy on both the 
> > > window
> > > and the menu's subwindow, the coordinate pairs returned indicate that 
> > > the subwindow has not moved, but that the window has!
> > >
> > > Is this expected?
> > >
> > > I also note that the menu_driver can no longer select items (with the 
> > > mouse)
> > > on the moved menu!
> > >
> > > Clive
> > >
> > >
> > >
> > > _______________________________________________
> > > Bug-ncurses mailing list
> > > address@hidden
> > > http://lists.gnu.org/mailman/listinfo/bug-ncurses