From: bobhays@spss.com (Bob Hays)
Newsgroups: fj.mail-lists.x-window
Subject: Re: XVT toolkit??
Date: 20 Nov 92 02:17:24 GMT
Distribution: fj
Organization: SPSS, Inc.

Date: Wed, 11 Nov 1992 15:43:37 GMT
Message-Id: <1992Nov11.154337.2143@spss.com>
Newsgroups: comp.windows.x,comp.windows.x.motif,comp.windows.misc,comp.sys.misc,comp.sys.mac.misc,comp.unix.misc

In article <TODD.92Nov11072401@todd.kastle.com>, todd@kastle.com (Todd A. Scalzott) writes:
> In article <BxCptF.Jw1@world.std.com> kevyn@world.std.com (Kevyn Ford) writes:
> 
> >   Newsgroups: comp.windows.x,comp.windows.x.motif,comp.windows.misc,comp.sys.misc,comp.sys.mac.misc,comp.unix.misc
> >   Path: friend!uunet!pageworks.com!world!kevyn
> >   From: kevyn@world.std.com (Kevyn Ford)
> >   Organization: The World Public Access UNIX, Brookline, MA
> >   References: <1992Nov6.173238.6810@atinc.uucp>
> >   Date: Sat, 7 Nov 1992 15:03:13 GMT
> >
> >   > I would like inputs from anyone who has used the XVT Portability
> >   > Toolkit.
> >
> >   One of my projects evaluated the XVT Toolkit against using the native
> >   GUI for our VAXstations ... as far as producing a portable GUI
> >   application XVT is fairly good.
> Agreed.  I haven't had to do any ports yet (the project has gone to the
> wayside), but I really like XVT.  Especially over the straight X or Motif
> programming.

I would strongly suggest porting from UNIX (OSF/Motif or OpenLook)
instead of to them.  XVT's event model is a combination of linear and
event-driven, and X is almost entirely (if not entirely) event driven.
This can cause problems in startup and init code for windows.

> >   However, while there wasn't any one problem that we encountered with
> >   XVT, it is not as robust as the native GUI system (which is to be
> >   expected) and we found that there were many "small" features lacking
> >   that, all together, gave the application an "unfinished" look (you can
> >   actually see some of this in their XVT-Design tool itself -- which is
> >   brain-dead).
> That's what the "eXtensible" in XVT is for.  You are NOT limitted to the
> API.  In fact, the API provides a nice set of conditionals upon which you
> build your native code.  

First, we've found numerous problems with XVT - some have been
repaired, some will be repaired later, and some are the way they want
it to work (which is okay by me, BTW).

Unfortunately, XVT does not provide some extension hooks you might
like, so your mileage may vary....  Look carefully at what you want
before you buy (as always, caveat emptor applies).  We have a source
license and we have made significant changes to support a more
OSF/Motif and Windows (as appropriate, I hope:-) look-and-feel.  As it
comes from the box, for instance, XVT does not support pointer focus
on OSF/Motif....
 
> >   We have found that XVT is more suited for "simpler" interfaces, and it
> >   will be used as such, but for one particular application we've decided
> >   to use the DECwindows/Motif interface.
> >
> >   In short, XVT is a good portable GUI system for apps that don't really
> >   need anything more than a few pull-down menus and graphical controls.
> I don't really agree with this, although I see where you are coming from.
> Question:  are you using release 2, or release 3?  If you haven't looked at
> release 3 yet, it is a major improvement over the release 2 API and
> provides new types of controls (whose popularity came about with the advent
> of Windows 3.1).  

We use XVT V. 3 and I agree with the former statement.  I don't think
I would bet my development of a large, complex program on XVT right
now (perhaps at V. 4 they will have knocked off the major problems
like portable font support [font mapper is a joke - people on X will
expect to use X fonts and colors], X resource handling, etc., and
perhaps some of the issues we've had with Windows [although to their
credit our Windows people say that 3.0 is much better than 2.x).

The above lines without the '>'s are my opinion only - I've been using
XVT on a large application for 1 1/2 years now, so your mileage again
may vary.  My opinion is that XVT wishes to force some general rules
on application behavior and this is not always consistent with the
target platform GUI.

Have fun! - Bob

-- 
===============================================================================
The opinions expressed above are those of Bob Hays and not SPSS, Inc.
 bobhays@spss.com  Phone: (312) 329-3529 | "I'm hovering like a fly, waiting
                   Fax:   (312) 329-3657 |  for a windshield on a freeway" -PG