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From: liemandt@lindy.Stanford.EDU (Joe Liemandt)
Newsgroups: comp.sys.next
Subject: Re: Power-Off message to Apps
Message-ID: <5844@lindy.Stanford.EDU>
Date: 17 Nov 89 09:54:01 GMT
Article-I.D.: lindy.5844
References: <6694@portia.Stanford.EDU> <12846@polya.Stanford.EDU>
Sender: news@lindy.Stanford.EDU (News Service)
Reply-To: liemandt@lindy.Stanford.EDU (Joe Liemandt)
Organization: Stanford University
Lines: 86

In article <12846@polya.Stanford.EDU> ali@Polya.Stanford.EDU (Ali T. Ozer) writes:
>In article <6694@portia.Stanford.EDU> John Lynch writes:
>>I may have missed this discussion earlier, but I was wondering if anyone
>>knows what(if any) messages the Worskpace Manager sends to the running 
>>applications when the user hits the power off switch.  From the alert panel
>>that gets displayed and its statement that "all unsaved changes will be lost",
>>one would get the impression that all the Manager does is kill all of the
>>current processes.
>
>When the user tries to log out or power off the machine, the Workspace Manager
>sends a powerOffIn:andSave: method to all the apps started from the Workspace
>Manager itself.  The default implementation of this method in Application
>causes the appPowerOffIn:andSave: method to be called in the app's delegate
>with the same arguments sent from the Workspace Manager.  The first argument
>specifies the time remaining before the app will be killed, unless the app
>quits on its own accord earlier.  The second argument specifies if the user
>wants all files saved or not.  In 0.9, this argument would be YES or NO
>depending how the user replied to the "Cancel / Save / Don't Save" panel.
>In 1.0, this argument is always NO, indicating that the apps should not try 
>to save unsaved documents (hence the Workspace's warning, "all unsaved changes
>will be lost").

This seems to be less than optimal.  I do not always remember or know
if changes were made or need to be saved. I often hide a window or
application and could easily forget to save it.

Example:
I write a paper in WriteNow, hide it, open another, make changes.  If
I logout, the NeXT is not going to tell me I have unsaved changes.
Even if I remember to save the current window, I will probably forget
to save the hidden one.

Or what if someone wants to logout of my machine and log themselves
in.  they have no way of knowing what I have changed.

I like the Macintosh solution of going through each app and posting a
quit event.  It is much easier for the computer to prompt me for
changes rather than trying to remember where I made changes, going
there and saving them.  When I am tired, I make stupid mistakes,
please save me from them.

>>I've heard that in 0.8, there was more support for saving changes on
>>power off but that it was taken out for 0.9 and 1.0.  If this is true, does
>>anyone know the rationale for the change?
>
>Rather than having the user hit "Save" on the Logout panel and have all the 
>apps try to save their files within a finite time, it's better to have the
>user explicitly save the documents that need to be saved and not deal with
>the documents that don't need to be saved.  It might very well be the case
>that you don't want to save all the changes; only some of them.

When I quit, I should get the yes,no, cancel dialog for each window of
each app with changes.  I can save only the ones I want.

>And, as you can see from above, the apps do have time to clean up and tie
>loose ends; hitting "Logout" doesn't cause the Workspace to immediately
>blast away all the running apps. 

Apps have time to clean up, but all unsaved changes are lost.

>
>Ali

The problem with my solution is that is does not guarantee that the
machine will ever logout/powerdown.  I could leave a dialog up and not
respond to it and hang the logout.  I think this could be solved by
adding a button to the logout dialog.  So now it has three choices:

	Logout 	         - do not save changes (how it works now)
	Save if changes  - post a quit to each app and let it deal
	Cancel		 - Cancel shutdown

	Logout  	 - guarantees that the machine will shutdown
	Save  		 - no guarantee
	Cancel  	 - guaranteed not to shutdown.


This just seems a better way.  With the NeXT, I keep many applications 
open/hidden.  I am confident about the machine not bombing, so I am
less careful than I am on my Mac.  But I can just see having lots of
open unsaved windows/applications, and then logging out and losing it.

Why not just add the button?

Joe Liemandt
Stanford University