button_open->signal_clicked().connect(sigc::ptr_fun(studio::App::dialog_open));
button_save->signal_clicked().connect(sigc::ptr_fun(save_selected_instance));
button_saveas->signal_clicked().connect(sigc::ptr_fun(save_as_selected_instance));
button_open->signal_clicked().connect(sigc::ptr_fun(studio::App::dialog_open));
button_save->signal_clicked().connect(sigc::ptr_fun(save_selected_instance));
button_saveas->signal_clicked().connect(sigc::ptr_fun(save_as_selected_instance));