Druid Validation

[Phil Muldoon <pmuldoon at redhat dot com>]

Hi all

We are experimenting with a Druid (or Wizard) that starts up, and
tailors your "session" to be more specific with the users needs (IE
interesting processes, processes that when they exit cause an action to
happen, and so on). We think this will help streamline the experience.

After a small amount of looking around, it seems that validation in a
Druid seems to be a non-standard gui concept. Eclipse - for example -
does hot validation on a multi-page Druid. So there are several
approaches. How should we do it? Here are several approaches I have seen
recently.

1) Hot Validation. The Next button is disabled (grayed) until all
information is correct and entered on that page. When correct
information is entered and completed, the Next button becomes enabled.
Edit any information to make it incorrect or incomplete, and the Next
button will move from an enabled state to a disabled state. Concerns
about this are: confusion regarding what information is correct if the
only prompt you receive is a disabled/enabled button. What does the
druid want?

2) Dialog based error/warnings. This time the Next (and Back) icons are
always enabled. If the user clicks Next and the information is
incomplete for that page, a dialog box will show explaining what they
are missing, and what is incorrect. The user clears the dialog and fixes
the information. Concerns here are 1) should the dialog box be modal as
not to get lost behind other windows if the user clicks out; 2) if the
box is modal, clearing the dialog box will remove the "what is wrong"
information. 

3) Finish based authentication. No validation is done until the user
clicks Finish. Then something like 2) will happen. I'm not a fan at all
of this approach.

Any thoughts here are welcome. 

Regards

Phil