Angular: Empty Fiddle

http://angularjs.org/

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.6.1/angular.min.js"></script>
<div ng-controller="myCtrl1">
  <button ng-click="mapUsers1()">click</button>
  <div ng-controller="myCtrl2"></div>
</div>

JavaScript

var app = angular.module('myApp', []);

    app.controller('myCtrl2', function($scope, $rootScope) {

      $rootScope.$on("call_mapUsers_Method", function() {
        $scope.mapUsers();
      });

      $scope.mapUsers = function() {
        alert("done....");
      }
    });

    app.controller('myCtrl1', function($scope, $rootScope, $timeout) {
      $scope.mapUsers1 = function() {
        alert('test');
        $rootScope.$broadcast("call_mapUsers_Method", {});
      }

      $timeout(function() {
        $scope.mapUsers1();
      });
    });