What I am trying to do is capture the button-press-event when a person
middle-clicks on a tab(similar to how Firefox tabs work).  As I learned
in #gtk+ using the EventBox should be able to do this
After a quick scouting of the web for an example, I found this:
http://www.async.com.br/faq/pygtk/index.py?req=show&file=faq17.003.htp

Unfortunately, I had problems with what I came up with.  By using the
following, when middle clicking on any of the tabs it finds the
page_num to be -1 ..
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#!/usr/local/bin/ruby --verbose
require 'gtk2'
include Gtk
init
win = Window.new
win.set_default_size 300, 300

hbox = HBox.new( false, 0)
win.add(hbox)

nb = Notebook.new
hbox.add(nb)

def add_page nb
    vbox = VBox.new( false, 0)
    tab_label_box = EventBox.new
    label = Label.new('test')
    tab_label_box.add(label)
    tab_label_box.show_all
    tab_label_box.signal_connect('button-press-event') do |widget,
event|
        if event.event_type==Gdk::Event::BUTTON_PRESS and
event.button==2
            puts nb.page_num(widget) # <-- not recognizing as a child ?
        end
    end
    nb.append_page( vbox, tab_label_box)
end

add_page nb
add_page nb
add_page nb

win.show_all
main
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