angularjs - Add and remove class when element clicked with Angular -

i know how add or remove class html element when div clicked angularjs. have div when clicked need check if includes class('already-member') or not. if class exist, remove it, , if not, add it. know how in javascript not sure in angular.

tab-members.html

<div collection-repeat="friend in user.friends" item-width="50%" item-height="80px" class="friends-list">   <div class="item friend-avatar" ng-class="{'already-member' : friend.already_member == true}" ng-click="togglestatus()">     <div class="avatar">       <img src="{{friend.avatar_url}}">       <i class="check-icon" ng-class="{'hidden' : friend.already_member == false}"></i>     </div>     <div class="wrapper-friend-name">       <p class="friend-name">{{friend.name}}</p>     </div>   </div> </div> 

this code in controllers.js

.controller('membersctrl', function($scope) {   $scope.members = [     {avatar_url: "http://..."},     {avatar_url: "http://..."},     {avatar_url: "http://..."},     {avatar_url: "http://..."}   ];   $scope.user = {     avatar_url: "http://...",     friends: [       {avatar_url: "http://...", name: "pablo pepunto", already_member: true},       {avatar_url: "http://...", name: "pablo pepunto", already_member: false},       {avatar_url: "http://...", name: "pablo pepunto", already_member: false},       {avatar_url: "http://...", name: "pablo pepunto", already_member: false}     ]   }   $scope.$on('$ionicview.beforeenter', function (event, viewdata) {     viewdata.enableback = true;   });   $scope.togglestatus = function($scope) {     console.log('$scope'); //$scope undefined     $scope.classlist.toggle('already_member');     $scope.already_member = !$scope.already_member;    } }) 

i following:

in template:

ng-click="togglestatus(friend)" 

in controller:

$scope.togglestatus = function(friend) {     friend.already_member = !friend.already_member; } 

then ng-class="{'hidden' : friend.already_member == false}" directive defined should work.