Angular : ng-init does not run on load - angularjs

I have seen a few exmaples on stack overflow about this ng-init issue, although I cant seem to find one which references it with the use of a controller.
I have called the function in the controller by having the following in the html file
<div class="tab-container" ng-controller = "ExampleController" ng-init = "init()" >
In the controller:
$scope.init = function(){
alert("do something");
};
It does run, but it runs before the components have loaded on the screen.
Am i missing something?
Thanks

ng-init is supposed to work like this, because it's used to initialize data.
A very simple example:
<ul ng-init="list = [1,2,3,4]">
<li ng-repeat="l in list"></li>
</ul>
If you are trying to run something while your controller loads, it's actually much simpler than you thought:
app.controller('mainCtrl', function ($scope) {
var init = function ($scope) {
// do whatever you need to do to initialize your controller
$scope.someData = ["Hey", "I'm", "Alive"]
$scope.otherData = localStorage.getItem('myBackup')
}
init()
})
Or even simpler, if you don't need the function (no closures or whatever)
app.controller('mainCtrl', function ($scope) {
// do whatever you need to do to initialize your controller
$scope.someData = ["Hey", "I'm", "Alive"]
$scope.otherData = localStorage.getItem('myBackup')
})
Edit - assuming you're using ngView:
To have the code run on when the page is fully loaded you should set a watcher on the event $viewContentLoaded, like this:
$scope.$on('$viewContentLoaded', function(){
//Here your view content is fully loaded !!
});
app.controller('mainCtrl', function ($scope) {
// This event is triggered when the view has finished loading
$scope.$on('$viewContentLoaded', function() {
$scope.someData = ["Hey", "I'm", "Alive"]
$scope.otherData = localStorage.getItem('myBackup')
})
})

another option is using jquery. It would fit if you depend on many elements. But make sure to load jquery with a version of your choice to project.
loading jquery (insert version where it's ...):
<script src="https://code.jquery.com/jquery-..."></script>
the js code:
$(document).ready(function() {
alert("do something");
});

Related

Why is Angular not updating with a JSON file?

I'm trying to use a simple Angular JS app to load data from a JSON file to a website but it does not work.
The JSON file is:
{"a": "a"}
The Angular app is:
var app = angular.module("app", [])
.controller("ctrl", ["ser", function(ser) {
var vm = this;
ser.getInfo().then(function(data) {
vm.data = data;
});
}])
.service("ser", function() {
this.getInfo = function() {
return $.get("models/model.json");
};
});
The HTML is:
<div ng-controller="ctrl as ctrl">
<p>{{ctrl.data.a}}</p>
</div>
I'm not getting any console errors. I think the problem is related to the lexical scoping for the controller due to the asynchronous getInfo().then() call in the controller, I checked vm inside the function and it is being loaded correctly but doesn't seem to change the ctrl object or Angular is not updating when it does.
I'm serving the app locally.
It works sometimes but most times it doesn't. I can get it to work using $scope but I'm trying to figure out why it's not working now.
It appears you are using jQuery for the ajax. If you modify the scope outside of angular context you need to notify angular to run a digest
Change to using angular $http to avoid such issues
var app = angular.module("app", [])
.controller("ctrl", ["ser", function(ser) {
var vm = this;
ser.getInfo().then(function(response) {
vm.data = response.data;
});
}])
.service("ser", ['$http', function($http) {
this.getInfo = function() {
return $http.get("models/model.json");
};
}]);
DEMO
If it works with $scope that means that without it, Angular is not aware that you performed an asynchronous operation.
I think the following line is using jQuery: return $.get("models/model.json");
So even if you get your data from your function getInfo, it isn't synchronized with the view via vm.data = data;

Updating Controllers/UI Elements In Angular

When working on a project, as these things tend to happen, we came across a situation where we were stumped on how to update certain UI elements when other things were done. For example, the navigation contains a counter of how many pending activities are due today. At any point in time during usage of the app, a user might schedule an activity for later today, and the count section would need to call the API to generate a count and the drop-down items associated with it.
How can I make a navigation controller pull the new list of activities when the main controller makes a change?
See this code for an example.
<div ng-app="TestApp">
<nav ng-controller="navigationController">
<p>The navigation count is: {{items.length}}</p>
</nav>
<div ng-controller="mainController">
<p>The main count is: {{items.length}}</p>
<p>
<button ng-click="addItem()" type="button">Add item.</button>
</p>
</div>
</div>
<script>
var app = angular.module('TestApp', []);
app.factory("api", function() {
return {
update: function() {
return ['a', 'b', 'c', 'd', 'e'];
}
};
});
app.factory("sharedFactory", function(api) {
var obj = {};
obj.items = ["a"];
obj.update = function() {
obj.items = api.update();
};
return obj;
});
app.controller("mainController", function(sharedFactory, $scope) {
$scope.items = sharedFactory.items;
$scope.addItem = function() {
sharedFactory.update();
};
});
app.controller("navigationController", function(sharedFactory, $scope) {
$scope.items = sharedFactory.items;
});
</script>
Our current solution was to create a callback service that other controllers could subscribe to, and then when an activity was created have those callbacks run as needed. This works nicely, but I'm nervous that I'm "doing it wrong".
We're switching to the Angular UI Router, now, so I'm curious if there's a better way of doing so in it. Right now our navigation handler is a stateless controller that hooks into our callback service still.
A nice way to handle this could be to use $scope.$on to listen for events, and $scope.$emit to fire an event going up the scope or $scope.$broadcast to fire an even going down the scope.
In each piece of the UI that needs to be updated can be listening with $scope.$on and update itself when an event is fired, like your user scheduling an event for later today.
Angular docs for $on, $emit and $broadcast
Though I generally think that registering scope values on a controller with a service is the best way to accomplish another option would be to use a factory and set a property of that on scope.
angular.module('app').factory('myService', function() {
var myService = {};
service.count = 0;
/// other service functions
return myService;
}
angular.module('app').controller('myController', function(myService) {
this.count = myService.count;
}
However you feel about MVC, you could use angular's internals to automatically do this:
https://jsfiddle.net/gkmtkxpm/
var myApp = angular.module('myApp', []);
myApp.factory('counter', function() {
return {
count: 0
};
});
myApp.controller('CounterController', function (counter) {
var vm = this;
vm.counter = counter;
vm.increment = function() {
vm.counter.count = vm.counter.count + 1;
};
});
edit:
Concerning your updated question, see the updated fiddle:
https://jsfiddle.net/gkmtkxpm/1/

Calling a scope function in different controller

I have a function defined in a controller , I want to call it in another controller.
I tried to attach it to the $rootscope so I can see in the other controller , but I couldn't .
Is there a way for calling it, without attaching it to the $rootscope?
As far as I know in AngularJS you can share info between controllers in 3 ways:
1 - Creating a Service.
2 - Creating a function linked to $rootScope.
3 - Using events ($broadcast and $on). I use a lot this method in my projects.
I think your problem is that you don't instantiate the controllers in
the proper order or one of them is never instantiated, therefore the
function you want to link to $rootScope in that controller or the broadcast event never fires.
E.G If you want to call a function linked to $rootScope in the 2 controller from the
first one, it is impossible because the 2 controller is instantiated after the first one.
This case happens when you make calls on application runtime.
I will implement your method with some changes:
HTML:
<div ng-controller="MyCtrl_1"></div>
<div ng-controller="MyCtrl_2">
<button ng-click="send()">Send Mess</button>
</div>
JS:
var myApp = angular.module('myApp',[]);
function MyCtrl_1($scope, $rootScope) {
$scope.$on('RenderPage', function (event, PageId) {
$scope.RenderPage = PageId;
alert($scope.RenderPage);
});
};
function MyCtrl_2($scope, $rootScope) {
$scope.MasterPageId = 10;
$scope.send = function(){
$rootScope.$broadcast('RenderPage', $scope.MasterPageId);
}
};
Use carefully $broadcast and $emit, because has different behavior each one.
Try here: http://jsfiddle.net/1ypkb4s9/
Otherwise, post your error.
Simply wrap them with a "father controller":
HTML:
<div ng-app="myApp" ng-controller="myOuterCtrl">
<div ng-controller="myInnerCtrl1">
<button ng-click="outerClick()">Outer Click</button>
</div>
<div ng-controller="myInnerCtrl2">
<button ng-click="innerTwoClick()">Inner Click</button>
</div>
</div>
JS:
angular.module('myApp', []).
controller('myOuterCtrl', function ($scope) {
$scope.outerClick = function () {
console.log('outer click');
}
}).
controller('myInnerCtrl1', function ($scope) {
// nothing here!!
}).
controller('myInnerCtrl2', function ($scope) {
$scope.innerTwoClick = function () {
console.log('inner two click');
}
});
JSFIDDLE.
if you want to use the same function in two or more controllers you might need a service.
or use events
function firstCtrl($scope)
{
$scope.$broadcast('someEvent', [1,2,3]);
}
function secondCtrl($scope)
{
$scope.$on('someEvent', function(event, mass) { console.log(mass); });
}

Angularjs how to call function from another controller?

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

AngularJS access scope from outside js function

I'm trying to see if there's a simple way to access the internal scope of a controller through an external javascript function (completely irrelevant to the target controller)
I've seen on a couple of other questions here that
angular.element("#scope").scope();
would retrieve the scope from a DOM element, but my attempts are currently yielding no proper results.
Here's the jsfiddle: http://jsfiddle.net/sXkjc/5/
I'm currently going through a transition from plain JS to Angular. The main reason I'm trying to achieve this is to keep my original library code intact as much as possible; saving the need for me to add each function to the controller.
Any ideas on how I could go about achieving this? Comments on the above fiddle are also welcome.
You need to use $scope.$apply() if you want to make any changes to a scope value from outside the control of angularjs like a jquery/javascript event handler.
function change() {
alert("a");
var scope = angular.element($("#outer")).scope();
scope.$apply(function(){
scope.msg = 'Superhero';
})
}
Demo: Fiddle
It's been a while since I posted this question, but considering the views this still seems to get, here's another solution I've come upon during these last few months:
$scope.safeApply = function( fn ) {
var phase = this.$root.$$phase;
if(phase == '$apply' || phase == '$digest') {
if(fn) {
fn();
}
} else {
this.$apply(fn);
}
};
The above code basically creates a function called safeApply that calles the $apply function (as stated in Arun's answer) if and only Angular currently isn't going through the $digest stage. On the other hand, if Angular is currently digesting things, it will just execute the function as it is, since that will be enough to signal to Angular to make the changes.
Numerous errors occur when trying to use the $apply function while AngularJs is currently in its $digest stage. The safeApply code above is a safe wrapper to prevent such errors.
(note: I personally like to chuck in safeApply as a function of $rootScope for convenience purposes)
Example:
function change() {
alert("a");
var scope = angular.element($("#outer")).scope();
scope.safeApply(function(){
scope.msg = 'Superhero';
})
}
Demo: http://jsfiddle.net/sXkjc/227/
Another way to do that is:
var extScope;
var app = angular.module('myApp', []);
app.controller('myController',function($scope, $http){
extScope = $scope;
})
//below you do what you want to do with $scope as extScope
extScope.$apply(function(){
extScope.test = 'Hello world';
})
we can call it after loaded
http://jsfiddle.net/gentletech/s3qtv/3/
<div id="wrap" ng-controller="Ctrl">
{{message}}<br>
{{info}}
</div>
<a onClick="hi()">click me </a>
function Ctrl($scope) {
$scope.message = "hi robi";
$scope.updateMessage = function(_s){
$scope.message = _s;
};
}
function hi(){
var scope = angular.element(document.getElementById("wrap")).scope();
scope.$apply(function() {
scope.info = "nami";
scope.updateMessage("i am new fans like nami");
});
}
It's been a long time since I asked this question, but here's an answer that doesn't require jquery:
function change() {
var scope = angular.element(document.querySelector('#outside')).scope();
scope.$apply(function(){
scope.msg = 'Superhero';
})
}
Here's a reusable solution: http://jsfiddle.net/flobar/r28b0gmq/
function accessScope(node, func) {
var scope = angular.element(document.querySelector(node)).scope();
scope.$apply(func);
}
window.onload = function () {
accessScope('#outer', function (scope) {
// change any property inside the scope
scope.name = 'John';
scope.sname = 'Doe';
scope.msg = 'Superhero';
});
};
You can also try:
function change() {
var scope = angular.element( document.getElementById('outer') ).scope();
scope.$apply(function(){
scope.msg = 'Superhero';
})
}
The accepted answer is great. I wanted to look at what happens to the Angular scope in the context of ng-repeat. The thing is, Angular will create a sub-scope for each repeated item. When calling into a method defined on the original $scope, that retains its original value (due to javascript closure). However, the this refers the calling scope/object. This works out well, so long as you're clear on when $scope and this are the same and when they are different. hth
Here is a fiddle that illustrates the difference: https://jsfiddle.net/creitzel/oxsxjcyc/
I'm newbie, so sorry if is a bad practice. Based on the chosen answer, I did this function:
function x_apply(selector, variable, value) {
var scope = angular.element( $(selector) ).scope();
scope.$apply(function(){
scope[variable] = value;
});
}
I'm using it this way:
x_apply('#fileuploader', 'thereisfiles', true);
By the way, sorry for my english
<input type="text" class="form-control timepicker2" ng-model='programRow.StationAuxiliaryTime.ST88' />
accessing scope value
assume that programRow.StationAuxiliaryTime is an array of object
$('.timepicker2').on('click', function ()
{
var currentElement = $(this);
var scopeValues = angular.element(currentElement).scope();
var model = currentElement.attr('ng-model');
var stationNumber = model.split('.')[2];
var val = '';
if (model.indexOf("StationWaterTime") > 0) {
val = scopeValues.programRow.StationWaterTime[stationNumber];
}
else {
val = scopeValues.programRow.StationAuxiliaryTime[stationNumber];
}
currentElement.timepicker('setTime', val);
});
We need to use Angular Js built in function $apply to acsess scope variables or functions outside the controller function.
This can be done in two ways :
|*| Method 1 : Using Id :
<div id="nameNgsDivUid" ng-app="">
<a onclick="actNgsFnc()"> Activate Angular Scope</a><br><br>
{{ nameNgsVar }}
</div>
<script type="text/javascript">
var nameNgsDivVar = document.getElementById('nameNgsDivUid')
function actNgsFnc()
{
var scopeNgsVar = angular.element(nameNgsDivVar).scope();
scopeNgsVar.$apply(function()
{
scopeNgsVar.nameNgsVar = "Tst Txt";
})
}
</script>
|*| Method 2 : Using init of ng-controller :
<div ng-app="nameNgsApp" ng-controller="nameNgsCtl">
<a onclick="actNgsFnc()"> Activate Angular Scope</a><br><br>
{{ nameNgsVar }}
</div>
<script type="text/javascript">
var scopeNgsVar;
var nameNgsAppVar=angular.module("nameNgsApp",[])
nameNgsAppVar.controller("nameNgsCtl",function($scope)
{
scopeNgsVar=$scope;
})
function actNgsFnc()
{
scopeNgsVar.$apply(function()
{
scopeNgsVar.nameNgsVar = "Tst Txt";
})
}
</script>
This is how I did for my CRUDManager class initialized in Angular controller, which later passed over to jQuery button-click event defined outside the controller:
In Angular Controller:
// Note that I can even pass over the $scope to my CRUDManager's constructor.
var crudManager = new CRUDManager($scope, contextData, opMode);
crudManager.initialize()
.then(() => {
crudManager.dataBind();
$scope.crudManager = crudManager;
$scope.$apply();
})
.catch(error => {
alert(error);
});
In jQuery Save button click event outside the controller:
$(document).on("click", "#ElementWithNgControllerDefined #btnSave", function () {
var ngScope = angular.element($("#ElementWithNgControllerDefined")).scope();
var crudManager = ngScope.crudManager;
crudManager.saveData()
.then(finalData => {
alert("Successfully saved!");
})
.catch(error => {
alert("Failed to save.");
});
});
This is particularly important and useful when your jQuery events need to be placed OUTSIDE OF CONTROLLER in order to prevent it from firing twice.

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