From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=0.7 required=5.0 tests=BAYES_00,INVALID_DATE, MSGID_SHORT,REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!uwvax!astroatc!nicmad!karsh From: karsh@nicmad.UUCP (Bruce Karsh) Newsgroups: comp.windows.x,comp.lang.ada Subject: Re: X and Ada? Message-ID: <1983@nicmad.UUCP> Date: Tue, 15-Sep-87 19:36:37 EDT Article-I.D.: nicmad.1983 Posted: Tue Sep 15 19:36:37 1987 Date-Received: Fri, 18-Sep-87 07:08:00 EDT References: <249@sandia.UUCP> <64@kvasir.esosun.UUCP> <1415@bloom-beacon.MIT.EDU> Reply-To: karsh@nicmad.UUCP (Bruce Karsh) Organization: Nicolet Instruments, Biomedical Division Keywords: Toolkit, Ada, Callback Xref: mnetor comp.windows.x:1425 comp.lang.ada:690 List-Id: In article <1415@bloom-beacon.MIT.EDU> newman@Leo.UUCP (Ron Newman) writes: > >*Any* toolkit is going to depend on the use of call-back functions. I don't agree with this. It bothers me that X has two different mechanisms for sending messages when it would considerably simplify things if only one were used. The X event mechanism is sufficient to handle all the message passing requirements that the callback mechanism handles. I think that X events should be extended and generalized so that they would allow events generated by toolkit gadgets to be handled in the same way that normal X events are handled. For example, if you move a slidebar, the toolkit should generate a SlidebarMoved pseudo X event, which gets queued in the same way that regular X events are queued. Your event loop would handle this pseudo event in the same way that it handles regular X events. There would not have to be special treatment for X events versus X toolkit events. Does anybody know why X has two different kinds of message passing mechanisms? Couldn't we just get rid of call-backs? Does anybody have any ideas on what the "right" message passing mechanism for X should be? [I like the idea that each toolkit gadget should be it's own lightweight process that sends messages to other interested processes whenever its state changes]. -- Bruce Karsh {uwvax,ihnp4}!nicmad!karsh