[Zope] can zope and grok be a solution for a desktop like interractive web app

[Krishnakant]

hello all,
Seems my problem with reports is almost solved and I know that office
integration is also possible with zope.

Now my question is while I was reading grok tutorials, I realise that I
could not quite find some widgets which can do dynamic self updating or
database based validations.

For example if a user is making an invoice, the field holding entered
quantity must quickly query the db for the available current stock and
there has to be an error message which says "you don't have sufficient
stock for the given item ".

I don't see such widgets available in grok.  Am I missing some part?

I believe some ajax like functionality is needed here.

Further more, I will also need to develop drop down menus and such other
widgets.  I had discovered toscawidgets but get the impression that they
can be used on pylons and turbogears but not on zope?

Is this true?

happy hacking.
Krishnakant.