ionic publish and subscribe example

Here’s the scenario. I want to run an expensive function on a time interval that is called on many pages.
If someone else also calls the expensive function, it will ignore this request.

app.js

angular.module('app', [])
.run(['$ionicPlatform', '$rootScope',
 function($ionicPlatform, $rootScope) {

 $rootScope.startJob = true;
 $rootScope.$on('longjob', function (event, data) {
  if ($rootScope.startJob){
    $rootScope.startJob = false;
    setTimeout(function(){
      longFunction(data, function(e, result){
      //reset $rootScope
      $rootScope.startJob = true;
      });
    }, 2000);
  }
  });


 }]);

controller.js

function ctrl($scope){
    $scope.$emit('longjob', {});
}