Gtk-CRITICAL **: _gtk_builder_extend_with_template: assertion 'buffer && buffer[0]' failed

[songqing shan <shans123 hotmail com>]

Hello,


I would like to have someone help me with following situation.

I wrote a few custom widgets such as bao_model, and bao_model_container with ui files. These widgets work 
well in some environments such as



static void project_setup(GSimpleAction *action, GVariant *parameter, gpointer window)
{
     GtkWidget *test;

 test= bao_model_container_new ();
 test = bao_model_new ();
 test = bao_assistant_new ();
}


However, when I use these custom widgets with gtkdialog, following error occurs

Gtk-CRITICAL **: _gtk_builder_extend_with_template: assertion 'buffer && buffer[0]' failed.  My code is as 
follows.


static void project_setup(GSimpleAction *action, GVariant *parameter, gpointer window)
{
      GtkWidget *test;

     BaoAppProject *dialog;

     BaoAppWindowPrivate *priv;
     priv = bao_app_window_get_instance_private(window);

 dialog = bao_app_project_new(BAO_APP_WINDOW(window));
 gtk_window_present(GTK_WINDOW(dialog));

 /*the program is waiting for the "response" signal*/
 gint response_id = gtk_dialog_run(GTK_DIALOG(dialog));

 switch(response_id)
 {
  case GTK_RESPONSE_APPLY:
         //test= bao_model_container_new ();
        test = bao_model_new ();
         //test = bao_assistant_new ();

      //  test = gtk_label_new("my test"); // works
         break;

   default:
        g_print("default Id: %d \n", response_id);
         break;
 }

}


All custom widgets have the same error when they are run separately or together. When I use other gtkwidget 
such as gtklabel, they are fine. I do not know why the error occurs and how to revise them.  Any comments and 
suggests will be appreciated.


Thanks,


Song