Copying widgets

[Jim George <jimgeorge gmail com>]

Hi all,
I'm writing a program that, like gimp, has a control window, from
which users can open one or more viewer windows that present different
aspects of a data set (it's a weather radar display program). The
sub-windows are identical, and I'm using libglade and glade-3 to do
the interface layouts. Currently, I call glade_xml_new each time I
want to create a new window. Is there a better way, which prevents
libglade from having to parse the XML each time?

Also, I'm interested in moving to GtkBuilder. Do I use different xml
files for each window and create a new GtkBuilder object for each new
viewer window, or is there a smarter way?
Thanks in advance.
-Jim