Gtk::Notebook not showing

Question

I have a window with a vertical box layout. Within the layout, I've placed three widgets: a menu bar, a notebook and a status bar. The menu bar and the status bar work properly. But the notebook doesn't work as expected: no matter how many tabs I add, it will neither show anything nor append the tab (that is: _notebook->get_n_pages() is always 1).

The code for adding the tab:

Gtk::Label label;
Gtk::TreeView widget;
Gtk::TreeModelColumnRecord colrec;

// Columns are added here to 'colrec'

Glib::RefPtr<Gtk::ListStore> store = Gtk::ListStore::create(colrec);

widget.set_model(store);

_notebook->append_page(widget, label);

Am I missing something? The UI is loaded from a glade file. It is also displayed wrong within Glade because I've removed the default tabs.

Answer 1

I'm not 100% sure this is the culprit but for start your Gtk::TreeView gets destroyed. Try gtkmm manage/add vs smart pointers:.

#include <gtkmm.h>
#include <iostream>

void add(Gtk::Notebook& _notebook)
{
    Gtk::Label label;
    auto  widget = Gtk::manage(new Gtk::TreeView());
    Gtk::TreeModelColumnRecord colrec;

    // Columns are added here to 'colrec'

    Glib::RefPtr<Gtk::ListStore> store = Gtk::ListStore::create(colrec);

    widget->set_model(store);

    _notebook.append_page(*widget, label);
}

int main()
{
    auto Application = Gtk::Application::create();
    Gtk::Window window;

    Gtk::Notebook notebook;
    add(notebook);
    add(notebook);

    window.add(notebook);
    std::cout<<notebook.get_n_pages()<<std::endl;
    window.show_all();
    Application->run(window);
    return 0;
}