Swaping layouts in GTK+3.

#include <gtk/gtk.h>

static void on_button1_clicked (GtkWidget * widget, gpointer user_data);
static void on_button2_clicked (GtkWidget * widget, gpointer user_data);
static void _quit (GtkWidget * widget, gpointer user_data);

GtkWidget * window;
GtkWidget * layout1;
GtkWidget * layout2;

main (int argc, char * argv[]) {
  gtk_init(&argc, &argv);
  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  layout1 = gtk_box_new (GTK_ORIENTATION_HORIZONTAL,3);
  layout2 = gtk_box_new (GTK_ORIENTATION_HORIZONTAL,3);

  GtkWidget * button1 = gtk_button_new_with_label ("Switch to Layout 2");
  GtkWidget * button2 = gtk_button_new_with_label ("Switch to Layout 1");

  GtkWidget * label1 = gtk_label_new ("Current layout: 1");
  GtkWidget * label2 = gtk_label_new ("Current layout: 2");

  gtk_container_add (GTK_CONTAINER (window), layout1);
  gtk_container_add (GTK_CONTAINER (layout1), label1);
  gtk_container_add (GTK_CONTAINER (layout1), button1);

  gtk_container_add (GTK_CONTAINER (layout2), button2);
  gtk_container_add (GTK_CONTAINER (layout2), label2);

  g_signal_connect (button1, "clicked", G_CALLBACK (on_button1_clicked), NULL);
  g_signal_connect (button2, "clicked", G_CALLBACK (on_button2_clicked), NULL);
  g_signal_connect (window, "destroy", G_CALLBACK (_quit), NULL);
  gtk_widget_show_all (window);

  gtk_main ();
  return 0;
}

static void on_button1_clicked (GtkWidget * widget, gpointer user_data) {
  g_print ("Bit\n");
  g_object_ref (G_OBJECT(layout1)); //prevents the layout from being destroyd.
  gtk_container_remove (GTK_CONTAINER (window), layout1);
  gtk_container_add (GTK_CONTAINER (window), (GtkWidget*) layout2);
  gtk_widget_show_all (window);
}


static void on_button2_clicked (GtkWidget * widget, gpointer user_data) {
  g_print ("Bup\n");
  g_object_ref (G_OBJECT(layout2)); //prevents the layout from being destroyd.
  gtk_container_remove (GTK_CONTAINER (window), layout2);
  gtk_container_add (GTK_CONTAINER (window), (GtkWidget*) layout1);
  gtk_widget_show_all (window);
}

static void _quit (GtkWidget * widget, gpointer user_data) {
  gtk_main_quit ();
}