I'm new on Angularjs and I'm trying to build my first application. Let's say I have to routes that loads two different views:
127.0.0.1:8080/site
127.0.0.1:8080/site_details
Maybe having two different routes is not the right procedure but that it is another problem.
I have two controllers:
Controller 1:
app.controller('controller_1', function($scope, $http, user) {
user.set('Test Example')
});
and Controller 2
app.controller('controller_2', function($scope, $http, user) {
var xxx = user.get()
});
What I want to do is to share data between these two controllers. To do that I did a service in this way:
app.factory('user', function($rootScope) {
var savedData = {}
function set(data) {
savedData = data;
}
function get() {
return savedData;
}
return {
set: set,
get: get
}
});
By looking around it seems that having a service built like this should solve the problem. However, what I obtain with the function get() in controller 2 is always an empty return.
By setting breakpoints I can see that both set() and get() functions enters in their respective function in the service.
Is this a correct procedure to share data between controllers belonging of different routes?
EDIT1
The two views are built in the same ways and the are loaded inside ng-view
<html ng-app="app" ng-controller='controller_1'>
CONTROLLER 1
</html>
First, sharing data between a service is a correct approach.
In your case, you need to ensure the order of getting data is after setting data.
Using a $timeout is not a good approach, i think there should be another way, it depend on your detail code.
If your data is set after some event, you just need to pay attention to the order sequence like 'get after data has been set'
If you have to set data in initialization of controller_1, and controller_2 is sibling of controller_1, you can put the initialization logic of user data before bother controller_1 and controller_2 is entered.
I think you had giving factory reference to both html where first and
second controller you given have. in that case you have to give factory referee to main single page where your also loading sub pages(where you kept ng-view)
The problem occurs because, controller_1 was not created before the creation of controller_2. You can modify the controller_2 to introduce some delay using $timeout:
app.controller('controller_2', function($scope, $timeout, $http, user) {
// The time out is added to check your code working,
// You can replace the code or can use, its up to your requirement
$timeout(function(){
var xxx = user.get();
console.log(xxx);
}, 500);
});
Using $timeout will allow some time for creation of controller_1.
Also instantiate the controller_2:
<html ng-app="app">
<body>
........
<div ng-controller='controller_1'>
<div ng-controller='controller_2'>
</div>
</div>
</body>
</html>
You can use rootscope like below.
app.controller('controller_1', function($scope, $http, $rootScope) {
$rootScope.UserInfo ="Test Example";
});
app.controller('controller_2', function($scope, $http, $rootScope) {
var xxx = $rootScope.UserInfo;
console.log(xxx)
});
Related
I have the same issue with this post Pass Angular scope variable to Javascript . But I can't achive my solution with their answers.
My Angular Controller
angular.module('App').controller('HomeController', [
'$rootScope', '$scope', '$state', '$timeout', 'ReportService', 'MsgService',
function($rootScope, $scope, $state, $timeout, ReportService, MsgService) {
$scope.$on('$viewContentLoaded', function() {
console.log('HomeController');
$scope.get_locations();
});
// get locations
$scope.get_locations = function() {
var data = {};
// call http get to my api
MsgService.get_all_locations(data, function(response) {
if (response.code == 1) { // success
$scope.locations_array = response.data; // data that I want to access to script
} else {
alert(response.message);
}
});
}
}
]);
My Html
<div id="map" ng-controller="HomeController">{{locations_array}}</div> // {{locations_array}} scope have the result that I want
<script type="text/javascript">
$(document).ready(function() {
var data = $('[ng-controller="HomeController"]').scope().$parent.locations_array;
console.log(data); // underfined
//var $element = $('#map');
// var scope = angular.element($element).scope();
// console.dir(scope.$parent.locations_array); // underfined
});
</script>
I tried access from browser develop tool then It can access scope. But My code can't access this.
How to solve this?
The immediate problem here is a timing issue - you are trying to read the locations_array value off the scope long before the value is populated.
The sequence of events is something like this:
ready event for document triggers, and before Angular has even thought about starting, your inline JS code runs, trying to read the value from the scope, which doesn't exist yet.
Angular bootstraps your Angular application in response to the document's ready event (this may be before #1, depending on the order of scripts on the page). This will call the HomeController constructor, that only sets up a listener for the $viewContentLoaded event.
The $viewContentLoaded event gets broadcast, and you initiate an asynchronous request for the locations.
When that returns with the locations some time later, it populates them on the scope.
Don't rely on .scope()
In addition to the timing issues, there is another major problem with your solution - it relies on the debug information being included by AngularJS. Obviously, it is by default, but it is possible to disable this debug information for significant performance gains in production.
If someone else comes along, possibly after you have left, and tries to disable debug information to improve performance or for some other reason (it is a recommended practice in production), it will stop .scope() from working.
So by relying on .scope(), you are making it so that disabling debug info, a best practice and performance booster, is not possible now or in the future for your app, because it will break things. And it won't be at all obvious to that developer that it would break anything.
So relying on .scope() for anything other than debugging should always be a very last resort.
So what do I do instead?
Like I mentioned, this is a timing problem - you need to wait until the locations are eventually loaded before running code that relies on them.
Luckily, we have many options in JS to deal with asynchronous values - callbacks, promises, RxJS observables, etc. Pick your favourite.
Example: using a global promise
In your controller, create a promise on the global scope (icky, but it needs to be outside Angular somewhere), and resolve that promise with the location data when it is loaded.
var resolveLocations;
window.locationsPromise = new Promise(function (resolve) {
resolveLocations = resolve;
});
angular.module('App').controller('HomeController', [
'$rootScope', '$scope', '$state', '$timeout', 'ReportService', 'MsgService',
function($rootScope, $scope, $state, $timeout, ReportService, MsgService) {
$scope.$on('$viewContentLoaded', function() {
console.log('HomeController');
$scope.get_locations();
});
// get locations
$scope.get_locations = function() {
var data = {};
// call http get to my api
MsgService.get_all_locations(data, function(response) {
if (response.code == 1) { // success
resolveLocations(response.data); // resolve the promise
$scope.locations_array = response.data; // data that I want to access to script
} else {
alert(response.message);
}
});
}
}
]);
Then, your normal (non-angular) javascript (which needs to run after your Angular javascript file is loaded) could use that promise to do something with the data when available:
<script type="text/javascript">
$(document).ready(function() {
window.locationsPromise.then(function (locations_array) {
console.dir(locations_array);
// do something with the data
});
});
</script>
There is probably a better way
Without knowing why you think you need access to this data outside of Angular, it's hard to say for sure, but there are likely other better ways of handling the interplay between Angular code and other Javascript code that depends on it.
Maybe you create a directive to integrate a jQuery plugin, or another service, or whatever, but since AngularJS code is just normal JS, there is no need to think of them as separate from each other. You just have to get the timing right so you have the data available. Good luck!
I have a factory that needs to listen for a broadcast event. I injected $scope into the factory so I could use $scope.$on. But as soon as I add $scope to the parameter list I get an injector error.
This works fine:
angular.module('MyWebApp.services')
.factory('ValidationMatrixFactory', ['$rootScope', function($rootScope) {
var ValidationMatrixFactory = {};
return ValidationMatrixFactory;
}]);
This throws an injector error:
angular.module('MyWebApp.services')
.factory('ValidationMatrixFactory', ['$scope', '$rootScope', function($scope, $rootScope) {
var ValidationMatrixFactory = {};
return ValidationMatrixFactory;
}]);
Why can't I inject $scope into a factory? And if I can't, do I have any way of listening for events other than using $rootScope?
Because $scope is used for connecting controllers to view, factories are not really meant to use $scope.
How ever you can broadcast to rootScope.
$rootScope.$on()
Even though you can't use $scope in services, you can use the service as a 'store'. I use the following approach inspired on AltJS / Redux while developing apps on ReactJS.
I have a Controller with a scope which the view is bound to. That controller has a $scope.state variable that gets its value from a Service which has this.state = {}. The service is the only component "allowed" (by you, the developer, this a rule we should follow ourselves) to touch the 'state'.
An example could make this point a bit more clear
(function () {
'use strict';
angular.module('app', ['app.accounts']);
// my module...
// it can be defined in a separate file like `app.accounts.module.js`
angular.module('app.accounts', []);
angular.module('app.accounts')
.service('AccountsSrv', [function () {
var self = this;
self.state = {
user: false
};
self.getAccountInfo = function(){
var userData = {name: 'John'}; // here you can get the user data from an endpoint
self.state.user = userData; // update the state once you got the data
};
}]);
// my controller, bound to the state of the service
// it can be defined in a separate file like `app.accounts.controller.js`
angular.module('app.accounts')
.controller('AccountsCtrl', ['$scope', 'AccountsSrv', function ($scope, AccountsSrv) {
$scope.state = AccountsSrv.state;
$scope.getAccountInfo = function(){
// ... do some logic here
// ... and then call the service which will
AccountsSrv.getAccountInfo();
}
}]);
})();
<script src="https://code.angularjs.org/1.3.15/angular.min.js"></script>
<div ng-app="app">
<div ng-controller="AccountsCtrl">
Username: {{state.user.name ? state.user.name : 'user info not available yet. Click below...'}}<br/><br/>
Get account info
</div>
</div>
The benefit of this approach is you don't have to set $watch or $on on multiple places, or tediously call $scope.$apply(function(){ /* update state here */ }) every time you need to update the controller's state. Also, you can have multiple controllers talk to services, since the relationship between components and services is one controller can talk to one or many services, the decision is yours. This approach focus on keeping a single source of truth.
I've used this approach on large scale apps... it has worked like a charm.
I hope it helps clarify a bit about where to keep the state and how to update it.
I've a many functions which is repeated in many controllers and for now I just copy and paste it there but what I want is to create 1 global function and inject and call it in all controller.
for example :
<div ng-bind="mycustomreturn(scopeVal)"></div>
which is the best way to do it in service or in root scope I dont want my root scope to be very large so please suggest if we can do it by service
TIA
The best way to share data in angular is by using Services:
angular.module('test', []).service('MyService', function() {
this.mycustomreturn = function() {}
})
.controller(function(MyService) {
// you have two ways
//One:
$scope.MyService = MyService;
// and the view will be:
//<p>{{MyService.mycustomreturn()}}</p>
//Two:
$scope.mycustomreturn = MyService.mycustomreturn();
// and the view will be:
//<p>{{mycustomreturn}}</p>
});
I have a directive which is associated with one controller and the functions in my controller defined as
MyFormController.prototype.addNewRow = function addNewRow() {
//Adding row code
};
I want to call this method from another controller, possible ways?
I ve user the service and moved the code into that service which is shared across the controllers, however the service code does the DOM manipulation, and then i guess the next question would be that can we use $compile in a service test case
service or factory is used to share data between controller.so it would be best to define function in service and factory.
demo:
(function() {
angular.module('app', [])
.service('svc', function() {
var svc = {};
svc.method = function() {
alert(1);
}
return svc;
})
.controller('ctrl', [
'$scope', 'svc', function($scope, svc) {
svc.method();
}
]);
})();
You should not!!!
That defeats the whole purpose of modularity.
If possible try to make the function generic and create a service/factory. Now both the places where you need, use the same generic function defined in service and do their stuff.
Otherwise you can also look at events to make changes accordingly.
Look at this blog post:
http://ilikekillnerds.com/2014/11/angularjs-call-controller-another-controller/
Last but the worst solution is (avoid using this, this is literally an aweful way) is catching the element inside directive and getting its scope and taking the function from it.
Example,
var otherControllerFunc = $(".inside-directive").scope().yourfunc;
I have checked some of the topics for this matter and i got an understanding of controllers are there to initiate scope and i need to use services for this matter but i dont know how.
so here is the problem. i have index page which body has only one div and inside the div i have ng-include listening to a function called viewFile() which is described on controllerA. on the first initial attempt i load a view called login.html and display it. when users logs in and its successful, which are handled in controllerB, i return a token and now i want to load main.html page using viewFile() in controllerA. is there a call back function or notify controller or something for this? or can i write a service that takes care of this for me?
I'm not using ngRoute because i dont want my URL to change to mysite.com/#/login.html and then mysite.com/#/main.html
.controlle("A", function ($scope, sharedVariable){
$scope.token = sharedVariable.getToken();
$scope.viewFile = function(){
if($scope.token == "")
return "view/Login.html";
else
return "view/main.html";
}
}
.controller("B", function ($scope, $http, sharedVariable)){
http({
get ...
.success: function(data){
$scope.token = sharedVariable.setToken();
// INVOKE viewFile from above controller
}
})
}
and here is the index.html body part
<body>
<div ng-controller="A"><ng-include src="viewFile()"></ng-include></div>
</body>
look at this simple example http://jsfiddle.net/derkoe/T85rg/presentation/ here personService.person is shared between two controllers similarly you can write your viewFile function in one service like personService. Then call personService.viewFile from any controller. You can pass $scope as its argumen. Something like below
var myModule = angular.module('myModule', []);
myModule.factory('myService', function($rootScope) {
var sharedService = {};
sharedService.viewFile = function($scope) {
if($scope.token == "")
return "view/Login.html";
else
return "view/main.html";
};
return sharedService;
});
If you want to change the view using different condition define you viewFile function in some service or put it in routescope. Then you can call it from multiple controllers. But I don't think without refresh angularjs will be able to load a different view html