GtkTreeModel *model;
GtkTreeIter iter;
int mode_id;
gboolean iter_ok;
model = gtk_combo_box_get_model (combobox);
gtk_combo_box_get_active_iter (combobox, &iter);
iter_ok = gtk_combo_box_get_active_iter (combobox, &iter);
if(!iter_ok) return;
gtk_tree_model_get (model, &iter,
COL_MODE_ID, &mode_id,
-1);