help regarding gtk_window_default

[Deekshit Mantampady <dmantamp gmail com>]

Hi all,
  I have been trying to make a button on my WINDOW  a default one, so
that even if my foxus is on entry field, pressing ENTER should
activate the button. I have try the following peice of code. But it
didn't work. Please help me.

===============================================================

void default_button_clicked(GtkWidget *wid, gpointer d)
{
  printf("Default button clicked...\n");
}

void non_default_button_clicked(GtkWidget *wid, gpointer d)
{
  printf("NON-Default button clicked...\n");
}

int main(int argc, char *argv[])
{
  GtkWidget *window,  *vbox, *hbox, *btn, *entry;

  gtk_init(&argc, &argv);

  window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
  gtk_widget_set_size_request(window, 400,400);
  vbox = gtk_vbox_new(FALSE, 2);
  gtk_container_add(GTK_CONTAINER(window), vbox);
  gtk_widget_show(vbox);

hbox = gtk_hbox_new(FALSE, 2);
  gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, FALSE, 10);
  gtk_widget_show(hbox);

  entry = gtk_entry_new_with_max_length(10);
  gtk_box_pack_start(GTK_BOX(hbox), entry, TRUE, TRUE, 10);
  gtk_widget_show(entry);


  hbox = gtk_hbox_new(FALSE, 2);
  gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, FALSE, 10);
  gtk_widget_show(hbox);
  btn = gtk_button_new_with_label(" Non Default  ");
  gtk_signal_connect(GTK_OBJECT(btn), "clicked",
                     GTK_SIGNAL_FUNC(non_default_button_clicked), NULL);
  gtk_box_pack_start(GTK_BOX(hbox), btn, TRUE, FALSE, 10);
  gtk_widget_show(btn);

  hbox = gtk_hbox_new(FALSE, 2);
  gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, FALSE, 10);
  gtk_widget_show(hbox);
  btn = gtk_button_new_with_label(" Default");

  GTK_WIDGET_SET_FLAGS(btn, GTK_CAN_DEFAULT);
  gtk_window_set_default(GTK_WINDOW(window), btn);
  gtk_signal_connect(GTK_OBJECT(btn), "clicked",
                     GTK_SIGNAL_FUNC(default_button_clicked), NULL);
  gtk_box_pack_start(GTK_BOX(hbox), btn, TRUE, FALSE, 10);
  gtk_widget_show(btn);

  gtk_widget_show(window);
  gtk_main();

  return 0;
}
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