signal_*_event and tab labels of Notebook

[Jakub Okoński <jakub okonski org>]

I'm trying to implement closing the tab of a Notebook by middle mouse button and I want to do that by creating a label and connecting to signal_press_button_event().

I have a class which loads contents from files and outputs it to TextView. There's a `Gtk::Label representational_` which is used for tab head.

Functionality for set_file(Gio::File) in that class involves this code:

  // create representational widget if there's not

  if (!representational_) {

    auto new_rep = std::make_shared<Gtk::Label>();

    std::swap(representational_, new_rep);

  }

  // assign text

  representational_->set_text(file_->get_basename());

  auto window = representational_->property_window().get_value();

  if (window) {

    window->set_events(window->get_events() | Gdk::EventMask::BUTTON_PRESS_MASK);

    //representational_->property_selectable().set_value(true);

    representational_->property_sensitive().set_value(true);

    representational_->property_can_focus().set_value(true);

    representational_->add_events(Gdk::BUTTON_PRESS_MASK);

    representational_->signal_button_press_event().connect(sigc::ptr_fun(&the_event), false);

  }

The way I use this class is to create it, set_file to it (notebook page does not exist yet, so window is a null pointer), then I Gtk::Notebook::append_page() using the representational_, and set_file() again (window exists this time).

But it works only if I uncomment the line which assigns selectable property to true. I've looked at the Gtk+ code and I know it ensures that Gdk::Window is created.

Obviously, selecting text in that label is unacceptable for me, but I need to trigger the Gtk::Widget::realize() method somehow.