tcltk GUIs (was need gui matrix editor: does R Core team have advice on how?)

Dear Paul and Gabor,

The Rcmdr GUI uses the tcltk package, so I have some experience with
providing an R tcltk-based GUI for various platforms.

As Gabor says, everything works very smoothly on Windows because the R
Windows binary includes Tcl/Tk.

Maybe, but getting it there was very far from smooth.  Tcl/Tk compiled 
under the compilers we used, but the resulting DLLs crashed R.  No one 
has ever found the cause and I used the system SDK (essentiallly a 
version of VC++) to build them.  And that puts us in a bind since the 
current system SDKs generate code depending on DLLs that are not part of 
the minimal OS versions we support (e.g. Windows XP and Server 2003, and 
the machine used to build was retired 2 years ago).

On Mac OS X, it's necessary for the user to
install Tcl/Tk for X Windows and to insure that X Windows is installed (as
it typically is in recent releases of Mac OS X). In my experience, most
Linux users already have Tcl/Tk and X Windows (or if they don't, they're
familiar with how to install software on their systems), so that things work
smoothly there as well.

The upshot of this is that Mac OS X is the platform that seems to generate
the most problems for naive users, although installing Tcl/Tk for X Windows
isn't that difficult. Take a look, e.g., at the Rcmdr installation notes
<http://socserv.socsci.mcmaster.ca/jfox/Misc/Rcmdr/installation-notes.html>.

If this were really a problem it could be resolved with far less effort 
than was needed on Windows.  The X11 version of Tk is only needed to get 
R's tcltk to play under R.app.  For those wanting a Tk-based front end 
for command-line R, it is easy to build R against the Tcl/Tk which ships 
with OS X (or an update of it) and get fully Aqua-themed widgets.  If I 
want to show Rcmdr to a Mac user, that is what I use.

As various recent threads on R-sig-mac show, some useRs are capable of 
misconfiguring their Macs so that X11 does not work, does not find any 
fonts ... but maybe they could manage the same on any other Unix-alike.

I hope this helps,
  John

--------------------------------
John Fox
Senator William McMaster
   Professor of Social Statistics
Department of Sociology
McMaster University
Hamilton, Ontario, Canada
http://socserv.mcmaster.ca/jfox

Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595