bootstrap ui手风琴没有显示

Question

我不知道我做错了什么，但手风琴只是没有出现在我的视线上（只有一个矩形边框）。

这是代码：

<!-- Bootstrap Accordion -->
<div style="width:600px; margin:20px auto;">
<div ng-controller="AccordionCtrl">

<uib-accordion close-others="oneAtATime">
<uib-accordion-group heading="{{group.title}}" ngrepeat="group in groups">
{{group.content}}
</uib-accordion-group>
</uib-accordion>
</div>
</div>

这是控制器：

.controller('AccordionCtrl', function ($scope) {
// Add some content to accordion
$scope.groups = [
{
title: 'Header Content One',
content: 'Body Content One'
},
{
title: 'Header Content Two',
content: 'Body Content Two'
},
{
title: 'Header Content Three',
content: 'Body Content Three'
}
];
});