[Usability] Decision: instant apply window buttons

[Seth Nickell <snickell stanford edu>]

This argument has been going around in circles so I think its time to
just make a decision.

DECISION: Instant apply windows should not have a dismissal button. They
may optionally have a Help button in the lower left corner of the
dialog.

RATIONALE:

The primary incentive for not having buttons on instant apply windows is
it makes the distinction between instant apply and non-instant apply
settings pages clear. It also is more accomodating of the general I-A
implied by instant apply property pages, and emphasizes their imodality.
This re-enforces a "good" conceptual model for users as it emphasizes
the direct manipulation aspect of instant apply windows. Rather than
asking the computer to make changes (i.e. a "dialog" with the computer)
users are conceptually put in direct control over properties.

There have been two primary objections to this approach:
  1) Users will be confused and not be sure how to dismiss the dialog
  2) Some window managers / themes will not have close buttons

1) I was concerned about this too and decided to conduct a small user
test to see if this was a problem. The basic conclusion of the test was
that users did not have serious problems with buttonless instant apply
windows. Most didn't even notice. See the "Usability Test" at the bottom
of this message for more detailed information on the user testing.

2) The "Window Manager" is responsible for managing windows. Should we
try to make GNOME accomodate broken window managers who have no resize
mechanism, or don't draw window borders correctly, by adding resize
handles inside GtkWindow? I would hope that everyone agrees we should
not. I think the situation with the close button is similar. Window
managers or themes that do not provide a mechanism for closing windows
are broken: they are not doing the job of managing windows adequately.
Furthermore, we need a standard keystroke for dismissing windows anyway,
which should work on instant apply windows too. I'm guessing that users
who use a window manager without a close button are primarily using
keystrokes anyway.

FUTURE DIRECTION:

It would be nice to have an API/Widget for property pages that handled
elements such as "Undo" and a nice placement for the "Help" button as
per auspex's proposal. We can work towards that, and perhaps prototype
it in control center as Havoc suggested.

-Seth



USABILITY TEST:

Participants:
  6 windows users, 1 CDE/windows user
  All seven subjects reported having little or no experience with MacOS
  (it was difficult to find any Unix users who did not also have
significant experience using MacOS)


Actual objective:
  Determine if instant apply "dialogs" without button cause problems for
users who are not experienced with them. The MacOS control panels were
chosen as the test material because they represent a fairly easy to use
instance of instant apply preferences.


Given objective:
  4 subjects were asked to change the background.
  3 subjects were asked to change the mouse speed.
  Subjects were asked to "think outloud".

Test observations:

5 out of 7 subjects did not find the control panels within a minute.
They were prompted and shown the control panel submenu under the apple
menu.

Once shown the control panel submenu, all 3 "mouse people" found the
mouse settings page without problems. 2 out of 4 "background people"
were prompted to go to "Appearance" after they had difficulty figuring
out which control panel the background was set from.

Once in the dialog, no "mouse people" and no "background people" had
difficulty accomlishing their objective.

Subjects were then instructed to "Run Microsoft Word"

3 subjects promptly closed the dialog using the "window manager" buttons
and went to find Microsoft Word. 

The other 4 subjects asked if they should close the dialog first. They
were told "Yes". 2 of these subjects proceded to close the dialog using
the "window manager" buttons. 

The 2 other subjects appeared to have difficulty closing the window. One
commented "there's no OK button on this". Both subjects did decide
within 10 seconds to close the window using the "window manager"
buttons, however both took a while to figure out which button was
"close". Both subjects felt unsure but eventually chose to click on the
correct button in the window titlebar.


Post session debriefing:

When prompted, two subjects (one of which also said "there's no OK
button on this" during the actual test) commented on lack of buttons in
the dialog. Neither had serious problems choosing to use the "window
manager" controls instead though. The other five said they hadn't really
noticed.

Both subjects who had difficulty closing the window mentioned that they
were looking for an "X" button.


Conclusion:

5 out of 7 users had no problems operating a buttonless instant apply
dialog. The other 2 users only experienced diffulty because they did not
recognize MacOS' close button. Although it took them longer both of
these users eventually guessed the right button.

My conclusion from this is that its not a learning problem, that people
pick up on it very quickly, and most people don't even notice.