// action = runnable or method name
static void onChangeAndNow(JComponent c, O r) {
  onUpdateAndNow(c, r);
}

static void onChangeAndNow(L<? extends JComponent> l, O r) {
  onUpdateAndNow(l, r);
}

static <A> JComboBox<A> onChangeAndNow(JComboBox<A> cb, IVF1<A> f) {
  onChange(cb, f);
  f?.get(getSelectItem_typed(cb));
  ret cb;
}