[platform-dev] Data exchange controller <=> dialog ?

[artisan]

What's the intended way to exchange data between a controller and a
dialog ? It's probably a very naïve question ... sorry for that. :-)

The generated comments in the dialog class' store() and load() suggests
to use Preferences or NbPreferences for that. In my case however this
doesn't work:

* NbPreferences works with elementary data types only (int, String,
boolean,...). I'm using a custom class because the dialog is a bit more
complicated than a few text fields.

* NbPreferences are obtained based on a class. Unfortunately I've got
different instances of the same dialog class running at the same time.

Is there an api to exchange specific instances of custom classes
between controller and dialog ? Or should this be developed especially
case per case ?

Many thanks for helping !

Jan