def on_file_quit_activate(self, menuitem): if self.current_iter is not None: chunk = self.current_view.save_chunk() if chunk: self.store.set_value(self.current_iter, 1, chunk) chunks = [] self.store.foreach(lambda model, path, iter: chunks.append(model.get_value(iter, 1))) Png(chunks).write(file("test.png", "wb")) gtk.main_quit()