Add an append-to-body attribute for improved layering.

src/bootstrap/choices.tpl.html

@@ -1,6 +1,7 @@
 <ul class="ui-select-choices ui-select-choices-content dropdown-menu"
+    style="display: block"
     role="listbox"
-    ng-show="$select.items.length > 0">
+    ng-show="$select.open">
   <li class="ui-select-choices-group" id="ui-select-choices-{{ $select.generatedId }}" >
     <div class="divider" ng-show="$select.isGrouped && $index > 0"></div>
     <div ng-show="$select.isGrouped" class="ui-select-choices-group-label dropdown-header" ng-bind="$group.name"></div>

src/common.css

@@ -108,7 +108,7 @@
 }
 
 /* See Scrollable Menu with Bootstrap 3 http://stackoverflow.com/questions/19227496 */
-.ui-select-bootstrap > .ui-select-choices {
+.ui-select-choices {
   width: 100%;
   height: auto;
   max-height: 200px;
@@ -163,7 +163,7 @@
   border-right: 1px solid #428bca;
 }
 
-.ui-select-bootstrap .ui-select-choices-row>a {
+.ui-select-choices-row>a {
     display: block;
     padding: 3px 20px;
     clear: both;
@@ -173,21 +173,21 @@
     white-space: nowrap;
 }
 
-.ui-select-bootstrap .ui-select-choices-row>a:hover, .ui-select-bootstrap .ui-select-choices-row>a:focus {
+.ui-select-choices-row>a:hover, .ui-select-choices-row>a:focus {
     text-decoration: none;
     color: #262626;
     background-color: #f5f5f5;
 }
 
-.ui-select-bootstrap .ui-select-choices-row.active>a {
+.ui-select-choices-row.active>a {
     color: #fff;
     text-decoration: none;
     outline: 0;
     background-color: #428bca;
 }
 
-.ui-select-bootstrap .ui-select-choices-row.disabled>a,
-.ui-select-bootstrap .ui-select-choices-row.active.disabled>a {
+.ui-select-choices-row.disabled>a,
+.ui-select-choices-row.active.disabled>a {
     color: #777;
     cursor: not-allowed;
     background-color: #fff;

src/common.js

@@ -133,5 +133,25 @@ var uis = angular.module('ui.select', [])
   return function(matchItem, query) {
     return query && matchItem ? matchItem.replace(new RegExp(escapeRegexp(query), 'gi'), '<span class="ui-select-highlight">$&</span>') : matchItem;
   };
-});
+})
 
+/**
+ * A read-only equivalent of jQuery's offset function: http://api.jquery.com/offset/
+ *
+ * Taken from AngularUI Bootstrap Position:
+ * See https://github.com/angular-ui/bootstrap/blob/master/src/position/position.js#L70
+ */
+.factory('uisOffset',
+  ['$document', '$window',
+  function ($document, $window) {
+
+  return function(element) {
+    var boundingClientRect = element[0].getBoundingClientRect();
+    return {
+      width: boundingClientRect.width || element.prop('offsetWidth'),
+      height: boundingClientRect.height || element.prop('offsetHeight'),
+      top: boundingClientRect.top + ($window.pageYOffset || $document[0].documentElement.scrollTop),
+      left: boundingClientRect.left + ($window.pageXOffset || $document[0].documentElement.scrollLeft)
+    };
+  };
+}]);

src/select2/choices.tpl.html

@@ -1,4 +1,5 @@
-<ul class="ui-select-choices ui-select-choices-content select2-results">
+<ul class="ui-select-choices ui-select-choices-content select2-results"
+    ng-style="{top: position.top+'px', left: position.left+'px'}">
   <li class="ui-select-choices-group" ng-class="{'select2-result-with-children': $select.choiceGrouped($group) }">
     <div ng-show="$select.choiceGrouped($group)" class="ui-select-choices-group-label select2-result-label" ng-bind="$group.name"></div>
     <ul role="listbox"

src/selectize/choices.tpl.html

@@ -1,4 +1,5 @@
-<div ng-show="$select.open" class="ui-select-choices selectize-dropdown single">
+<div ng-show="$select.open" class="ui-select-choices selectize-dropdown single"
+     ng-style="{top: position.top+'px', left: position.left+'px'}">
   <div class="ui-select-choices-content selectize-dropdown-content">
     <div class="ui-select-choices-group optgroup" role="listbox">
       <div ng-show="$select.isGrouped" class="ui-select-choices-group-label optgroup-header" ng-bind="$group.name"></div>

src/uiSelectChoicesDirective.js

@@ -1,6 +1,6 @@
 uis.directive('uiSelectChoices',
-  ['uiSelectConfig', 'RepeatParser', 'uiSelectMinErr', '$compile',
-  function(uiSelectConfig, RepeatParser, uiSelectMinErr, $compile) {
+  ['uiSelectConfig', 'RepeatParser', 'uiSelectMinErr', 'uisOffset', '$compile', '$document',
+  function(uiSelectConfig, RepeatParser, uiSelectMinErr, uisOffset, $compile, $document) {
 
   return {
     restrict: 'EA',
@@ -21,6 +21,7 @@ uis.directive('uiSelectChoices',
 
         // var repeat = RepeatParser.parse(attrs.repeat);
         var groupByExp = attrs.groupBy;
+        var appendToBody = scope.$eval(attrs.appendToBody);
 
         $select.parseRepeatAttr(attrs.repeat, groupByExp); //Result ready at $select.parserResult
 
@@ -60,6 +61,44 @@ uis.directive('uiSelectChoices',
           var refreshDelay = scope.$eval(attrs.refreshDelay);
           $select.refreshDelay = refreshDelay !== undefined ? refreshDelay : uiSelectConfig.refreshDelay;
         });
+
+        if (appendToBody) {
+          scope.$watch('$select.open', function(isOpen) {
+            if (isOpen) {
+              positionDropdown();
+            } else {
+              resetDropdown();
+            }
+          });
+        }
+
+        // Hold on to a reference to the .ui-select-container element for appendToBody support
+        var parent = element.parent();
+
+        function positionDropdown() {
+          if (!appendToBody) {
+            return;
+          }
+
+          // Move the dropdown element to the end of the body
+          $document.find('body').append(element);
+
+          var position = uisOffset(parent);
+          element[0].style.left = position.left + 'px';
+          element[0].style.top = position.top + parent[0].offsetHeight + 'px';
+          element[0].style.width = parent[0].offsetWidth + 'px';
+        }
+
+        function resetDropdown() {
+          if (!appendToBody) {
+            return;
+          }
+          parent.append(element);
+          element[0].style.left = '';
+          element[0].style.top = '';
+          element[0].style.width = '';
+        }
+
       };
     }
   };