Auto trigger function throuigh service in angularjs - angularjs

hi all i am using angulrajs passing one value from one controller to another controller using service it's work fine but my need is when service value change in controller 2 i get the service value in one scope when scope value change i need trigger the function it's called refresh function when service value change and that i need to call the refresh function here my fiddle
https://jsfiddle.net/ctawL4t3/10/

You can just $watch your value.storeObject. Though it's not best of the practices, but it suits this kind of feature.
$scope.$watch('value.storedObject', function(newVal) {
if(newVal !== '') {
refresh()
}
})
working fiddle (open console to see refresh function logging)

You can try to use angular default $emit, $broadcast, or try to do 2 simple functions in own service
angular.module('app').factory('StoreService', function() {
var listeners = {};
var emit = function(name, val) {
if(listeners[name]) {
listeners[name](val)
}
}
var on = function(name, callback) {
listeners[name] = callback;
}
return {
emit: emit,
on: on,
storedObject: ''
};
});
JSFiddle example
JSFiddle example $watch
JSFiddle example ng-change is better because, you can use easily debounce

you can use broadcast function for that
Please check this SO link to find the related answer
How to call a function from another controller in angularjs?
app.controller('One', ['$scope', '$rootScope'
function($scope) {
$rootScope.$on("CallParentMethod", function(){
$scope.parentmethod();
});
$scope.parentmethod = function() {
// task
}
}
]);
app.controller('two', ['$scope', '$rootScope'
function($scope) {
$scope.childmethod = function() {
$rootScope.$emit("CallParentMethod", {});
}
}
]);

Related

Call controller function from service in angularjs

I am using socket.io to enable chat in my app and i am using a service SocketService to perform all the socket stuff. When a message came then i want to trigger a function of a controller from the service SocketService to make some changes in the UI.
So i want to know that how can i access the function of a controller from the service.
Sample Code:
.service('SocketService', function ($http,$rootScope,$q) {
this.connect = function(){
var socket = io();
socket.on('connect',function(){
// Call a function named 'someFunction' in controller 'ChatController'
});
}
});
This is the sample code for service.
Now the code for controller
.controller('ChatController',function('SocketService',$scope){
$scope.someFunction = function(){
// Some Code Here
}
});
You could achieve this by using angular events $broadcast or $emit.
In your case $broadcast would be helpful,
You need to broadcast your event in $rootscope that can be listen by all the child scopes which has $on with same event name.
CODE
.service('SocketService', function($http, $rootScope, $q) {
this.connect = function() {
var socket = io();
socket.on('connect', function() {
// Call a function named 'someFunction' in controller 'ChatController'
$rootScope.$broadcast('eventFired', {
data: 'something'
});
});
}
});
.controller('ChatController', function('SocketService', $scope) {
$scope.someFunction = function() {
// Some Code Here
}
$scope.$on('eventFired', function(event, data) {
$scope.someFunction();
})
});
Hope this could help you, Thanks.
I know this is an old question, but I have another option. I have a personal bias against $broadcast - it just doesn't feel very 'angularish', I prefer making explicit calls in my code.
So instead of broadcasting to the controller and triggering another digest cycle, I prefer to have the controller register itself to the service, as below. Just be careful not to introduce any circular dependencies if the controller makes use of the same service. This works best with the controllerAs syntax, so that the calling service does not need to care about $scope.
Yes, this is more code than $broadcast, but it does give the service total access to the entire controller - all of it's methods and properties.
.service('SocketService', function ($http,$rootScope,$q) {
var _this = this;
this.chatController = null;
this.registerCtrlr = function (ctrlr) {
_this.chatController = ctrlr;
};
this.unRegisterCtrlr = function () {
_this.chatController = null;
};
this.connect = function(){
var socket = io();
socket.on('connect',function(){
// Call chatController.someFunction if chatController exists
if (_this.chatController) {
_this.chatController.someFunction();
}
});
};
});
.controller('ChatController',['SocketService', '$scope', function(SocketService, $scope){
SocketService.registerCtrlr(this);
//-- make sure controller unregisters itself when destroyed - need $scope for this
$scope.$on('$destroy', function () {
SocketService.unRegisterCtrlr();
});
this.someFunction = function(){
// Some Code Here
}
}]);
I realize this post is old but I'd like to give my two cents after dealing with Angular JS for several years. I personally would reconsider this approach. Ideally with AngularJS you'd modify your controller/directive to facilitate transferring data to the view model and ultimately bind an HTML template to what I call "the user friendly" view model. This view model should simply reflect what you want the user to see and when in general. Using this method the moment connect event happens your view model which should be bound to the service's data will reflect changes to the data the moment the data arrives.

Can not figure out how to store $rootScope in angular.bootstrap

I'm trying to call a web service in AngularJS bootstrap method such that when my controller is finally executed, it has the necessary information to bring up the correct page. The problem with the code below is that of course $rootScope is not defined in my $http.post(..).then(...
My response is coming back with the data I want and the MultiHome Controller would work if $rootScope were set at the point. How can I access $rootScope in my angular document ready method or is there a better way to do this?
angular.module('baseApp')
.controller('MultihomeController', MultihomeController);
function MultihomeController($state, $rootScope) {
if ($rootScope.codeCampType === 'svcc') {
$state.transitionTo('svcc.home');
} else if ($rootScope.codeCampType === 'conf') {
$state.transitionTo('conf.home');
} else if ($rootScope.codeCampType === 'angu') {
$state.transitionTo('angu.home');
}
}
MultihomeController.$inject = ['$state', '$rootScope'];
angular.element(document).ready(function () {
var initInjector = angular.injector(["ng"]);
var $http = initInjector.get("$http");
$http.post('/rpc/Account/IsLoggedIn').then(function (response) {
$rootScope.codeCampType = response.data
angular.bootstrap(document, ['baseApp']);
}, function (errorResponse) {
// Handle error case
});
});
$scope (and $rootScope for that matter) is suppose to act as the glue between your controllers and views. I wouldn't use it to store application type information such as user, identity or security. For that I'd use the constant method or a factory (if you need to encapsulate more logic).
Example using constant:
var app = angular.module('myApp',[]);
app.controller('MainCtrl', ['$scope','user',
function ($scope, user) {
$scope.user = user;
}]);
angular.element(document).ready(function () {
var user = {};
user.codeCampType = "svcc";
app.constant('user', user);
angular.bootstrap(document, ['myApp']);
});
Note Because we're bootstrapping the app, you'll need to get rid of the ng-app directive on your view.
Here's a working fiddle
You could set it in a run() block that will get executed during bootstrapping:
baseApp.run(function($rootScope) {
$rootScope.codeCampType = response.data;
});
angular.bootstrap(document, ['baseApp']);
I don't think you can use the injector because the scope isn't created before bootstrapping. A config() block might work as well that would let you inject the data where you needed it.

Getting button to fire using Controller as vm syntax in AngularJS 1.3

I've got the code below that shows that I can use $scope.interestToggle = syntax but not vm.interestToggle = syntax to assign a listener to a button click. I'm trying to avoid using $scope. Is there a correct or better way to put a listener in a controller than hanging it off $scope?
(function () {
"use strict";
angular
.module("svCodeCamp")
.controller( "SessionListCtrl",
['$scope',"sessionResource",
SessionListCtrl]);
function SessionListCtrl($scope,sessionResource) {
var vm = this;
// WORKS
$scope.interestToggle = function(item) {
debugger;
}
// DOES NOT WORK
vm.interestToggle = function(item) {
debugger;
}
//<td>
//<button ng:click="interestToggle()">Add</button>
//</td>
Global controllers aren't (completely) supported in 1.3.
you should be using:
angular.module("svCodeCamp").controller("SessionListCtrl", ['$scope',"sessionResource", function() {
// controller content
]);
or use this to reenable global controllers:
angular.module('svCodeCamp').config(['$controllerProvider', function($controllerProvider) {
// this option might be handy for migrating old apps, but please don't use it
// in new ones!
$controllerProvider.allowGlobals();
}]);

How do i use $on in a service in angular?

i have been able to get controller to use the $on listener
with $scope.$on.
but i don't see any documentation on how to get services to listen for events.
I tried $rootScope.$on, but that only allows one listener. i want listeners in multiple services regardless of whether their parent controllers are in scope or not.
after experimenting a fair bit it turns out that getting events to the service can be done with minimal code.
sample service code follows in case anyone else runs into this.
The sample saves and restores the service model to local storage when it gets the respective broadcasts
app.factory('userService', ['$rootScope', function ($rootScope) {
var service = {
model: {
name: '',
email: ''
},
SaveState: function () {
sessionStorage.userService = angular.toJson(service.model);
},
RestoreState: function () {
service.model = angular.fromJson(sessionStorage.userService);
}
}
$rootScope.$on("savestate", service.SaveState);
$rootScope.$on("restorestate", service.RestoreState);
return service;
}]);
Since $on is a scope method, you could create a scope in your service, then listen for events on it:
app.factory('myService', function($rootScope) {
var scope = $rootScope.$new(); // or $new(true) if you want an isolate scope
scope.$on('testEvent', function() {
console.log('event received');
})
return {}
});
function MyCtrl($scope, myService, $rootScope) {
$rootScope.$broadcast('testEvent');
}
fiddle
However, I would not recommend this approach, since scopes are not normally associated with services.

"Computed Properties" in AngularJS

I recently chose AngularJS over ember.js for a project I am working on, and have been very pleased with it so far. One nice thing about ember is its built in support for "computed properties" with automatic data binding. I have been able to accomplish something similar in Angular with the code below, but am not sure if it is the best way to do so.
// Controller
angular.module('mathSkills.controller', [])
.controller('nav', ['navigation', '$scope', function (navigation, $scope) {
// "Computed Property"
$scope.$watch(navigation.getCurrentPageNumber, function(newVal, oldVal, scope) {
scope.currentPageNumber = newVal;
});
$scope.totalPages = navigation.getTotalPages();
}]);
// 'navigation' service
angular.module('mathSkills.services', [])
.factory('navigation', function() {
var currentPage = 0,
pages = [];
return {
getCurrentPageNumber: function() {
return currentPage + 1;
},
getTotalPages: function() {
return pages.length;
}
};
});
// HTML template
<div id=problemPager ng-controller=nav>
Problem {{currentPageNumber}} of {{totalPages}}
</div>
I would like for the UI to update whenever the currentPage of the navigation service changes, which the above code accomplishes.
Is this the best way to solve this problem in AngularJS? Are there (significant) performance implications for using $watch() like this? Would something like this be better accomplished using custom events and $emit() or $broadcast()?
While your self-answer works, it doesn't actually implement computed properties. You simply solved the problem by calling a function in your binding to force the binding to be greedy. I'm not 100% sure it'd work in all cases, and the greediness might have unwanted performance characteristics in some situations.
I worked up a solution for a computed properties w/dependencies similar to what EmberJS has:
function ngCreateComputedProperty($scope, computedPropertyName, dependentProperties, f) {
function assignF($scope) {
var computedVal = f($scope);
$scope[computedPropertyName] = computedVal;
};
$scope.$watchCollection(dependentProperties, function(newVal, oldVal, $scope) {
assignF($scope);
});
assignF($scope);
};
// in some controller...
ngCreateComputedProperty($scope, 'aSquared', 'a', function($scope) { return $scope.a * $scope.a } );
ngCreateComputedProperty($scope, 'aPlusB', '[a,b]', function($scope) { return $scope.a + $scope.b } );
See it live: http://jsfiddle.net/apinstein/2kR2c/3/
It's worth noting that $scope.$watchCollection is efficient -- I verified that "assignF()" is called only once even if multiple dependencies are changed simultaneously (same $apply cycle).
"
I think I found the answer. This example can be dramatically simplified to:
// Controller
angular.module('mathSkills.controller', [])
.controller('nav', ['navigation', '$scope', function (navigation, $scope) {
// Property is now just a reference to the service's function.
$scope.currentPageNumber = navigation.getCurrentPageNumber;
$scope.totalPages = navigation.getTotalPages();
}]);
// HTML template
// Notice the first binding is to the result of a function call.
<div id=problemPager ng-controller=nav>
Problem {{currentPageNumber()}} of {{totalPages}}
</div>
Note that with ECMAScript 5 you can now also do something like this:
// Controller
angular.module('mathSkills.controller', [])
.controller('nav', function(navigation, $scope) {
$scope.totalPages = navigation.getTotalPages();
Object.defineProperty($scope, 'currentPageNumber', {
get: function() {
return navigation.getCurrentPageNumber();
}
});
]);
//HTML
<div ng-controller="nav">Problem {{currentPageNumber}} of {{totalPages}}</div>

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