Hi,
I'm working on a multilingual site with SS. I have a problem creating a language chooser.
Therefore i looked inside the code from the widget (http://silverstripe.org/Language-Chooser-Widget-2/)
I changed some method invokation and so my Controller-code looks like:

  function LangChooser()
  {
      if (!isset(Controller::curr()->ID))
      {
          return; // So it doesn't break on Controller-less pages
      }
    $langs = Translatable::get_existing_content_languages();
    $data = new DataObjectSet();
    foreach (array_keys($langs) as $code)
    {
      if (i18n::get_lang_from_locale($code) == Translatable::current_lang())
      {
        $css_klasse = 'sel_lang';
      }
      else
      { 
        $css_klasse = '';
      }
         $page = Translatable::get_one_by_locale("SiteTree", $code, "`SiteTree`.ID = " . Controller::curr()->ID);

      if (!$page)
      {
        $data->push(new ArrayData(array('css_klasse' => $css_klasse, 'sprache' => i18n::get_lang_from_locale($code), 'link' => Director::protocolAndHost() . Director::baseURL() . '?locale=' . $code)));
      } else
      {
        $data->push(new ArrayData(array('css_klasse' => $css_klasse, 'sprache' => i18n::get_lang_from_locale($code), 'link' => Director::protocolAndHost() . Director::baseURL() . $page->URLSegment . '?locale=' . $code)));
      }
    }
    return $data;
  }

In my template I only need to do the following:

                <% control LangChooser %>
                  <% if Last %>
                    <a class="$css_klasse" href="$link"> $sprache </a>
                  <% else %>
                    <a class="$css_klasse" href="$link"> $sprache </a>&nbsp;/&nbsp; 
                  <% end_if %>
                <% end_control %>                

I used 'de_DE' as default-language.
Thats why my home page has 'home' as site name and the english version 'home-2'. If I now switch to english, the link back to german looks like:

http://mysite.localhost/home-2?locale=de_DE

This doesn't work, because 'home-2' stands for the english version and there is no german version for that.

Do I have to select the appropriate translation of the page from db to retrieving the right URL or is there a method that does the job for me?
Thank you,
roelfsche

I found the solution. For every language I retrieve the appropriate page from db and take the URLSegment.
Anyway, it looks like doing the job twice: first retrieving all translations and second retrieve the page for every translation for getting the right URLSegment.
Do I think right?
Thanks,
roelfsche

If you want to limit the language chooser to translations which actually exist for the current page, here's a recipe:
http://doc.silverstripe.org/doku.php?id=multilingualcontent#templates

Hello Ingo,
I've red that receipe but now I see, i didn't understood. Obviously the

hreflang="$Locale.RFC1766"