[gtkmm] Passing a pointer to a class using D&D

["Miller, Ryan D" <MilleRD kscems ksc nasa gov>]

Greetings everyone,

Another question for the great readers of gtkmm list.  I need to access
several fields of information from a class after a user performs a drag
from that class onto another one.  (Both classes are derived from
EventBoxes).  I figured out how to pass a single value, such as a
string, based on the examples by casting the string into a guchar* and
then using get_data_as_string on the receiving end.  In order to pass
more than one thing, I was hoping to pass the address of the passing and
then create a pointer to the passing class on the receiving end and use
that to access what I need.  Is this a feasible way to do this?  In a
more concise manner: I would like to pass a pointer to "this" using D&D.
The code I have right now is below, but I end up with different values
for the addresses on both ends.  Does anyone know how to do this?

In drag_data_get(..) in my passing class:

  Selection_data.set( selection_data.get_target(), 8, (const guint8
*)this, sizeof(this));

In drag_data_received(..) in my receiving class (templateBoxTarget):

  templateBoxTarget *t = (templateBoxTarget *)
selection_data.get_data();

And I have also tried something like this as a shot in the dark, but got
the same results:
  void *pVoid = (void *)selection_data.get_data();
  templateBoxTarget *t = static_cast<templateBoxTarget *> (pVoid);

Thanks!,
Ryan