how to watch the `ng-model` from the form element - angularjs

I am getting data from server and binding to form elements. in case of these datas are edited by the user, i would like to know the status. for that I am trying to watch the object. but i am not getting the result.
what is the correct way to watch the change from the ng-model?
here is my try:
var app = angular.module('plunker', []);
app.controller('MainCtrl', function($scope) {
$scope.issue = {
name:"arr",
age:15
};
$scope.$watch( $scope.issue, function(nv,ov) {
console.log(nv, ov);
}, true)
});
<body ng-controller="MainCtrl">
<form action="">
<input type="text" ng-model="issue.name">
</form>
</body>
Live Demo

Simple answer you'll be happy to know. $watch already presume $scope as its point of watching. so you supply as the first paramter the string value of the variable on $scope you want to watch. If you change
$scope.$watch( $scope.issue, function(nv,ov) {
to
$scope.$watch( "issue", function(nv,ov) {
everything will work :)

$scope.$watch('issue', function(nv,ov) {
console.log(nv, ov);
}, true)

Related

AngularJS - How to pass data from View (HTML) to Controller (JS)

I am really new to AngularJS. I want to pass some object from View (HTML) to my controller (JS).
Actually my Client will send me data in HTML and I have to take that data and process that data in my controller and then display the processed output on screen. He will be using some back-end technology called ServiceNow - https://www.servicenow.com/ .
All the solutions I saw had some event like click event or change event, but in my case this has to be done on page load.
I m using Input type hidden for passing the data to the controller, seems like it's not working.
So is there any other way I can do this ?
Here's the code I am trying to use
<div ng-controller="progressController" >
<input type="hidden" value="ABCD" ng-model="testingmodel.testing">
</div>
app.controller('progressController', function($scope) {
console.log($scope.testingmodel.testing);
});
It says undefined when I console.log my variable in Controller.
You're doing console.log(...) too early. At this time your controller doesn't have any information from the view.
The second problem is that you're binding the view to a variable in controller and not the other way around. Your $scope.testingmodel.testing is undefined and it will obviously the value in the view to undefined.
Solution
Use ng-init to initialize the model and the controller's hook $postLink to get the value after everything has been initialized.
Like this
<div ng-controller="progressController" >
<input type="hidden" ng-model="testingmodel.testing" ng-init="testingmodel.testing = 'ABCD'">
</div>
app.controller('progressController', function($scope) {
var $ctrl = this;
$ctrl.$postLink = function() {
console.log($scope.testingmodel.testing);
};
});
Edit: extra tip
I don't recomment using $scope for storing data since it makes the migration to newer angular more difficult.
Use controller instead.
Something like this:
<div ng-controller="progressController as $ctrl" >
<input type="hidden" ng-model="$ctrl.testingmodel.testing" ng-init="$ctrl.testingmodel.testing = 'ABCD'">
</div>
app.controller('progressController', function() {
var $ctrl = this;
$ctrl.$postLink = function() {
console.log($ctrl.testingmodel.testing);
};
});
You should use the ng-change or $watch
<div ng-controller="progressController" >
<input type="hidden" value="ABCD" ng-model="testingmodel.testing" ng-change="change()">
</div>
app.controller('progressController', function($scope) {
$scope.change = function(){
console.log($scope.testingmodel.testing);
}
});
Or:
app.controller('progressController', function($scope) {
$scope.$watch('testingmodel.testing', function(newValue, olValue){
console.log(newValue);
}
});
If you use ng-change, the function is only called if the user changes the value in UI.
If you use $watch anyway, the function is called.
You can't use value attribute for set or get value of any control, angularJS use ngModel for set or get values.
Here You should try like this way
app.controller('progressController', function($scope) {
//from here you can set value of your input
$scope.setValue = function(){
$scope.testingmodel = {}
$scope.testingmodel.testing = 'ABCD';
}
//From here you can get you value
$scope.getValue = function(){
console.log($scope.testingmodel.testing);
}
});
if you want to bind from html side then you should try like below
<input type="text" ng-model="testingmodel.testing">
<input type="hidden" ng-model="testingmodel.testing">

Values are not showing in a form input AngularJs

Console screenshot I'm having a problem with my code; I'm getting values upon clicking the button, and the same values are also showing in the console. However, I can't see the same values in the input field. Can anyone help with this?
$scope.getFees = function (id) {
getClients.getFeesPoints(id).then(function(response) {
$scope.fees = response.data.fees;
console.log($scope.fees);
});
};
<input type="text" ng-model="fees" class="mdltb-inp fee-inp"
name="fees" placeholder="35$" >
Check link of image 30 is the value of response data
Remove value="{{User}}" from the code and verify $scope.fees = response.data; binds a text value and not an object.
In case if the response.data is an object, that won't bind to an input text field. Find out the appropriate key from response.data object and bind input with that key. Also if the value is not binded still try to call $scope.$apply() after assigning the value
I this you should try this way
var app = angular.module("myapp", []);
app.controller("myCtrl", ['$scope', function($scope) {
$scope.fees="new";
$scope.getFees = function (id) {
//getClients.getFeesPoints(id).then(function(response)
//{
$scope.fees = 50;
console.log($scope.fees);
//});
};
}]);
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="myapp">
<div ng-controller="myCtrl">
<input type="text" class="form-control" id="inputValue" name="uservalue" ng-model="fees" ng-required="true" autofocus="true" ng-blur="checkIfValid()"/>
<button ng-click="getFees(true)">Demo</button>
<h1>{{fees}}</h1>
</div>
</div>
I have Solved this by using $rootScope i.e. "$rootScope” is a parent object of all “$scope” angular objects created in a web page.

AngularJS - two way binding not working using service

I am learning Angular using W3Schools.
I just modified an example about "Services"... The following is the code:
<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<body>
<div ng-app="myApp" ng-controller="myCtrl">
<p><input type="text" ng-model="num"></p>
<h2>{{num}}</h2>
<h1>{{hex}}</h1>
</div>
<p>A custom service whith a method that converts a given number into a hexadecimal number.</p>
<script>
var app = angular.module('myApp', []);
app.service('hexafy', function() {
this.myFunc = function (x) {
return x.toString(16);
}
});
app.controller('myCtrl', function($scope, hexafy) {
$scope.num = 200;
$scope.hex = hexafy.myFunc($scope.num);
});
</script>
</body>
</html>
When I update the textbox, the "HEX" part is not updating. Why?
Your hexafy.myFunc is called only once when the controller is initialized, hence only the initial value is converted to hex. If you want a function to be called on the value change of a scope variable in runtime, you need filters. AngularJS has a lot of inbuilt filters that are ready to use.
You can also define a custom filter, just like you define services or controllers.
<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<body>
<div ng-app="myApp" ng-controller="myCtrl">
<p><input type="text" ng-model="num"></p>
<h2>{{num}}</h2>
<h1>{{num | hexafy}}</h1>
</div>
<p>A custom filter that converts a given number into a hexadecimal number.</p>
<script>
var app = angular.module('myApp', []);
app.filter('hexafy', function() {
return function (x) {
return Number(x).toString(16); // Also convert the string to number before calling toString.
}
});
app.controller('myCtrl', function($scope) {
$scope.num = 200;
//$scope.hex = hexafy.myFunc($scope.num);
});
</script>
</body>
</html>
Further reading: AngularJS Filters
NOTE: A filter is a good idea if you're gonna be using the hexafy functionality at multiple places in/across views. Otherwise, it is just an overkill and the $scope.$watch method will work fine for you, as described in other answers
$scope.hex is not updating because there're no way for it update itself.
The hexafy.myFunc is called only once when the controller is loaded for the first time.
If you want want the $scope.hex property to change with num, you might need a watch on the num property.
$scope.$watch('num', function(newVal, oldVal) {
$scope.hex = hexafy.myFunc($scope.num); /// or newVal
}
The function passed in $scope.$watch will be called everytime the value of $scope.num changes.
for more info see https://docs.angularjs.org/api/ng/type/$rootScope.Scope (the watch section)
Hope it helps.
No need of a service here, you can simple use $watch on the num. See below code snippet, it will update your ui, I have updated your controller code, please check.
app.controller('myCtrl', function($scope, hexafy) {
$scope.num = 200;
$scope.hex = "some default val";
$scope.$watch('num', function(newValue, oldValue) {
$scope.hex = newValue.toString();
});
});
Your Text box is only bind to 'num'. '$scope.hex is not binded to your text box'. So that it is not update when you typing text. You could use '$watch' on 'num'. Read here
app.controller('myCtrl', function($scope, hexafy) {
$scope.num = 200;
$scope.$watch('num', function() {
$scope.hex = hexafy.myFunc(parseInt($scope.num));
});
});

update angularjs model from jquery [duplicate]

I have this simple scenario:
Input element which value is changed by jQuery's val() method.
I am trying to update the angular model with the value that jQuery set. I tried to write a simple directive, but it's not doing what I want.
Here's the directive:
var myApp = angular.module('myApp', []);
myApp.directive('testChange', function() {
return function(scope, element, attrs) {
element.bind('change', function() {
console.log('value changed');
})
}
})
this is the jQuery part:
$(function(){
$('button').click(function(){
$('input').val('xxx');
})
})
and html:
<div ng-app="myApp">
<div ng-controller="MyCtrl">
<input test-change ng-model="foo" />
<span>{{foo}}</span>
</div>
</div>
<button>clickme</button>
Here is the fiddle with my try:
http://jsfiddle.net/U3pVM/743/
Can someone please point me in the right direction?
ngModel listens for "input" event, so to "fix" your code you'd need to trigger that event after setting the value:
$('button').click(function(){
var input = $('input');
input.val('xxx');
input.trigger('input'); // Use for Chrome/Firefox/Edge
input.trigger('change'); // Use for Chrome/Firefox/Edge + IE11
});
For the explanation of this particular behaviour check out this answer that I gave a while ago: "How does AngularJS internally catch events like 'onclick', 'onchange'?"
But unfortunately, this is not the only problem you have. As pointed out with other post comments, your jQuery-centric approach is plain wrong. For more info take a look at this post: How do I “think in AngularJS” if I have a jQuery background?).
Hope this is useful for someone.
I was unable to get the jQuery('#myInputElement').trigger('input') event to be picked up my angular app.
I was however, able to get angular.element(jQuery('#myInputElement')).triggerHandler('input') to be picked up.
The accepted answer which was triggering input event with jQuery didn't work for me. Creating an event and dispatching with native JavaScript did the trick.
$("input")[0].dispatchEvent(new Event("input", { bubbles: true }));
I don't think jQuery is required here.
You can use $watch and ng-click instead
<div ng-app="myApp">
<div ng-controller="MyCtrl">
<input test-change ng-model="foo" />
<span>{{foo}}</span>
<button ng-click=" foo= 'xxx' ">click me</button>
<!-- this changes foo value, you can also call a function from your controller -->
</div>
</div>
In your controller :
$scope.$watch('foo', function(newValue, oldValue) {
console.log(newValue);
console.log(oldValue);
});
You have to use the following code in order to update the scope of the specific input model as follows
$('button').on('click', function(){
var newVal = $(this).data('val');
$('select').val(newVal).change();
var scope = angular.element($("select")).scope();
scope.$apply(function(){
scope.selectValue = newVal;
});
});
I made modifications on only controller initialization by adding listener on action button:
$(document).on('click', '#action-button', function () {
$timeout(function () {
angular.element($('#input')).triggerHandler('input');
});
});
Other solutions did not work in my case.
I know it's a bit late to answer here but maybe I may save some once's day.
I have been dealing with the same problem. A model will not populate once you update the value of input from jQuery. I tried using trigger events but no result.
Here is what I did that may save your day.
Declare a variable within your script tag in HTML.
Like:
<script>
var inputValue="";
// update that variable using your jQuery function with appropriate value, you want...
</script>
Once you did that by using below service of angular.
$window
Now below getData function called from the same controller scope will give you the value you want.
var myApp = angular.module('myApp', []);
app.controller('imageManagerCtrl',['$scope','$window',function($scope,$window) {
$scope.getData = function () {
console.log("Window value " + $window.inputValue);
}}]);
I've written this little plugin for jQuery which will make all calls to .val(value) update the angular element if present:
(function($, ng) {
'use strict';
var $val = $.fn.val; // save original jQuery function
// override jQuery function
$.fn.val = function (value) {
// if getter, just return original
if (!arguments.length) {
return $val.call(this);
}
// get result of original function
var result = $val.call(this, value);
// trigger angular input (this[0] is the DOM object)
ng.element(this[0]).triggerHandler('input');
// return the original result
return result;
}
})(window.jQuery, window.angular);
Just pop this script in after jQuery and angular.js and val(value) updates should now play nice.
Minified version:
!function(n,t){"use strict";var r=n.fn.val;n.fn.val=function(n){if(!arguments.length)return r.call(this);var e=r.call(this,n);return t.element(this[0]).triggerHandler("input"),e}}(window.jQuery,window.angular);
Example:
// the function
(function($, ng) {
'use strict';
var $val = $.fn.val;
$.fn.val = function (value) {
if (!arguments.length) {
return $val.call(this);
}
var result = $val.call(this, value);
ng.element(this[0]).triggerHandler('input');
return result;
}
})(window.jQuery, window.angular);
(function(ng){
ng.module('example', [])
.controller('ExampleController', function($scope) {
$scope.output = "output";
$scope.change = function() {
$scope.output = "" + $scope.input;
}
});
})(window.angular);
(function($){
$(function() {
var button = $('#button');
if (button.length)
console.log('hello, button');
button.click(function() {
var input = $('#input');
var value = parseInt(input.val());
value = isNaN(value) ? 0 : value;
input.val(value + 1);
});
});
})(window.jQuery);
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div ng-app="example" ng-controller="ExampleController">
<input type="number" id="input" ng-model="input" ng-change="change()" />
<span>{{output}}</span>
<button id="button">+</button>
</div>
If you are using IE, you have to use: input.trigger("change");
add .change() after setting the value.
example:('id').val.('value').change();
also don't forget to add onchange or ng-change tag in html
I did this to be able to update the value of ngModel from the outside with Vanilla/jQuery:
function getScope(fieldElement) {
var $scope = angular.element(fieldElement).scope();
var nameScope;
var name = fieldElement.getAttribute('name');
if($scope) {
if($scope.form) {
nameScope = $scope.form[name];
} else if($scope[name]) {
nameScope = $scope[name];
}
}
return nameScope;
}
function setScopeValue(fieldElement, newValue) {
var $scope = getScope(fieldElement);
if($scope) {
$scope.$setViewValue(newValue);
$scope.$validate();
$scope.$render();
}
}
setScopeValue(document.getElementById("fieldId"), "new value");
Not what OP asked, but for any soul that might be as well writing an userscript that goes through input fields and fills the required details. Nothing (fully) worked for me, but finally managed to get it done this way:
var el = $('#sp_formfield_fw_ip');
el.val("some value");
angular.element(el).triggerHandler('focus');
angular.element(el).triggerHandler('input');
angular.element(el).triggerHandler('change');
angular.element(el).triggerHandler('blur');
Open developer tools, and inspect input field for added events. There I found all of them (in my case): focus, input, change and blur.

Perform task after model's DOM is displayed in view

I have a code snippet in my content which is a model fetched from http. I am using syntax highlighter to prettify the code. So I need to call a javascript function as soon as the DOM is updated for that particular model.
Here is a sample code to make it clear. I am using alert to demonstrate it. In my project I would use a third party plugin which will find matching dom elements and remodel them.
Here,
I want the alert to occur after the list is displayed
jsfiddle :
http://jsfiddle.net/7xZde/2/
My controller has something like this.
$scope.items = Model.notes();
alert('test');
alert comes even before the items list is shown, I want it after the list is displayed.
Any hint to help me achieve this.
We need to use $timeout ,
$scope.items = Model.notes();
$timeout(function () {
alert('test');
})
Yeah it was silly , $timeout seemed to be a misnomer to me. I am 2 days old to angularjs . Sorry for wasting your time.
Lucky for you, I wanted to do the exact same thing. Mutation observers are the path forward, but if you need backwards compatibility with older browsers, you'll need a bit more code than this.
Working plunker for Firefox, Chrome, and Safari.
Javascript:
var app = angular.module('plunker', [])
.controller('MainCtrl', function($scope) {
$scope.name = 'World';
})
.directive('watchChanges', function ($parse, $timeout) {
return function (scope, element, attrs) {
var setter = $parse(attrs.watchChanges).assign;
// create an observer instance
var observer = new MutationObserver(function (mutations) {
mutations.forEach(function (mutation) {
$timeout(function () {
var text = angular.element('<div></div>').text(element.html()).text();
setter(scope, text);
});
});
});
// configuration of the observer:
var config = {
attributes: true,
childList: true,
characterData: true,
subtree: true
};
// pass in the target node, as well as the observer options
observer.observe(element[0], config);
};
});
HTML:
<body ng-controller="MainCtrl">
<div watch-changes="text">
<p>Hello {{ name }}</p>
<label>Name</label>
<input type="text" ng-model="name" />
</div>
<pre>{{text}}</pre>
</body>

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