angularjs controller executes twice - angularjs

A similar question was asked here but it did not help me.
I am learning angularjs and I noticed the controller is executed twice.
I have a very simple fiddle example that shows the behavior here
I built the example as I was learning about services and at first I thought it was the injecting of the services into the controller but I commented all the code related to the services and still the controller is executed twice.
My example works but I am afraid I am doing something wrong.
<div ng-app="MyApp">
<div ng-controller="MyCtrl">
{{data1}}
</div>
</div>
var app = angular.module('MyApp', [])
app.service('Service1', function(){
return {
ajxResponse1: 'dataFromService1'
};
});
function MyCtrl($scope, Service1){
alert('Entering MyCtrl');
$scope.data1 = Service1.ajxResponse1;
alert('Exiting MyCtrl');
}

One possible source is this: if you are using Routing and specify the controller in routes - you must not specify it in template that the route uses. We had that problem when this was overlooked.

Your controller was running twice in the fiddle because angular is referenced twice (once via the Frameworks & Extensions drop down and another as an External Resource).
See this updated fiddle where I removed the External Resource and the alerts only show up once.
The code remains unchanged:
function MyCtrl($scope, Service1, Service2, Service3){
alert('Entering MyCtrl');
$scope.data1 = Service1.ajxResponse1;
$scope.data2 = Service2.ajxResponse2;
$scope.data3 = Service3.ajxResponse3;
alert('Exiting MyCtrl');
}

I had a similar problem and it was due to slashes in my routing.
I had something like /post{slug:[a-z0-9-]*/} for my route and when visiting the page at domain.com/post it would redirect to the version with a slash on the end.
Took me ages to work it out!
Edit:
Actually, just took a more detailed look at your code and noticed there is no routing in there, so this is probably not the cause in your case.
Might be useful for people like me who were looking for a different solution though.

For all the people using rails and angularjs:
The rails framework that maps URLS to views and loads them clashes with the angularjs $route even when you have a single-view application.
To prevent the double-loading of your controller:
go to application.js and remove "//= require turbolinks
You're welcome.

Related

Combining Angular controllers

I have an existing angular project that has something really weird with the controller. It looks like the following.
app.controller('AppController', ['$scope', function ($scope) {
var app = app_application;
angular.extend($scope, app);
$scope.itTransports = app.state.itTransports;
}]);
I have a proof of concept for something I am trying to do on this fiddle and an attempt to mix the above controller and my concept in this fiddle but I cant seem to get it to work. I think it is something to do with the weird way the above controller works but I cant break it too badly and cant talk to the previous developer. I would think that if a combination cant be done then I would need some way for one controller to call another one but I want to make sure before I go down that path.
Edit: My main goal is to add functionality to check if the cookie exists. I am trying to do this in the same controller just for simplicity sake, but like I said before I am not adding a new one.
If you have some common functionality that you want to access from multiple controllers (e.g. checking if a cookie exists) then you should put that functionality into a service and inject that service into both controllers.

Changes to scope on click are not being updated across my app

Started using Angular last week, read/watched many tutorials and I'm currently trying to build a newsfeed type application.
Here's the skinny: I have a service that gets data from the server. On the newsfeed itself I have two controllers: one that has the entire newsfeed in its scope and another that has an instance for each newsfeed article. If the user clicks an icon on an individual post it should call a service that has been injected into both controllers and then broadcasts a message that the main controller picks up. The main controller then updates a variable in a filter, filtering the newsfeed content based on the user's selection.
Here's the problem: Everything works fine except that the main controller doesn't update the bound variable in the HTML. I have read close to every SO article on two-way binding within an ng-repeat and the related struggles, but in my case the bound variable falls outside an ng-repeat, hence why I'm posting.
The code:
services.factory('filterService', function() {
var filterService = {};
filterService.filterKey = '';
filterService.getFilter = function() {
return filterService.filterKey;
};
filterService.setFilter = function(name) {
filterService.filterKey = name;
$rootScope.$broadcast('changeFilter');
};
return filterService;
});
app.controller('CommentCtrl', function($scope, $timeout, $http, filterService) {
$scope.setSearchParam = function(param) {
alert('clicked: ' + param)
filterService.setFilter(param);
}
app.controller('FeedCtrl', function($scope, articles, filterService, $timeout) {
$scope.articles = articles;
$scope.model = {
value: ''
};
$scope.$on('changeFilter', function() {
console.log(filterService.filterKey);
$scope.model.value = filterService.filterKey
}
});
});
<div class="articles">
<div class="articleStub" ng-repeat="article in articles|filter:model.value">
<div ng-controller="CommentCtrl">
<div class="{{article.sort}}">
<div class="leftBlock">
<a href="#" ng-click="setSearchParam(article.sort)">
<div class="typeIcon">
<i ng-class="{'icon-comments':article.question, 'icon-star':article.create, 'icon-ok-sign':article.notype}"></i>
</div>
</a>
Note: the FeedCtrl controller is called in the app.config $routeprovider function thing whatever its called
Edited to add: the alert and console checks both work, so I'm assuming the issue is not in the filterService or CommentCtrl.
Here's the Plnkr: http://plnkr.co/edit/bTit7m9b04ADwkzWHv88?p=preview
I'm adding another answer as the other is still valid, but is not the only problem!
Having looked at your code, your problems were two fold:
You had a link to href="#"
This was causing the route code to be re-run, and it was creating a new instance of the controller on the same page, but using a different scope. The way I found this out was by adding the debug line: console.log("running controller init code for $scope.$id:" + $scope.$id); into script.js under the line that blanks the model.value. You'll notice it runs on every click, and the $id of the scope is different every time. I don't fully understand what was happening after that, but having two of the same controller looking after the same bit of the page can't be a good thing!
So, with that in mind, I set href="". This ruins the rendering of the button a bit, but it does cure the problem of multiple controllers being instantiated. However, this doesn't fix the problem... what's the other issue?
angular.element.bind('click', ....) is running 'outside the angular world'
This one is a bit more complicated, but basically for angular data-bindings to work, angular needs to know when the scope gets changed. Most of the time it's handled automagically by angular functions (e.g. inside controllers, inside ng-* directives, etc.), but in some cases, when events are triggered from the browser (e.g. XHR, clicks, touches, etc.), you have to tell angular something has changed. You can do this with $scope.$apply(). There are a few good articles on the subject so I'd recommend a bit of reading (try here to begin with).
There are two solutions to this - one is to use the ng-click directive which wraps the native click event with $scope.$apply (and has the added advantage that your markup is more semantic), or the other is to do it yourself. To minimise the changes to your code, I just wrapped your click code in scope.$apply for you:
element.bind('click', function() {
// tell angular that it needs to 'digest' the changes you're about to make.
scope.$apply(function(){
var param = scope.article.sort;
filterService.setFilter(param);
})
});
Here's a working version of your code: http://plnkr.co/edit/X1AK0Bc4NZyChrJEknkN?p=preview
Note I also set up a filter on the list. You could easily ad a button to clear it that is hidden when there's no filter set:
<button ng-click="model.value=''" ng-show="model.value">Clear filter</button>
Hope this helps :)
I actually think the problem is not that your model.value isn't getting updated - all that code looks fine.
I think the problem lies in your filter.
<div class="articleStub" ng-repeat="article in articles|filter:model.value">
This filter will match any object with any field that contains model.value. What you actually want to do is the following:
<div class="articleStub"
ng-repeat="article in articles|filter:{sort: model.value}:true">
To specify that you only want to match against the sort property of each article. The final true parameter means that it'll only allow strict matches as well, so ed wouldn't match edward.
Note that | filter:{sort: model.value}:true is an angular expression, the :s are like JavaScript commas. If you were to imagine it in JavaScript it would be more like: |('filter',{sort:model.value}, true) where | is a special 'inject a filter here' function..
EDIT:
I'm finding it hard to debug your example without having the working code in front of me. If you can make it into a plunker I can help more, but in the meantime, I think you should try to make your code less complicated by using a different approach.
I have created a plunker that shows an easy way to filter a list by the item that you click. I've used very little code so hopefully it's quite easy to understand?
I would also recommend making your feed items into a directive. The directives can have their own controller so it would prevent you having to do the rather ugly repeating of a ng-controller.

Dynamically loading AngularJS modules from within Templates (Views)

Background: Let's suppose for the sake of argument that you have 100,000 views (partials). Let's also suppose you have accompanying view-scoped controllers, and potentially view-scoped services and filters as well. Try to envision an aggregating application that hosts 100,000 disparate small applications.
Issue: When you have "partials" that require accompanying controllers, the typical solution is to do something like this:
$routeProvider.when('/app1', {
templateUrl: 'partials/view1.html',
controller: 'controller1'
});
The controller is typically loaded from index.html via:
<script src="js/directives/Controller1.js"></script>
The problem with this approach is that it doesn't scale. There are solutions out there for dynamically loading controllers, but they still require adding touch points in various config.
Ideal Solution: Ideally - again for very small applications whose numbers are in the 000's, the controller could be loaded dynamically, and from within the partial itself. This would alleviate the need to manage several files and several configuration touch points (not to mention network requests), and keep each partial very well contained.
It would look something like this:
In router:
$routeProvider.when('/apps/:appId', {
templateUrl: 'partials/app-frame.html',
controller: 'AppCtrl'
});
In containing html (app-frame) include the relatively disparate "mini app":
<h1>Currently hosting {{appId}}</h1><hr>
<div class="ng-include: appUrl"></div>
In partial resolved with appUrl, define controller and markup in one:
<script>
myApp.controller('controller1', ['$scope', function ($scope) {
$scope.foo = "bar";
}]);
</script>
<div ng-controller="controller1">
{{foo}}
</div>
For cases like this, where there are a lot of partials and a 1-1 mapping for controller and view, it can make sense to couple the two for development efficiencies and maintenance. It's a lot cleaner than using several files and additional configuration touch points.
The problem is, this doesn't work. It could be as simple as forcing the script to load prior to applying the directive... but not sure how to do that?
Here are some similar explanations of the problem:
https://groups.google.com/forum/#!topic/angular/H4haaMePJU0
Loading Partial Page With Angular and Compile The Controller
Igor from the AngularJS team says:
I see.. we looked into supporting script tags in jqlite, but what needs to be done to get a cross-browser support involves a lot of black magic. For this reason we decided that for now we are just going to recommend that users use jquery along with angular in this particular case. It doesn't make sense for us to rewrite one third of jquery to get this working in jqlite.
But I don't know what he means by "use jquery" ... JQuery is already loaded into the application from index.html (and prior to angularjs), but it sounds like I need to do something specifically within the partial itself.
You cannot add new controllers through module('app').controller(name, function() { .. }) after AngularJS bootstrap. In order make it work you should use $controllerProvider.register(name, function() { .. }).
You can override the original controller registering function in following way to be able to add controllers pre and pos bootstrap:
var app = angular.module('app', [
'ui.router'
]);
app.config(function($controllerProvider) {
app.controller = function (name, controller) {
$controllerProvider.register(name, controller);
};
});

Structuring RequireJS + AngularJS

I'd like to work with both angularjs and requirejs. Before that, I worked with backbonejs and requirejs. I felt a bit more comfortable with that combination.
I also got the bower-seed from github, but it's too nested for the beginning.
Here's what I don't understand:
Require forces me to bootstrap angular myself.
Therefore I create a module named by my app.
Then I bootstrap that module to the document.
angular.module('app', []);
angular.bootstrap(document, ['app']);
That happens after the document ist ready, which is checked by this function:
angular.element(document).ready(function() { ... bootstraping ... }
So far I get it. But how and at what point do I put the ng-app into the header?
app.js has the function to put all my controllers, routers etc. into the app. By returning all modules I loaded inside the require-module. In my case I only load controllers
///app.js///
define(['angular', 'controller'], function (angular){
return angular.module('app',[
'app.controller',
'app.router'
]);
});
My controller:
define(['index', 'uirouter'], function(controllers){
controllers.controller('homeCtrl', function($scope, $routeParams){
$scope.logId = "testId";
});
});
Each controller puts it's content in a collection inside the index-module
my Index file:
///index///
define(['angular'], function(angular){
return angular.module('app.controllers',[]);
});
The Index file returs the controller-module to every controller-file requiring it. So I have all controllers in one module, by loading different controller-files
Here's my question: is this procedure correct and can I go on loading all angular-modules like this?
Im confused by working with angular-modules and require-modules ... Maybe anyone got a nice instruction in how to set up a angular-require project easily :)
Here's a link to the project:LINK ;)
Maybe anyone could help me a little bit :)
I am experimenting with this example: https://github.com/nikospara/angular-require-lazy
I also mentioned it in this SO question.
It needs work, but it is working; discussion on this topic really interests me.

Combating AngularJS executing controller twice

I understand AngularJS runs through some code twice, sometimes even more, like $watch events, constantly checking model states etc.
However my code:
function MyController($scope, User, local) {
var $scope.User = local.get(); // Get locally save user data
User.get({ id: $scope.User._id.$oid }, function(user) {
$scope.User = new User(user);
local.save($scope.User);
});
//...
Is executed twice, inserting 2 records into my DB. I'm clearly still learning as I've been banging my head against this for ages!
The app router specified navigation to MyController like so:
$routeProvider.when('/',
{ templateUrl: 'pages/home.html',
controller: MyController });
But I also had this in home.html:
<div data-ng-controller="MyController">
This digested the controller twice. Removing the data-ng-controller attribute from the HTML resolved the issue. Alternatively, the controller: property could have been removed from the routing directive.
This problem also appears when using tabbed navigation. For example, app.js might contain:
.state('tab.reports', {
url: '/reports',
views: {
'tab-reports': {
templateUrl: 'templates/tab-reports.html',
controller: 'ReportsCtrl'
}
}
})
The corresponding reports tab HTML might resemble:
<ion-view view-title="Reports">
<ion-content ng-controller="ReportsCtrl">
This will also result in running the controller twice.
AngularJS docs - ngController
Note that you can also attach controllers to the DOM by declaring it
in a route definition via the $route service. A common mistake is to
declare the controller again using ng-controller in the template
itself. This will cause the controller to be attached and executed
twice.
When you use ngRoute with the ng-view directive, the controller gets attached to that dom element by default (or ui-view if you use ui-router). So you will not need to attach it again in the template.
I just went through this, but the issue was different from the accepted answer. I'm really leaving this here for my future self, to include the steps I went through to fix it.
Remove redundant controller declarations
Check trailing slashes in routes
Check for ng-ifs
Check for any unnecessary wrapping ng-view calls (I accidentally had left in an ng-view that was wrapping my actual ng-view. This resulted in three calls to my controllers.)
If you are on Rails, you should remove the turbolinks gem from your application.js file. I wasted a whole day to discover that. Found answer here.
Initializing the app twice with ng-app and with bootstrap. Combating AngularJS executing controller twice
When using $compile on whole element in 'link'-function of directive that also has its own controller defined and uses callbacks of this controller in template via ng-click etc. Found answer here.
Just want to add one more case when controller can init twice (this is actual for angular.js 1.3.1):
<div ng-if="loading">Loading...</div>
<div ng-if="!loading">
<div ng-view></div>
</div>
In this case $route.current will be already set when ng-view will init. That cause double initialization.
To fix it just change ng-if to ng-show/ng-hide and all will work well.
Would like to add for reference:
Double controller code execution can also be caused by referencing the controller in a directive that also runs on the page.
e.g.
return {
restrict: 'A',
controller: 'myController',
link: function ($scope) { ....
When you also have ng-controller="myController" in your HTML
When using angular-ui-router with Angular 1.3+, there was an issue about Rendering views twice on route transition. This resulted in executing controllers twice, too. None of the proposed solutions worked for me.
However, updating angular-ui-router from 0.2.11 to 0.2.13 solved problem for me.
I tore my app and all its dependencies to bits over this issue (details here: AngularJS app initiating twice (tried the usual solutions..))
And in the end, it was all Batarang Chrome plugin's fault.
Resolution in this answer:
I'd strongly recommend the first thing on anyone's list is to disable it per the post before altering code.
If you know your controller is unintentionally executing more than once, try a search through your files for the name of the offending controller, ex: search: MyController through all files. Likely it got copy-pasted in some other html/js file and you forgot to change it when you got to developing or using those partials/controllers. Source: I made this mistake
I had the same problem, in a simple app (with no routing and a simple ng-controller reference) and my controller's constructor did run twice. Finally, I found out that my problem was the following declaration to auto-bootstrap my AngularJS application in my Razor view
<html ng-app="mTest1">
I have also manually bootstrapped it using angular.bootstrap i.e.
angular.bootstrap(document, [this.app.name]);
so removing one of them, it worked for me.
In some cases your directive runs twice when you simply not correct close you directive like this:
<my-directive>Some content<my-directive>
This will run your directive twice.
Also there is another often case when your directive runs twice:
make sure you are not including your directive in your index.html TWICE!
Been scratching my head over this problem with AngularJS 1.4 rc build, then realised none of the above answers was applicable since it was originated from the new router library for Angular 1.4 and Angular 2 at the time of this writing. Therefore, I am dropping a note here for anyone who might be using the new Angular route library.
Basically if a html page contains a ng-viewport directive for loading parts of your app, by clicking on a hyperlink specified in with ng-link would cause the target controller of the associated component to be loaded twice. The subtle difference is that, if the browser has already loaded the target controller, by re-clicking the same hyperlink would only invoke the controller once.
Haven't found a viable workaround yet, though I believe this behaviour is consistent with the observation raised by shaunxu, and hopefully this issue would be resolved in the future build of new route library and along with AngularJS 1.4 releases.
In my case, I found two views using the same controller.
$stateProvider.state('app', {
url: '',
views: {
"viewOne#app": {
controller: 'CtrlOne as CtrlOne',
templateUrl: 'main/one.tpl.html'
},
"viewTwo#app": {
controller: 'CtrlOne as CtrlOne',
templateUrl: 'main/two.tpl.html'
}
}
});
The problem I am encountering might be tangential, but since googling brought me to this question, this might be appropriate. The problem rears its ugly head for me when using UI Router, but only when I attempt to refresh the page with the browser refresh button. The app uses UI Router with a parent abstract state, and then child states off the parent. On the app run() function, there is a $state.go('...child-state...') command. The parent state uses a resolve, and at first I thought perhaps a child controller is executing twice.
Everything is fine before the URL has had the hash appended.
www.someoldwebaddress.org
Then once the url has been modified by UI Router,
www.someoldwebaddress.org#/childstate
...and then when I refresh the page with the browser refresh button, the $stateChangeStart fires twice, and each time points to the childstate.
The resolve on the parent state is what is firing twice.
Perhaps this is a kludge; regardless, this does appear to eliminate the problem for me: in the area of code where $stateProvider is first invoked, first check to see if the window.location.hash is an empty string. If it is, all is good; if it is not, then set the window.location.hash to an empty string. Then it seems the $state only tries to go somewhere once rather than twice.
Also, if you do not want to rely on the app's default run and state.go(...), you can try to capture the hash value and use the hash value to determine the child state you were on just before page refresh, and add a condition to the area in your code where you set the state.go(...).
For those using the ControllerAs syntax, just declare the controller label in the $routeprovider as follows:
$routeprovider
.when('/link', {
templateUrl: 'templateUrl',
controller: 'UploadsController as ctrl'
})
or
$routeprovider
.when('/link', {
templateUrl: 'templateUrl',
controller: 'UploadsController'
controllerAs: 'ctrl'
})
After declaring the $routeprovider, do not supply the controller as in the view. Instead use the label in the view.
In my case it was because of the url pattern I used
my url was like /ui/project/:parameter1/:parameter2.
I didn't need paramerter2 in all cases of state change. In cases where I didn't need the second parameter my url would be like /ui/project/:parameter1/. And so whenever I had a state change I will have my controller refreshed twice.
The solution was to set parameter2 as empty string and do the state change.
I've had this double initialisation happen for a different reason. For some route-transitions in my application I wanted to force scrolling to near the top of the page (e.g. in paginated search results... clicking next should take you to the top of page 2).
I did this by adding a listener to the $rootScope $on $viewContentLoaded which (based on certain conditions) executed
$location.hash('top');
Inadvertently this was causing my routes to be reevaluated and the controllers to be reinitialised
My issue was updating the search parameters like so $location.search('param', key);
you can read more about it here
controller getting called twice due to append params in url
In my case renaming the controller to a different name solved the problem.
There was a conflict of controller names with "angular-ui-tree" module: I renamed my controller from "CatalogerTreeController" to "TreeController" and then this controller starts to be initiated twice on the page where "ui-tree" directive used because this directive uses controller named "TreeController".
I had the same problem and after trying all the answers I finally found that i had a directive in my view that was bound to the same controller.
APP.directive('MyDirective', function() {
return {
restrict: 'AE',
scope: {},
templateUrl: '../views/quiz.html',
controller: 'ShowClassController'
}
});
After removing the directive the controller stopped being called twice. Now my question is, how can use this directive bound to the controller scope without this problem?
I just solved mine, which was actually quite disappointing. Its a ionic hybrid app, I've used ui-router v0.2.13. In my case there is a epub reader (using epub.js) which was continuously reporting "no document found" once I navigate to my books library and select any other book. When I reloaded the browser book was being rendered perfectly but when I selected another book got the same problem again.
My solve was very simple. I just removed reload:true from $state.go("app.reader", { fileName: fn, reload: true }); in my LibraryController
I have the same issue in angular-route#1.6.7, and it because the extra slash in the end of regex route:
.when('/goods/publish/:classId/', option)
to
.when('/goods/publish/:classId', option)
and it works correctly.
Just adding my case here as well:
I was using angular-ui-router with $state.go('new_state', {foo: "foo#bar"})
Once I added encodeURIComponent to the parameter, the problem was gone: $state.go('new_state', {foo: encodeURIComponent("foo#bar")}).
What happened?
The character "#" in the parameter value is not allowed in URLs. As a consequence, angular-ui-router created my controller twice: during first creation it passed the original "foo#bar", during second creation it would pass the encoded version "foo%40bar". Once I explicitly encoded the parameter as shown above, the problem went away.
My issue was really difficult to track down. In the end, the problem was occurring when the web page had missing images. The src was missing a Url. This was happening on an MVC 5 Web Controller. To fix the issue, I included transparent images when no real image is available.
<img alt="" class="logo" src="">
I figured out mine is getting called twice is because i was calling the method twice from my html.
`<form class="form-horizontal" name="x" ng-submit="findX() novalidate >
<input type="text"....>
<input type="text"....>
<input type="text"....>
<button type="submit" class="btn btn-sm btn-primary" ng-click="findX()"
</form>`
The highlighted section was causing findX() to be called twice. Hope it helps someone.

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