Re: Strange Gtk::TreeStore behaviour

["Marco Scholten" <mscholtn xs4all nl>]

> Hi,
>
> I am encountering an unexpected behavior in Gtk::TreeStore. I am
> connecting a handler to signal_row_expanded to refresh the row
> contents. To do this, I am simply removing the old contents and adding
> children again. But when I expand the row in GUI, it doesn't get
> expanded at all to show the children!

What's happening here is that the row is expanded before on_row_expanded is 
executed, you then remove the expanded children and add new ones, those new 
children don't get expanded again.

You can observe this behaviour by changing on_row_expanded to:

void ExampleWindow::on_row_expanded(const Gtk::TreeModel::iterator & iter, 
const Gtk::TreeModel::Path & path)
{
  std::cout << "on_row_expanded" << std::endl;
  while(Gtk::Main::events_pending()) Gtk::Main::iteration();
  char a;
  std::cin >> a;
  std::cout << "removing children" << std::endl;
  remove_children(*iter);
  std::cout << "adding children" << std::endl;
  add_children(*iter);
}

Fix it by connecting to signal_test_expand_row (this signal is emitted 
before the row is expanded) and then return false from your signal handler.

--
Marco