Path: utzoo!utgpu!watmath!att!ucbvax!tut.cis.ohio-state.edu!bloom-beacon!EXPO.LCS.MIT.EDU!kit
From: kit@EXPO.LCS.MIT.EDU (Chris D. Peterson)
Newsgroups: comp.windows.x
Subject: Re: Subclassing the Athena Widgets
Message-ID: <8908071613.AA15432@expo.lcs.mit.edu>
Date: 7 Aug 89 16:13:19 GMT
References: <9975@csli.Stanford.EDU>
Sender: daemon@bloom-beacon.MIT.EDU
Organization: The Internet
Lines: 31


> For example, I wanted a Toggle widget...

One will be avaliable in Xaw in Release 4.  This Toggle Widget will
do all you want and more :-)

> The new routines in Toggle need to call functions which are private to the
> Command widget (for example, Redisplay).

That is not actually necessary, Other than fixing a couple of bugs in the
Command widget I was able to subclass the Toggle without using any of the 
Command widget`s private functions.  I did, however, need to get at the command
widget`s action routines.  While these should be Publically avaliable there
is a bug in the MIT R3 Intrinsics that makes this impossible, this will
also be fixed in the next release.

> Are there any clean solutions to this problem?  If not, which of the
> above ugly solutions should I pick (should Toggle be a subclass of
> Label or Command?)

As I said I had only a few minor problems subclassing Toggle off of Command,
so if you can`t wait for R4 then I would suggest subclassing off of Command.


						Chris D. Peterson     
						MIT X Consortium 

Net:	 kit@expo.lcs.mit.edu
Phone:   (617) 253 - 9608	
Address: MIT - Room NE43-213