Is there a way to invoke an Angular $scope function from a different JavaScript file?

Question

Is there a way to invoke an Angular $scope function from a different JavaScript file?

I am currently troubleshooting a software application developed by someone else. The code uses Angular 1.5.9, which is not my area of expertise, and I've hit a roadblock in finding solutions to my queries.

I need to invoke a $scope function from a separate controller, located in a different JavaScript file.
When trying to use the broadcast statement below, I encounter an error message: "TypeError: Cannot read property '$broadcast' of null". I'm unsure about the cause of this error.

Here is the code:

CONTROLLER 1:

app.controller('FilterController', function ($scope, $filter, 
$uibModalInstance, errorService, dataService, values) {
    $scope.sortByColumn = function () {
      var data = { 'editorID': $scope.editorID(), 'filter': 
      dataService.data.objFilterColumns };

      dataService.getData('UpdateFilter', data).then(function (response) {
        $uibModalInstance.dismiss('cancel');

        //I WANT TO CALL THE SCOPE 'reloadData' FUNCTION HERE
        $scope.$emit('reloadData', data);

        //this broadcast statement was already there but it throws error 
        $scope.$parent.$broadcast('sortbyColumn', $scope.userFilters, $scope.column.strColumnName, $scope.orderDir, dataService.data.objFilterColumns);

    });
  });

CONTROLLER 2:

 app.controller("myCtrl", [
"$scope",
"$http",
"$uibModal",
"$log",
"$location",
"$window",
"dataService",
"errorService",
"lookupService"
, function ($scope, $http, $uibModal, $log, $location, $window, dataService, errorService, lookupService) {
    $scope.loadPage = function (data, message, removeFilter, byColumn, 
 orderDir) {
    //I want to call this function from the other controller 
  }

  $scope.$on("reloadData", function () {
     $scope.loadPage();
  });

  $scope.$on("sortbyColumn", function (event, filters, column, orderDir, filter) {
    //some code
  });
}]);

Appreciate your assistance with this matter.

javascript asp.net angularjs

Answer 1

Answer №1

Declare global JavaScript variables in your app.js file for each controller, for example:

var PayRateScope, ManageResourceScope, sequenceScopePA;

In your controller, at the end of the definition of the app.controller method, assign $scope to the respective global scope variable. For example:

// Payrare Controller
app.controller('PayRateAdminController', function ($scope, $compile, $http, $timeout) {
   // Your code and functions
  PayRateScope = $scope;
});

//ManageResource Contoller
app.controller('ManageResourceController', function ($scope, $compile, $http, $timeout) {
   // Your code and functions
  ManageResourceScope = $scope;
});

Now you can access functions inside the respective controller using its global variable in any external JavaScript file, like so:

PayRateScope.FunctionName();

Answer 2

Declare global JavaScript variables in your app.js file for each controller, for example:

var PayRateScope, ManageResourceScope, sequenceScopePA;

In your controller, at the end of the definition of the app.controller method, assign $scope to the respective global scope variable. For example:

// Payrare Controller
app.controller('PayRateAdminController', function ($scope, $compile, $http, $timeout) {
   // Your code and functions
  PayRateScope = $scope;
});

//ManageResource Contoller
app.controller('ManageResourceController', function ($scope, $compile, $http, $timeout) {
   // Your code and functions
  ManageResourceScope = $scope;
});

Now you can access functions inside the respective controller using its global variable in any external JavaScript file, like so:

PayRateScope.FunctionName();

Answer 3

Answer №2

One way to enhance your code base is by utilizing a service:

app.service('someService', function () {
    this.loadPage = function (data, message, removeFilter, byColumn, orderDir) {
        //...
    };
});

This service can then be injected into various controllers:

Controller1:

app.controller('FilterController',["$scope","someService" */andOther/*, function ($scope, someService) {
    $scope.sortByColumn = function () {
      var data = { 'editorID': $scope.editorID(), 'filter': 
      dataService.data.objFilterColumns };

      dataService.getData('UpdateFilter', data).then(function (response) {
        $uibModalInstance.dismiss('cancel');

       someService.loadPage(...parameters);


  });

Controller2:

 app.controller("myCtrl", ['$scope','someService' ,function($scope, someService){
    $scope.loadPage = someService.loadPage(data, message, removeFilter, byColumn, 
 orderDir);

}]);

In accordance with AngularJS docmentation:

AngularJS services are versatile objects that facilitate communication between different components via dependency injection (DI). By effectively using services, you can streamline and share code within your application.

Key characteristics of AngularJS services include:

Lazily instantiated – AngularJS waits to create a service until it's needed by a specific component. Singletons – Each component linked to a service accesses the same instance provided by the service factory.

Answer 4

One way to enhance your code base is by utilizing a service:

app.service('someService', function () {
    this.loadPage = function (data, message, removeFilter, byColumn, orderDir) {
        //...
    };
});

This service can then be injected into various controllers:

Controller1:

app.controller('FilterController',["$scope","someService" */andOther/*, function ($scope, someService) {
    $scope.sortByColumn = function () {
      var data = { 'editorID': $scope.editorID(), 'filter': 
      dataService.data.objFilterColumns };

      dataService.getData('UpdateFilter', data).then(function (response) {
        $uibModalInstance.dismiss('cancel');

       someService.loadPage(...parameters);


  });

Controller2:

 app.controller("myCtrl", ['$scope','someService' ,function($scope, someService){
    $scope.loadPage = someService.loadPage(data, message, removeFilter, byColumn, 
 orderDir);

}]);

In accordance with AngularJS docmentation:

AngularJS services are versatile objects that facilitate communication between different components via dependency injection (DI). By effectively using services, you can streamline and share code within your application.

Key characteristics of AngularJS services include:

Lazily instantiated – AngularJS waits to create a service until it's needed by a specific component. Singletons – Each component linked to a service accesses the same instance provided by the service factory.

Answer 5

Answer №3

To begin with, it is important to grasp the distinctions between $broadcast(), $emit() and $on()

$broadcast() - transmits an event downwards from a parent to child controllers.

$emit() - dispatches an event upwards from the current controller to all of its parent controllers

$on - An event triggered by $broadcast() and $emit() can be managed by setting up an event handler using $on()

$scope.$parent - implies accessing the parent controller's scope. This enables you to retrieve variables and methods in the parent controller.

It appears like this. https://i.sstatic.net/dBbbM.png Hopefully, this explanation clarifies these terms for you.

Answer 6

To begin with, it is important to grasp the distinctions between $broadcast(), $emit() and $on()

$broadcast() - transmits an event downwards from a parent to child controllers.

$emit() - dispatches an event upwards from the current controller to all of its parent controllers

$on - An event triggered by $broadcast() and $emit() can be managed by setting up an event handler using $on()

$scope.$parent - implies accessing the parent controller's scope. This enables you to retrieve variables and methods in the parent controller.

It appears like this. https://i.sstatic.net/dBbbM.png Hopefully, this explanation clarifies these terms for you.

Is there a way to invoke an Angular $scope function from a different JavaScript file?

Answer №1

Answer №2

Answer №3

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