Nested Links display

I was in the same situation. To save a bit of time, I copied the theme function code in better_exposed_filters.theme function theme_select_as_tree for counting depth

<?php
preg_match('/^(-*).*$/', $option_label, $matches);
$depth = strlen($matches[1]);
?>

And then wrapped a div tag around the link with a depth class

<?php
$link = '<div class="depth-'.$depth.'">'.l($value, bef_replace_query_string_arg($name, $key, $multiple));.'</div>';
?>

and then I can style the different depth levels that I need. Not a great solution, but it works.

Here's the whole thing to go into your template.php file:

<?php
function YOURTHEME_select_as_links($vars) {
  $element = $vars['element'];

  $output = '';
  $name = $element['#name'];

  // Collect selected values so we can properly style the links later
  $selected_options = array();
  if (empty($element['#value'])) {
    if (!empty($element['#default_values'])) {
      $selected_options[] = $element['#default_values'];
    }
  }
  else {
    $selected_options[] = $element['#value'];
  }

  // Add to the selected options specified by Views whatever options are in the
  // URL query string, but only for this filter
  $urllist = parse_url(request_uri());
  if (isset($urllist['query'])) {
    $query = array();
    parse_str(urldecode($urllist['query']), $query);
    foreach ($query as $key => $value) {
      if ($key != $name) {
        continue;
      }
      if (is_array($value)) {
        // This filter allows multiple selections, so put each one on the selected_options array
        foreach ($value as $option) {
          $selected_options[] = $option;
        }
      }
      else {
        $selected_options[] = $value;
      }
    }
  }

  $curr_depth = 0;
  $element['#options']['All'] = t('View All');
  // Go through each filter option and build the appropriate link or plain text
  foreach ($element['#options'] as $option => $elem) {
    
    // Check for Taxonomy-based filters
    if (is_object($elem)) {
      list($option, $elem) = each(array_slice($elem->option, 0, 1, TRUE));
    }

    /*
     * Check for optgroups.  Put subelements in the $element_set array and add a group heading.
     * Otherwise, just add the element to the set
     */
    $element_set = array();
    if (is_array($elem)) {
      $element_set = $elem;
    }
    else {
      $element_set[$option] = $elem;
    }

    $links = array();
    $multiple = !empty($element['#multiple']);
    
             
    $html = '';
    foreach ($element_set as $key => $value) {
      //dpm($value);
      preg_match('/^(-*).*$/', $value, $matches);
      $depth = strlen($matches[1]);
      //dpm($depth);

      
      // Custom ID for each link based on the <select>'s original ID
      $id = drupal_html_id($element['#id'] . '-' . $key);
      if (array_search($key, $selected_options) === FALSE) {
        $link = l(ltrim($value, '-'), bef_replace_query_string_arg($name, $key, $multiple));
        $html = '<div class="depth-'.$depth.'">'.$link.'</div>';
        $output .= theme('form_element', array('element' => array( '#id' => $id, '#children' => $html, '#markup' => '',
          '#name' => 'depth-'.$depth,)));
      } else {
        // Selected value is output without a link
        // TODO: add link to remove this option from the filter?
        $elem = array(
          '#id' => $id,
          '#children' => $value,
          '#markup' => '',
          '#name' => 'depth-'.$depth,
          );
        _form_set_class($elem, array('bef-select-as-links-selected'));
        $output .= theme('form_element', array('element' => $elem));
      }
    } // end foreach
    

  } // end foreach 



  $properties = array(
    '#description' => isset($element['#description']) ? $element['#description'] : '',
    '#children' => $output,
    '#name' => 'test-list',
  );

  return '<div class="bef-select-as-links">'
    . theme('form_element', array('element' => $properties))
    . '</div>';
}
?>

Daniel

Bit of an old threat, but here is my tweak for a real nested links list.

// removed

Edit: I removed the code from this post because of bugs. See post #5.

Capono, you rock! Thanks a lot for this solution, it's excellent.
I know it's easy to make suggestions, but maybe you could consider to contribute the code to the BEF or Views itself. Drupal needs this facility as an output plugin.
Cheers

Thanks. There were some bugs in post #3, so here is a better one. Put this code in your temple.php file in your theme folder and change the function name to your theme name.

function YOURTHEME_select_as_links($vars) {
  $element = $vars['element'];

  $output = '<ul class="bef-tree">';
  $curr_depth = 0;
  $name = $element['#name'];

  // Collect selected values so we can properly style the links later.
  $selected_options = array();
  $parents = array();
  if (empty($element['#value'])) {
    if (!empty($element['#default_values'])) {
      $selected_options[] = $element['#default_values'];
    }
  }
  else {
    $selected_options[] = $element['#value'];
    $parents[] = array_keys(taxonomy_get_parents($element['#value']));
  }

  // Add to the selected options specified by Views whatever options are in the
  // URL query string, but only for this filter.
  $urllist = parse_url(request_uri());
  if (isset($urllist['query'])) {
    $query = array();
    parse_str(urldecode($urllist['query']), $query);
    foreach ($query as $key => $value) {
      if ($key != $name) {
        continue;
      }
      if (is_array($value)) {
        // This filter allows multiple selections, so put each one on the
        // selected_options array.
        foreach ($value as $option) {
          $selected_options[] = $option;
        }
      }
      else {
        $selected_options[] = $value;
      }
    }
  }

  // Clean incoming values to prevent XSS attacks.
  if (is_array($element['#value'])) {
    foreach ($element['#value'] as $index => $item) {
      unset($element['#value'][$index]);
      $element['#value'][filter_xss($index)] = filter_xss($item);
    }
  }
  elseif (is_string($element['#value'])) {
    $element['#value'] = filter_xss($element['#value']);
  }

  // Go through each filter option and build the appropriate link or plain text.
  foreach ($element['#options'] as $option => $elem) {
    // Check for Taxonomy-based filters.
    if (is_object($elem)) {
      $slice = array_slice($elem->option, 0, 1, TRUE);
      list($option, $elem) = each($slice);
    }

    // Check for optgroups.  Put subelements in the $element_set array and add
    // a group heading. Otherwise, just add the element to the set.
    $element_set = array();
    if (is_array($elem)) {
      $element_set = $elem;
    }
    else {
      $element_set[$option] = $elem;
    }

    $links = array();
    $html = '';
    $multiple = !empty($element['#multiple']);

    // If we're in an exposed block, we'll get passed a path to use for the
    // Views results page.
    $path = '';
    if (!empty($element['#bef_path'])) {
      $path = $element['#bef_path'];
    }

    foreach ($element_set as $key => $value) {
      if (t('- Any -') == $value) {
        $depth = 0;
      }
      else {
        preg_match('/^(-*).*$/', $value, $matches);
        $depth = strlen($matches[1]);
        $value = ltrim($value, '-');
      }
      // Custom ID for each link based on the <select>'s original ID.
      $id = drupal_html_id($element['#id'] . '-' . $key);
      $elem = array(
        '#id' => $id,
        '#markup' => '',
        '#type' => 'bef-link',
        '#name' => $id,
      );

      $active = NULL;
      if (array_search($key, $selected_options) === FALSE) {
        $elem['#children'] = l($value, bef_replace_query_string_arg($name, $key, $multiple, FALSE, $path));
        $html .= theme('form_element', array('element' => $elem));
        $selected = '';
        if (in_array($key, $parents[0]) == TRUE) {
          $active = ' active';
        }
      }
      else {
        $elem['#children'] = l($value, bef_replace_query_string_arg($name, $key, $multiple, TRUE, $path));
        _form_set_class($elem, array('bef-select-as-links-selected'));
        $html .= str_replace('form-item', 'form-item selected', theme('form_element', array('element' => $elem)));
        $selected = ' selected';
        $active = NULL;
      }
    }

    if ($depth > $curr_depth) {
      // We've moved down a level: create a new nested <ul>.
      // TODO: Is there is a way to jump more than one level deeper at a time?
      // I don't think so...
      $output .= "<ul class='bef-tree-child bef-tree-depth-$depth". $selected ."'><li class='depth-". $depth ." item-". $key ."'>$html";
      $curr_depth = $depth;
    }
    elseif ($depth < $curr_depth) {
      // We've moved up a level: finish previous <ul> and <li> tags, once for
      // each level, since we can jump multiple levels up at a time.
      while ($depth < $curr_depth) {
        $output .= '</li></ul>';
        $curr_depth--;
      }
      $output .= "</li><li class='depth-". $depth ." item-". $key . $active . $selected ."'>$html";
    }
    else {
      // Remain at same level as previous entry. No </li> needed if we're at
      // the top level.
      if (0 == $curr_depth) {
        $output .= "<li class='depth-". $depth ." item-". $key . $active . $selected ."'>$html";
      }
      else {
        $output .= "</li><li class='depth-". $depth ." item-". $key ."'>$html";
      }
    }
  }

  if (!$curr_depth) {
    // Close last <li> tag.
    $output .= '</li>';
  }
  else {
    // Finish closing <ul> and <li> tags.
    while ($curr_depth) {
      $curr_depth--;
      $output .= '</li></ul></li>';
    }
  }

  // Close the opening <ul class="bef-tree"> tag.
  $output .= '</ul>';


  /*$properties = array(
    '#description' => isset($element['#bef_description']) ? $element['#bef_description'] : '',
    '#children' => $output,
  );*/

  $output .= '<div class="bef-select-as-links">';
  //$output .= theme('form_element', array('element' => $properties));
  if (!empty($element['#value'])) {
    if (is_array($element['#value'])) {
      foreach ($element['#value'] as $value) {
        $output .= '<input type="hidden" name="' . $name . '[]" value="' . $value . '" />';
      }
    }
    else {
      $output .= '<input type="hidden" name="' . $name . '" value="' . $element['#value'] . '" />';
    }
  }
  $output .= '</div>';

  return $output;
}

It sounds like folks have found a solution for this in the theme layer. If anyone can post a patch that turns this into a BEF option, I'd be happy to review and commit it. Until then, I'm going to mark this as closed. I've linked to this issue from the BEF docs so hopefully folks will find and continue to contribute to it.

Thank you to DanielWashbrook and capono for posting your solutions!

Thank you, I just need this option on a website I develop.
I didn't really understand the flow -
- I have put this code in my templete.php file and change the YOURTHEME to the name of my theme.
- Create a views page with 2 exposed fllters [Terms fields] that display in a block.

Yet I don't see any change in the html.

Go to admin/config/development/performance and delete the cache.