Re: Feed back on 1.0: Meaning of incremental attribute

Hi John,

> In Xforms 1.0, the description of the incremental attribute is inadequate.
>
> ... I think that it could be described though that
> incremental="true" means that each modification of the UI control by the
> user is committed to data.

My take on why it's currently vague is to specifically avoid saying
that the model is updated on each change. If a user types quickly then
you don't really want to change the data for each character, since if
you have this tied to a request for suggestion data over HTTP it can
get very slow. The same thing might happen with using a range to
resize images, etc., etc.

So the problem is that all you can really say is that specific
controls will have different strategies for when they commit the data
to the model, and that receipt of xforms-value-changed is an
indication that the model is up-to-date.

In formsPlayer controls we use a timer to see if the user has paused
for a certain amount of time, and then commit the data. Interestingly,
a lot of the Ajax libraries provide this kind of feature, although
obviously they use script rather than the attribute, and most allow
the delay to be set. (Some even allow the delay to be adjusted based
on things like network latency...but nothing in XForms prevents us
from doing the same thing.)

Regards,

Mark

-- 
Mark Birbeck
CEO
x-port.net Ltd.

e: Mark.Birbeck@x-port.net
t: +44 (0) 20 7689 9232
w: http://www.formsPlayer.com/
b: http://internet-apps.blogspot.com/

Download our XForms processor from
http://www.formsPlayer.com/

Received on Monday, 11 September 2006 10:44:02 UTC