diff --git a/src/ui/sand_box.c b/src/ui/sand_box.c
index d711b8f..14db78c 100644
--- a/src/ui/sand_box.c
+++ b/src/ui/sand_box.c
@@ -33,8 +33,8 @@ void on_activate_window_creation (GtkApplication *app, gpointer data)
 {
     GtkWidget *that_window = gtk_application_window_new (gtk_application_new ("org.gtk.test", 0));
     g_signal_connect (G_OBJECT (that_window), "destroy", G_CALLBACK(on_destroy), "exit(0) closes window\n");
-    gtk_window_set_title (GTK_WINDOW(that_window), "Gloups ! Who am I ?  Oooh...");
-    gtk_window_set_default_size (GTK_WINDOW(that_window), 300, 160);
+    gtk_window_set_title (GTK_WINDOW(that_window), "Ignition !");
+    gtk_window_set_default_size (GTK_WINDOW(that_window), 180, 140);
     GtkWidget *my_scrolling_thing = gtk_scrolled_window_new ();
     gtk_window_set_child (GTK_WINDOW (that_window), my_scrolling_thing);
     gtk_widget_show (that_window);
@@ -68,7 +68,7 @@ static void on_selection_change (GtkSelectionModel* my_selection_model,  guint p
         g_list_model_get_n_items (my_selection_model),
         g_list_model_get_item_type(my_selection_model),
         position,
-        gtk_string_object_get_string(g_list_model_get_item(my_selection_model, position)),
+        gtk_string_list_get_string (my_selection_model, position),
         n_items );
 }
 
@@ -81,6 +81,7 @@ GListModel *my_item_create_func (gpointer item, gpointer user_data)
 {
     printf("%s   ", gtk_string_object_get_string(item));
     gchar *my_child_array[] = {"1", "2", "3", NULL};
+
     if (gtk_string_object_get_string(item) == "zero") {
         GtkWidget *my_expander = gtk_expander_new (my_child_array);
         gtk_expander_set_child (my_expander, NULL);
@@ -93,9 +94,8 @@ GListModel *my_item_create_func (gpointer item, gpointer user_data)
 static void and_now_let_s_climb_that_tree (GtkWidget *in_that_box)
 {
     const gchar *my_array[] = {"zero", "one", "two", "three", "four", NULL};
-
     GtkStringList *my_string_list = gtk_string_list_new ((const char * const *) my_array);
-
+    gtk_string_list_append (my_string_list, "five");
     GtkMultiSelection *my_selection_model = gtk_multi_selection_new (G_LIST_MODEL (my_string_list));
 
     /* if (gtk_single_selection_get_selected_item (my_selection_model)) */
@@ -104,7 +104,7 @@ static void and_now_let_s_climb_that_tree (GtkWidget *in_that_box)
     GtkListItemFactory *my_list_item_factory = gtk_signal_list_item_factory_new ();
     g_signal_connect (my_list_item_factory, "setup", G_CALLBACK (on_setup_cb), NULL);
     g_signal_connect (my_list_item_factory, "bind", G_CALLBACK (on_bind_cb), NULL);
-    if (0) { g_signal_connect (my_selection_model, "selection-changed", G_CALLBACK (on_selection_change), NULL);}
+    if (1) { g_signal_connect (my_selection_model, "selection-changed", G_CALLBACK (on_selection_change), NULL);}
 
 
 //  GListModel *(* GtkTreeListModelCreateModelFunc) (GObject* item, gpointer user_data)  //  remplacerait gtk_string_list_new() ?
@@ -112,7 +112,8 @@ static void and_now_let_s_climb_that_tree (GtkWidget *in_that_box)
 //  https://docs.gtk.org/gtk4/method.TreeListRow.set_expanded.html
 
     GtkTreeListModel *my_tree_list_model = gtk_tree_list_model_new (my_selection_model, 1, 1, my_item_create_func, NULL, NULL);
-     printf("in : GListModel *item_create_func (gpointer item,...)   (line 80)\n");
+    int rank = 0; printf("in : GListModel *item_create_func (gpointer item,...)   (line 80)     (item n°%d is %s)\n",
+                      rank, gtk_string_list_get_string (my_string_list, rank));
 
     GtkWidget *my_list_view = gtk_list_view_new (GTK_SELECTION_MODEL (my_selection_model), my_list_item_factory);
 //    GtkWidget *my_tree_view = gtk_tree_view_new ();