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Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!lll-lcc!unisoft!hoptoad!gnu
From: gnu@hoptoad.uucp (John Gilmore)
Newsgroups: comp.sys.mac,comp.sys.mac.programmer
Subject: Re: List Items Handling...
Message-ID: <6001@hoptoad.uucp>
Date: 6 Dec 88 07:40:16 GMT
References: <7743@orstcs.CS.ORST.EDU> <6000@hoptoad.uucp>
Organization: Grasshopper Group in San Francisco
Lines: 33

tim@hoptoad.uucp (Tim Maroney) wrote (talking about dimmed menu items):
> There are a few different ways to deal with the selection issue.  The
> best way is probably never to allow a disabled cell to be selected.

I find this one of the worst aspects of the Mac user interface.
I can see that you might want to keep things in the list, even though
they can't be done right now, so that the size and position of the
following items will not change all the time.  But this way of handling
selection makes it hard or impossible for the user to do things that
are easy in a traditional command-based user interface.

In most cases when I want to deal with a dimmed item, I want to select
it to get something done (e.g. read in a new file) but there is
something I have to do first before it will let me do it (e.g. write
out the one I already have).  In a command based interface I would
command it to read in the new file and would get an error message, e.g.
"Can't read a new file until you save or dispose of the old one".  In a
dimmed-menu interface where you can't select the dimmed items, there is
no way to find out what it wants me to do before it will "let me"
command it to take the action I want done.

The solution is simple; you let dimmed items be selected, and if one
is selected, you print an error message (display an alert, whatever the
Mac calls it) that says what the problem is.  Write these messages
from the point of view that you are a human who desperately wants
to make the computer do the thing that they selected, e.g. they
picked this menu item for a reason!  Tell them what they need to know
about how to do it; don't tell them "you selected a dimmed menu item idiot",
tell them "you can't load a file because first you need to quit out of
the one you are in -- use the Quit or Save or Save As menu item".
-- 
John Gilmore    {sun,pacbell,uunet,pyramid,amdahl}!hoptoad!gnu    gnu@toad.com
		"The network *is* the confuser."