AngularJS: Sort on a multi select - angularjs

Question

I have a filter working on the multi select but when I try what I saw on the following link it doesn't work:
https://docs.angularjs.org/api/ng/filter/orderBy
How do I get the sort to change by clicking on the glyphicon?
<div>
<label>Available</label>
<label style="float: right; position: relative; left: 141px;">Assigned</label><br />
<input type="text" ng-model="filterText" style="width: 50px; position: relative; left:-36px;"/>
<button style="position: relative; left: -30px;">Filter</button>
<div style="position: relative; top: 0px; left: 311px; float: left;">
<span class="glyphicon glyphicon-sort-by-attributes-alt"></span>
<span class="glyphicon glyphicon-sort-by-attributes"></span>
</div>
<br />
<select id="available-groups" multiple>
<option value="{{group._id}}" ng-repeat="group in rbacGroups | filter:filterText">{{group.name}}</option>
</select>
<button id="addGroup" style="position: relative; top: -72px; left: 21px;">Add »</button><br />
<button id="removeGroup" style="position: relative; top: -72px; left: 375px;">« Remove</button>
<br />
<select id="assigned-groups" ng-model="cgroups" multiple required="required">
</select>
</div>

Answer 1

Change
ng-repeat="group in rbacGroups | filter:filterText"
to
ng-repeat="group in rbacGroups | filter:filterText | orderBy:'name':reverse"
and also change
<a href="" ng-click="reverse=!reverse;order('name', reverse)">...
<a href="" ng-click="reverse=!reverse;order('name', reverse)">...
to
<a href="" ng-click="reverse=false">...
<a href="" ng-click="reverse=true">...