delete-event connected for disconnect from server

xsagtk/xsa_app_main.py

@@ -36,6 +36,11 @@ class XsaApp(gtk.Window):
         self.connect("destroy", gtk.main_quit)
         self.set_title("xsa")
 
+        def on_delete_event(*_):
+            import xsa.queries
+            xsa.queries.disconnect_xnat_server()
+
+        self.connect("delete-event", on_delete_event)
 
         vbox_root = gtk.VBox(False, 1)