+/* Creates widgets to show in a progress dialog, may set up state via user_data */
+typedef void (*VikDataSourceAddProgressWidgetsFunc) ( GtkWidget *dialog, gpointer user_data );
+
+/* Frees any widgets created for the setup or progress dialogs, any allocated state, etc. */
+typedef void (*VikDataSourceCleanupFunc) ( gpointer user_data );
+
+
+struct _VikDataSourceInterface {
+ const gchar *window_title;