How to dynamically generate XPS pages / subclass DocumentPaginator

Hi all,

I would like to use DocumentViewer Control to display XPS like documents. As
my documents may contain several thousands of pages it is not feasible to
generate them all in advance. I need a way to create pages on the fly when
they appear in the control.

For retrieving pages from the document there exists the DocumentPaginator
class. For my purposes I would need my own implementation of this class that
overrides the GetPage() and GetPageAsync() methods and implement it in a way
that a requested page is generated on the fly. This class is abstract so
custom implementations should be possible.

But my problem is: How can I make my FixedDocument aware of my derived
DocumentPaginator? FixedDocument has the DocumentPaginator property but no
setter method.

My workaround was to derive my own class from FixedDocument containing my
paginator and to override the getter of the DocumentPaginator property. But
this does not work. The control just remains empty (strange enough I would
not FixedDocument at all, just the paginator would be sufficient, but then
DocumentViewer control complains that it only supports FixedDocument and
FlowDocument types...)

Dynamic generation of pages should not be such an exotic requirement. Did I
miss something?

Thanks for any help

Jens