I found a small mistake in your example on the page
http://www.gtkmm.org/docs/gtkmm-2.4/docs/tutorial/html/ch15s06.html

bool myarea::on_expose_event(GdkEventExpose* ev)
{
Glib::RefPtr<Gdk::PixBuf> image =
Gdk::PixBuf::create_from_file("myimage.png");
image->render_to_drawable(get_window(),
get_style()->get_black_gc(),
0, 0, 100, 80, image->get_width(),
image->get_height(), // draw the whole image (from 0,0
to the full width,height) at 100,80 in the window
Gdk::RGB_DITHER_NONE, 0, 0);
return true;
}

The name of the class is Pixbuf not PixBuf. Being used
to CamelCaps, it took mea while to figure out what
went wrong ;-)