Migrating from GtkOptionMenu and GtkCombo to GtkComboBox and GtkComboBoxEntry

Migrating from GtkOptionMenu to GtkComboBox
Migrating from GtkCombo to GtkComboBoxEntry
New features

Prior to 2.4, GTK+ offered two widgets for the task of selecting one item from a list of options. GtkOptionMenu presents the list of options as a menu while GtkCombo presents them in a Windows-style list popup. The only difference between the two is that a GtkCombo allows to manually edit the selected value, while the GtkOptionMenu does not.

In GTK+ 2.4, a unified API for list selection was introduced, with GtkComboBox for the non-editable case and GtkComboBoxEntry for the editable case. The selection of the display style — menu or list — is no longer done at the API level, but has been made themeable via the style property "appears-as-list".

Migrating from GtkOptionMenu to GtkComboBox

Here is an example of a simple, but typical use of GtkOptionMenu:

GtkWidget *option_menu, *menu, *menu_item;

option_menu = gtk_option_menu_new ();      
menu = gtk_menu_new ();

menu_item = gtk_menu_item_new_with_label ("First Item");
gtk_menu_shell_append (GTK_MENU_SHELL (menu), menu_item);
gtk_widget_show (menu_item);
menu_item = gtk_menu_item_new_with_label ("Second Item");
gtk_menu_shell_append (GTK_MENU_SHELL (menu), menu_item);
gtk_widget_show (menu_item);
menu_item = gtk_menu_item_new_with_label ("Third Item");
gtk_menu_shell_append (GTK_MENU_SHELL (menu), menu_item);
gtk_widget_show (menu_item);

gtk_option_menu_set_menu (GTK_OPTION_MENU (option_menu), menu);

In order to react to the user's selection, connect to the "changed" signal on the option menu and use gtk_option_menu_get_history() to retrieve the index of the selected item.

And here is how it would be done with a GtkComboBox:

GtkWidget *combo_box;

combo_box = gtk_combo_box_text_new ();

gtk_combo_box_text_append (GTK_COMBO_BOX_TEXT (combo_box), "First Item");
gtk_combo_box_text_append (GTK_COMBO_BOX_TEXT (combo_box), "Second Item");
gtk_combo_box_text_append (GTK_COMBO_BOX_TEXT (combo_box), "Third Item");

In order to react to the user's selection, connect to the "changed" signal and use gtk_combo_box_get_active() to retrieve the index of the selected item.

A slightly more complex example involving images:

GtkWidget *option_menu, *menu, *menu_item;

option_menu = gtk_option_menu_new ();      
menu = gtk_menu_new ();

menu_item = gtk_image_menu_item_new_with_label ("First Item");
gtk_image_menu_item_set_image (gtk_image_new_from_pixbuf (pixbuf1));
gtk_menu_shell_append (GTK_MENU_SHELL (menu), menu_item);
gtk_widget_show (menu_item);
menu_item = gtk_image_menu_item_new_with_label ("Second Item");
gtk_image_menu_item_set_image (gtk_image_new_from_pixbuf (pixbuf2));
gtk_menu_shell_append (GTK_MENU_SHELL (menu), menu_item);
gtk_widget_show (menu_item);
menu_item = gtk_image_menu_item_new_with_label ("Third Item");
gtk_image_menu_item_set_image (gtk_image_new_from_pixbuf (pixbuf3));
gtk_menu_shell_append (GTK_MENU_SHELL (menu), menu_item);
gtk_widget_show (menu_item);

gtk_option_menu_set_menu (GTK_OPTION_MENU (option_menu), menu);

can be done using a GtkComboBox as follows:

GtkListStore *store;
GtkTreeIter iter;
GtkCellRenderer *renderer;
GtkWidget *combo_box;

store = gtk_list_store_new (2, GDK_TYPE_PIXBUF, G_TYPE_STRING);

gtk_list_store_append (store, &iter);
gtk_list_store_set (store, &iter, 0, pixbuf1, 1, "First Item", -1);
gtk_list_store_append (store, &iter);
gtk_list_store_set (store, &iter, 0, pixbuf2, 1, "Second Item", -1);
gtk_list_store_append (store, &iter);
gtk_list_store_set (store, &iter, 0, pixbuf3, 1, "Third Item", -1);

combo_box = gtk_combo_box_new_with_model (GTK_TREE_MODEL (store));

renderer = gtk_cell_renderer_pixbuf_new ();
gtk_cell_layout_pack_start (GTK_CELL_LAYOUT (combo_box), renderer, FALSE);
gtk_cell_layout_set_attributes (GTK_CELL_LAYOUT (combo_box), renderer,
                                "pixbuf", 0,
                                NULL);

renderer = gtk_cell_renderer_text_new ();
gtk_cell_layout_pack_start (GTK_CELL_LAYOUT (combo_box), renderer, TRUE);
gtk_cell_layout_set_attributes (GTK_CELL_LAYOUT (combo_box), renderer,
                                "text", 1,
                                NULL);