将ng-class设置为true或false

我有一个Icon元素,我想根据其他东西切换类,

%i.fa.fa-bell{"ng-class" => "newActivities"}

我的控制器中有一个if/else语句,

var activities = $scope.activities

var init = function(){
  var hasValue = activities.some(function(obj) { return obj.viewed == "uncheck" });
  console.log (hasValue)

  if (hasValue == true){
    checked = true ;
    $scope.newActivities = 'newActivities';
  }
}

$scope.viewActivities = function (){
  angular.forEach(activities, function (activitie) {
    viewActivities.update({
      viewed: `check`,
      id:      activitie.id
    }).then(init);
  });
  $scope.newActivities = '';
}

现在发生的是当if值为true时,将其$scope.newActivities添加newActities到ng-class元素.但是,当语句不正确时,我无法弄清楚如何删除类.

好吧,你需要做的就是清理你的类变量,如下所示:

$scope.newActivities = '';

它将ng-class重新渲染class元素的属性.