ifclass JExtendedTabbedPane
  svoid onTabSelectedAndNow(JExtendedTabbedPane tabs, Runnable r) {
    if (tabs != null)
      onTabSelectedAndNow(tabs.tabs, r);
  }
endif

svoid onTabSelectedAndNow(JTabbedPane tabs, Runnable r) {
  if (tabs != null && r != null) swing {
    onTabSelected(tabs, r);
    r.run();
  }
}

svoid onTabSelectedAndNow(JTabbedPane tabs, IVF1<Int> r) {
  if (tabs != null && r != null) swing {
    onTabSelected(tabs, r);
    r.get(tabs.getSelectedIndex());
  }
}

Began life as a copy of #1020865