billy-gtk4-interface/main.cpp

#include "hello_world.hpp"
#include <gtkmm/application.h>
#include <gtkmm/builder.h>
#include <iostream>
#include <memory>

int main(int argc, char *argv[]) {
    auto app = Gtk::Application::create("org.gtkmm.example");

    const auto menu_model = []() -> Glib::RefPtr<Gio::Menu> {
        try {
            const auto builder = Gtk::Builder::create_from_file("menu_bar.ui");
            return std::dynamic_pointer_cast<Gio::Menu>(builder->get_object("menu"));
        } catch (const std::exception &e) {
            std::cerr << e.what() << '\n';
            return nullptr;
        }
    }();
    if (menu_model == nullptr) {
        std::cerr << "Menu model object is null. Down-cast failed.\n";
        return EXIT_FAILURE;
    }
    return app->make_window_and_run<learn_gtkmm4::HelloWorld>(argc, argv, menu_model);
}