Index: elements.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/elements/elements.module,v
retrieving revision 1.1.2.2.2.9.2.2
diff -u -p -r1.1.2.2.2.9.2.2 elements.module
--- elements.module	12 Dec 2010 00:24:16 -0000	1.1.2.2.2.9.2.2
+++ elements.module	2 Feb 2011 18:26:42 -0000
@@ -51,6 +51,12 @@ function elements_element_info() {
     '#theme' => 'rangefield',
     '#theme_wrappers' => array('form_element'),
   );
+  $types['horizontal_tabs'] = array(
+    '#theme_wrappers' => array('horizontal_tabs'),
+    '#default_tab' => '',
+    '#pre_render' => array('form_pre_render_fieldset'),
+    '#process' => array('form_process_horizontal_tabs'),
+  );
 
   return $types;
 }
@@ -105,6 +111,10 @@ function elements_theme() {
       'render element' => 'element',
       'file' => 'elements.theme.inc',
     ),
+    'horizontal_tabs' => array(
+      'render element' => 'element',
+      'file' => 'elements.theme.inc',
+    ),
   );
 }
 
@@ -154,3 +164,30 @@ function form_process_placeholder($eleme
   }
   return $element;
 }
+
+/**
+ * Creates a group formatted as horizontal tabs.
+ *
+ * @param $element
+ *   An associative array containing the properties and children of the
+ *   fieldset.
+ * @param $form_state
+ *   The $form_state array for the form this vertical tab widget belongs to.
+ * @return
+ *   The processed element.
+ */
+function form_process_horizontal_tabs($element, &$form_state) {
+  // Inject a new fieldset as child, so that form_process_fieldset() processes
+  // this fieldset like any other fieldset.
+  $element['group'] = array(
+    '#type' => 'fieldset',
+    '#theme_wrappers' => array(),
+    '#parents' => $element['#parents'],
+  );
+
+  // Add JS and CSS necessary for the horizontal tabs
+  $element['#attached']['js'][] = drupal_get_path('module', 'elements') . '/js/horizontal_tab.js';
+  $element['#attached']['css'][] = drupal_get_path('module', 'elements') . '/css/horizontal_tab.css';
+
+  return $element;
+}
Index: elements.theme.inc
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/elements/Attic/elements.theme.inc,v
retrieving revision 1.1.4.2
diff -u -p -r1.1.4.2 elements.theme.inc
--- elements.theme.inc	11 Dec 2010 22:32:35 -0000	1.1.4.2
+++ elements.theme.inc	2 Feb 2011 18:26:42 -0000
@@ -142,3 +142,21 @@ function theme_rangefield($variables) {
 
   return $output;
 }
+
+/**
+ * Returns HTML for an element's children fieldsets as horizontal tabs.
+ *
+ * @param $variables
+ *   An associative array containing:
+ *   - element: An associative array containing the properties of the element.
+ *     Properties used: #children.
+ *
+ * @ingroup themeable
+ */
+function theme_horizontal_tabs($variables) {
+  $element = $variables['element'];
+
+  $output = '<h2 class="element-invisible">' . t('Horizontal Tabs') . '</h2>';
+  $output .= '<div class="horizontal-tabs-panes">' . $element['#children'] . '</div>';
+  return $output;
+}
Index: css/horizontal_tab.css
===================================================================
RCS file: css/horizontal_tab.css
diff -N css/horizontal_tab.css
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ css/horizontal_tab.css	2 Feb 2011 18:26:42 -0000
@@ -0,0 +1,54 @@
+/* $Id:$ */
+
+.horizontal-tabs-processed .horizontal-tabs-pane {
+  clear: both;
+  margin-top: 0;
+  padding: 0;
+}
+
+.horizontal-tabs-processed .horizontal-tabs-pane > legend {
+  display: none;
+}
+
+.horizontal-tabs .horizontal-tabs-list {
+  margin: 0;
+}
+
+.horizontal-tab-button {
+  list-style: none;
+}
+
+.horizontal-tab-button {
+  float: left; /* LTR */
+  margin-right: 4px; /* LTR */
+  position: relative;
+  top: 1px;
+  z-index: 0;
+}
+
+.horizontal-tab-button.last {
+  margin-right: 0;
+}
+
+.horizontal-tab-button a {
+  background: #efefef;
+  border: 1px solid #d5d5d5;
+  border-bottom-color: #ccc;
+  display: inline-block;
+  padding: 1px 5px 3px;
+  color: #000;
+}
+
+.horizontal-tab-button a:hover {
+  background: #d5d5d5;
+  text-decoration: none;
+}
+
+.horizontal-tab-button.selected a,
+.horizontal-tab-button.selected a:active {
+  background: #fff;
+  border: 1px solid #ccc;
+  border-bottom-color: #fff;
+  outline: none;
+  z-index: 1;
+}
Index: js/horizontal_tab.js
===================================================================
RCS file: js/horizontal_tab.js
diff -N js/horizontal_tab.js
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ js/horizontal_tab.js	2 Feb 2011 18:26:42 -0000
@@ -0,0 +1,156 @@
+// $Id:$
+
+(function ($) {
+
+/**
+ * Copy of the functionality of vertical tabs in Drupal 7 core
+ */
+Drupal.behaviors.horizontalTabs = {
+  attach: function (context) {
+    $('.horizontal-tabs-panes', context).once('horizontal-tabs', function () {
+      var focusID = $(':hidden.horizontal-tabs-active-tab', this).val();
+      var tab_focus;
+
+      // Check if there are some fieldsets that can be converted to horizontal-tabs
+      var $fieldsets = $('> fieldset', this);
+      if ($fieldsets.length == 0) {
+        return;
+      }
+
+      // Create the tab column.
+      var tab_list = $('<ul class="horizontal-tabs-list"></ul>');
+      $(this).wrap('<div class="horizontal-tabs clearfix"></div>').before(tab_list);
+
+      // Transform each fieldset into a tab.
+      $fieldsets.each(function () {
+        var horizontal_tab = new Drupal.horizontalTab({
+          title: $('> legend', this).text(),
+          fieldset: $(this)
+        });
+        tab_list.append(horizontal_tab.item);
+        $(this)
+          .removeClass('collapsible collapsed')
+          .addClass('horizontal-tabs-pane')
+          .data('horizontalTab', horizontal_tab);
+        if (this.id == focusID) {
+          tab_focus = $(this);
+        }
+      });
+
+      $('> li:first', tab_list).addClass('first');
+      $('> li:last', tab_list).addClass('last');
+
+      if (!tab_focus) {
+        // If the current URL has a fragment and one of the tabs contains an
+        // element that matches the URL fragment, activate that tab.
+        if (window.location.hash && $(window.location.hash, this).length) {
+          tab_focus = $(window.location.hash, this).closest('.horizontal-tabs-\n\
+\n\
+pane');
+        }
+        else {
+          tab_focus = $('> .horizontal-tabs-pane:first', this);
+        }
+      }
+      if (tab_focus.length) {
+        tab_focus.data('horizontalTab').focus();
+      }
+      
+      // Set a min width so the tabs won't float below
+      var minWidth = 0;
+      $('> li', tab_list).each(function () {
+        var outer = $(this).outerWidth(true);
+        minWidth = minWidth + outer;
+      });
+      $(this).parent().css('min-width', minWidth);
+
+    });
+  }
+};
+
+/**
+ * The horizontal tab object represents a single tab within a tab group.
+ *
+ * @param settings
+ *   An object with the following keys:
+ *   - title: The name of the tab.
+ *   - fieldset: The jQuery object of the fieldset that is the tab pane.
+ */
+Drupal.horizontalTab = function (settings) {
+  var self = this;
+  $.extend(this, settings, Drupal.theme('horizontalTab', settings));
+
+  this.link.click(function () {
+    self.focus();
+    return false;
+  });
+
+  // Keyboard events added:
+  // Pressing the Enter key will open the tab pane.
+  this.link.keydown(function(event) {
+    if (event.keyCode == 13) {
+      self.focus();
+      // Set focus on the first input field of the visible fieldset/tab pane.
+      $("fieldset.horizontal-tabs-pane :input:visible:enabled:first").focus();
+      return false;
+    }
+  });
+
+  // Pressing the Enter key lets you leave the tab again.
+  this.fieldset.keydown(function(event) {
+    // Enter key should not trigger inside <textarea> to allow for multi-line entries.
+    if (event.keyCode == 13 && event.target.nodeName != "TEXTAREA") {
+      // Set focus on the selected tab button again.
+      $(".horizontal-tab-button.selected a").focus();
+      return false;
+    }
+  });
+};
+
+Drupal.horizontalTab.prototype = {
+  /**
+   * Displays the tab's content pane.
+   */
+  focus: function () {
+    this.fieldset
+      .siblings('fieldset.horizontal-tabs-pane')
+        .each(function () {
+          var tab = $(this).data('horizontalTab');
+          tab.fieldset.hide();
+          tab.item.removeClass('selected');
+        })
+      .end()
+      .show()
+      .siblings(':hidden.horizontal-tabs-active-tab')
+      .val(this.fieldset.attr('id'));
+
+    this.item.addClass('selected');
+    // Mark the active tab for screen readers.
+    $('#active-horizontal-tab').remove();
+    this.link.append('<span id="active-horizontal-tab" class="element-invisible">' + Drupal.t('(active tab)') + '</span>');
+    $(this.fieldset).trigger('horizontalTabActivate', this);
+  }
+};
+
+/**
+ * Theme function for a horizontal tab.
+ *
+ * @param settings
+ *   An object with the following keys:
+ *   - title: The name of the tab.
+ * @return
+ *   This function has to return an object with at least these keys:
+ *   - item: The root tab jQuery element
+ *   - link: The anchor tag that acts as the clickable area of the tab
+ *       (jQuery version)
+ */
+Drupal.theme.prototype.horizontalTab = function (settings) {
+  var tab = {};
+  tab.item = $('<li class="horizontal-tab-button" tabindex="-1"></li>')
+    .append(tab.link = $('<a href="#"></a>')
+    .append(tab.title = $('<span></span>').text(settings.title))
+  );
+  return tab;
+};
+
+})(jQuery);