Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!tut.cis.ohio-state.edu!att!cbnewsl!dog
From: dog@cbnewsl.ATT.COM (edward.n.schiebel)
Newsgroups: comp.lang.c++
Subject: Re: C++ and SunView
Message-ID: <3811@cbnewsl.ATT.COM>
Date: 24 Jan 90 17:28:15 GMT
References: <1804@unccvax.UUCP>
Distribution: usa
Organization: AT&T Bell Laboratories
Lines: 27

From article <1804@unccvax.UUCP>, by cs00wsc@unccvax.UUCP (Shiang Chin):
> I have a problem when I create applications using
> C++ and SunView. For example, If I define a class:
> 
> [Class A with member function int a(); declared ]
>
> and create a window with some command buttons by using SunView
> library. I assigned the method 'a()' to one of the command
> button as a called back notify procedure. 
You cannot do this.  When SunView calls (), it does not know
what A to call it with.  Remember, a() as a member function is called
as anA.a().  SunView is passing its own parameters in (I think a
notify procedure is called with a Panel_item and an Event*).

> Assumming the value stored in the variable 'a' now
> is 100, when I clicked the mouse on that command button the
> value printed out should be '100', but the value I
> got was not correct. 
It guess was just (a lack of) luck that the program didn't core dump.
When SunView called a(), there is no 'this'.

> Wen S. Chin at UNC Charlotte

	Ed Schiebel
	AT&T Bell Laboratories
	dog@vilya.att.com