[Usability] Unlock buttons

[Andy Owen <andy-gnome-usability ultra-premium com>]

I'm currently trying to improve the usability of the gnome-system-tools
package. Specifically, the way it interacts with PolicyKit with Unlock
buttons. The relevant bug reports are:

http://bugzilla.gnome.org/show_bug.cgi?id=578578
http://bugzilla.gnome.org/show_bug.cgi?id=558976

If you open the Users and Groups tool, you get a dialog like this:

http://www.ultra-premium.com/scratch/us1.png

(for those unfamiliar, when you click "Unlock" you will be given a
password prompt, and on getting the password right, all the things that
were insensitive become sensitive, and the "Unlock" button becomes
insensitive)

Clicking on "Manage Groups" shows this (modal) dialog:

http://www.ultra-premium.com/scratch/us2.png

This looked fairly bad to me, since the only way to do anything useful
here is to close this dialog, unlock the tool, and then go back. So I
wrote a patch which adds an unlock button:

http://www.ultra-premium.com/scratch/us3.png

It will probably find its way into the master branch soon, once I stop
sucking at writing patches :)

I'd like to do a similar thing for the user properties dialog. It has 3
tabs which look like this in their locked state:

http://www.ultra-premium.com/scratch/us4.png
http://www.ultra-premium.com/scratch/us5.png
http://www.ultra-premium.com/scratch/us6.png

I'm wanting to put an Unlock button on the left of the Cancel button. Is
it ok to do this, even though it doesn't apply at all to the first tab
("Account") - since nothing on that tab becomes sensitive as a result of
unlocking.


The next one:
http://www.ultra-premium.com/scratch/ss1.png

I'm thinking that making the checkboxes look disabled is the correct
solution, since it isn't expected that toggling a checkbox causes a
password dialog to pop up. Does this seem reasonable?

Finally, would it make sense to have a standard way of drawing a widget
that means "This widget will cause a password prompt to pop up if it is
activated"? So we could then get rid of Unlock buttons completely, but
also communicate to people what will happen when they activate a
control.

Feedback here, or in bug reports is appreciated.

Andy