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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!

If your controller is running twice then check that you're not initializing your Angular app twice (by having it initialized automatically with ng-app and with manual bootstrap). Also check if you have attached your controller to multiple elements (with ng-controller).
can you explain what you mean by "and with manual bootstrap"?
I noticed the duplicate controller behavior in an app I inherited when troubleshooting an issue with logging and seeing the console logs fire twice. The first log fire had a value, but the second was undefined. After removing the HTML ng-controller directive for the controller, the second console log fire that was undefined went away.
if angular.js is getting added twice, then also this can happen

D
Dave Jarvis

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.


This seems the best place to leave this, after many hours of combing my code, don't ask me how, but when I change <div ng-view>... to <div class="ng-view">..., this issue stopped for me. I haven't come across this behavior before, but maybe someone else has this too.
There is a good explanation of this in the docs for ngController, docs.angularjs.org/api/ng/directive/ngController
Are there any ways to declare a controller in the route, and then another controller on the html page itself? How to ensure both works and no conflicts? Or is this unnecessary?
It is probably unnecessary, maybe use a couple of directives instead?
@Josh leaving it in the HTML reduces flexibility. You're tying your template directly to one controller. You can use ctrl as syntax with routing.
D
Daniel Nalbach

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.


Duplicated anwser. The author already replied saying the same. Just scroll down until the end of the page.
I found it confusing that the author put it as a side note while it is obviously the correct way to do it. The quote from the docs answers the question clearly. And im sure many would find the link to the doc helpful.
This solved my problem of the controller being executed twice. All I did was remove the ng-controller in the template and now its only executing once.
C
Community

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.


5. if you are on Rails, you should remove turbolinks gem from your application.js file. That made me crazy, wasted whole day to discover that. Real pain. Found answer here
6. Initializing the app twice with ng-app and with bootstrap. stackoverflow.com/questions/15535336/…
Thanks . For me, the thing which worked was putting slash at the end of the route
Thanks a million, was breaking my head over this. ended up being number 7! (always the last one...).
Wow, believe it or not, I went through everything on your list, and I'm still having the issue.
D
DontRelaX

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.


It helped me, i was using ng-show / ng-hide instead of ng-if, I had two ng-view, it is not a probleme but ng-if disable while ng-show/ng-hide doesn't
Thanks a ton. This approach solved my problem. Was calling the same ui-view twice which called the controller twice.
g
gb2d

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


what is the solution for this?
Use only one or the other.
f
fracz

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.


C
Community

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:

https://i.stack.imgur.com/AWufV.png

I'd strongly recommend the first thing on anyone's list is to disable it per the post before altering code.


This was my issue. The plugin runs a double instance of your Angular app so it can provide scope info (don't know why it can't just use the initial instance).
I'm glad it helped, it took me a loooong time to figure this out.
u
user3901016

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


a
athina.bikaki

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.


p
pleerock

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!


Also if you are using UI-Router, specifying the directive name for the ui-view inside a class seems to result in a double execution. Changing it to E or fixes the double execution issue.
c
codeful.element

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.


L
Luke Eller

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'
    }
  }
});

m
mg1075

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(...).


M
M. Arnold

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.


S
Sherin Syriac

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.


H
Harry Lime

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


C
Community

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


A
AlexDEV.pro

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".


k
kernal_lora

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?


m
maksbd19

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


B
B.Ma

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.


T
Tom

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.


D
Dumber_Texan2

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="">

N
Nandu Prajapati

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.