Develop Reference

What is the scope of ngModel directive in AngularJS?

I think that ngModel directive should not create new scope as it needs to make changes in the variables of parent scope.
Please correct me if i am wrong .
And also looking at the source of ngModel directive scope is not defined so it should not create a new scope for directive.
var ngModelDirective = ['$rootScope', function($rootScope) {
return {
restrict: 'A',
require: ['ngModel', '^?form', '^?ngModelOptions'],
controller: NgModelController,
// Prelink needs to run before any input directive
// so that we can set the NgModelOptions in NgModelController
// before anyone else uses it.
priority: 1,
compile: function ngModelCompile(element) {
// Setup initial state of the control
element.addClass(PRISTINE_CLASS).addClass(UNTOUCHED_CLASS).addClass(VALID_CLASS);
return {
pre: function ngModelPreLink(scope, element, attr, ctrls) {
var modelCtrl = ctrls[0],
formCtrl = ctrls[1] || modelCtrl.$$parentForm;
modelCtrl.$$setOptions(ctrls[2] && ctrls[2].$options);
// notify others, especially parent forms
formCtrl.$addControl(modelCtrl);
attr.$observe('name', function(newValue) {
if (modelCtrl.$name !== newValue) {
modelCtrl.$$parentForm.$$renameControl(modelCtrl, newValue);
}
});
scope.$on('$destroy', function() {
modelCtrl.$$parentForm.$removeControl(modelCtrl);
});
},
post: function ngModelPostLink(scope, element, attr, ctrls) {
var modelCtrl = ctrls[0];
if (modelCtrl.$options && modelCtrl.$options.updateOn) {
element.on(modelCtrl.$options.updateOn, function(ev) {
modelCtrl.$$debounceViewValueCommit(ev && ev.type);
});
}
element.on('blur', function() {
if (modelCtrl.$touched) return;
if ($rootScope.$$phase) {
scope.$evalAsync(modelCtrl.$setTouched);
} else {
scope.$apply(modelCtrl.$setTouched);
}
});
}
};
}
};
}];
Also I don't understand why ngModel directive requires ngModel itself.
require: ['ngModel', '^?form', '^?ngModelOptions']
Can't it be ignored and written like
require: ['^?form', '^?ngModelOptions']
If not then please explain why ?

ngModel doesn't create an isolated scope. The reason ngModel is listed in the require array is so that its controller (NgModelController) will be injected into the link function. Notice the ctrls argument that is passed into the ngModelPostLink function. Because ngModel is listed in the array, ctrls[0] will be an instance of the NgModelController. ctrls[1] is the form controller, etc.

Angular directive isolate scope to parent binding undefined

I'm using (the awesome) Restangular and i'm running into something that forces me to use scope.$parent (not awesome), and i don't want to use that. It seems even though my controller is the parent scope to my directive's scope, the = isolated scope binding is evaluated before my parent controller is executed.
With the following HTML:
<div ng-controller="myController">
<div x-my-directive x-some-value="parentValue"></div>
</div>
And the following directive:
myApp.directive("myDirective", function () {
return {
restrict: 'A',
link: function (scope, elem) {
console.log(scope.someValue); // Logs 'undefined' :(
},
scope: {
someValue: "="
}
}
});
And the following controller:
myApp.controller("myController", function($scope, allMyValues) {
allMyValues.getList().then(function(parentValue){
$scope.parentValue = parentValue;
});
}
As shown in my directives link function, evaluating a scope property that should have been bound to my parent's scope property returns undefined. However when i change my directives link function to the following:
myApp.directive("myDirective", function () {
return {
restrict: 'A',
link: function (scope, elem) {
setTimeout(function() {
console.log(scope.someValue); // Logs '{1: number_1, 2: number_2}'
}, 2000);
},
scope: {
someValue: "="
}
}
});
How do i go about resolving this??
Thanks

that should helps:
myApp.controller("myController", function($scope, allMyValues) {
//add this line
$scope.parentValue={};
allMyValues.getList().then(function(parentValue){
$scope.parentValue = parentValue;
});
}
$scope.parentValue not exist until your request is resolved so add line like below to your code
sample demo http://jsbin.com/komikitado/1/edit

Looks like you are waiting for a promise to resolve before assigning the value to the scope.
There are a few ways you might handle this.
One way is to try moving the Restangular call to a resolve function for the view which holds the controller. Then you get access to the resolved data directly as an injection in your controllers
Another way might be to just assign the promise directly to the scope and then in the linking function wait for a resolution.
scope.someValue.then(function(value) { console.log(value); });

Trigger a function in a child directive from it's parent [angularJS]

So I totally do this in reverse all the time when using the directive property require: '^ParentCtrl' inside the child directive. Using require to then call the parent function; however, I need to do this in reverse.
Question:
How do I trigger FROM a parent directive the execution of a function IN a child directive.
Note:
1. Child Directive has no function is inside a link:
2. essentially I want a reverse require.
Parent Directive:
'use strict';
angular.module('carouselApp')
.directive('waCarousel', function() {
return {
templateUrl: 'views/carousel/wa.carousel.html',
controller: function($scope) {
var self = this;
// this function is being called based on how many pages there are
self.carouselElLoaded = function(result) {
var count = 1;
Carousel.params.pageRenderedLength += count;
//when all the pages are loaded
if (Carousel.params.pageRenderedLength === Carousel.params.pageLength) {
Carousel.params.carouselReady = true;
// !!!!!!!! Trigger will go here!!!!!!!!!//
ChildCtrl.drawHotspots(); // (**for placement only**)
} else {
Carousel.params.carouselReady = false;
}
};
}
}
})
Child Directive:
'use strict';
angular.module('carouselApp')
.directive('waHotspots', function() {
return {
require: '^waCarousel',
link: function (scope, element, attrs, ctrl) {
//call this directive based on how
scope.drawHotspots = function () {...};
}
})

This is possible by having the parent controller talk to the child controller through a well defined API, that you create. The idea is that you want to maintain loose coupling between the parent and the child directive by having each respective controller knowing as little about each other as possible, but still have enough knowledge to get the job done.
To achieve this, require the parent directive from the child directive, and let the child directive register itself with parent's controller:
Child directive:
require: '^parentDirective',
controller: function(){
this.someFunc = function() {...}
},
link: function(scope,element,attr, parentCtrl){
parentCtrl.register(element);
}
Then in your parent directive, implement the register function, and get the child's controller, and call the child's function when needed:
Parent directive:
controller: function(){
var childCtrl = undefined;
this.register = function (element) {
childCtrl = element.controller();
}
this.callChildFunc = function (){
childCtrl.someFunc();
}
},
link: function (scope,element){
var ctrl = element.controller();
ctrl.callChildFunc();
}

You could always trigger it via a $watch. Just pass in the parent scope value that you want to watch and change it's value.
Parent:
$scope.drawHotspots = false;
Template:
waHotspots the-trigger="drawHotspots"....
Child Directive:
localTrigger: '#' // Receive the value to watch
scope.$watch('localTrigger',function() {
// call drawHotspots if value is set to true
});

Its on old topic but I came here today so might others ...
I think the best approche is to use a Service
angular.module('App').service('SomeService', [SomeService]);
Then inject the service into both the parent and child ...
controller : ['$rootScope', '$scope','SomeService', SomeDirectiveController],
Use the service to talk to each other ...
In their controllers SomeService.setParent(this) and SomeService.setChild(this)
Service would have a field to hold the references :
this.parentCtrl = null;
this.childCtrl = null;//or [] in-case you have multiple childs!
Somewhere in the parent : SomeService.childCtrl.someFunctionInChild()
Or if you want a restricted access , in service make the fields private :
var parentCtrl = null;
var childCtrl = null;//or [] in-case you have multiple childs of the same type!
this.callUserFunc = function(param){childCtrl.someFunctionInChild(param)};
And Somewhere in the parent : SomeService.callUserFunc(myparam)

passing defined object to another custom directive angularjs

so I have this custom directives that you could see below.
myApp.directive('myDirective', function (testService) {
return {
restrict:'EA',
link:function (scope, element, attr) {
//defined the object
var object = new object();
testService.setObject(object);
}
}
});
myApp.directive('mySecondDirective', function (testService) {
return {
restrict:'EA',
link:function (scope, element, attr) {
//call the variable from previous custom directive
console.log(testService.getobject()); -> always return undefined
}
}
});
and this is the html structure where I used the directives above.
<my-directive></my-directive>
<my-second-directive></my-second-directive>
there I want to retreive the object that contains new object() from previous custom directive, but it always return an undefined I wonder how could I do this without using require nor isolated scope as well.. could you guys help me ?
UPDATE
I create a service to provide the facility to set and retreive the object and apparently it returned undefined because I set the custom direcitve this way
<my-second-directive></my-second-directive>
<my-directive></my-directive>
and this is the service
define(
['services/services'],
function(services)
{
'use strict';
services.factory('testService', [function() {
var me = this;
var testObject = '';
return {
setObject: function(object) {
me.testObject = object;
},
getObject: function() {
return me.testObject;
}
}
}
]);
}
);
the thing is that I actually set the html markup like I already mentioned above which is
<my-second-directive></my-second-directive>
<my-directive></my-directive>
so could you give me some advice on how should I do this ?
note* that the passing object actually worked I prefer using services because it will easy to mantain latter. The question is how do I make the object accessible from another directive even though the initiate install of the object (set the object) in the directive that I defined at the html markup, as the last position of the html it self ?
UPDATE this is the PLUNKER that I've been made for you to understand the question it self

You could achieve this by firing a custom event and then listening for it in the second directive. Here's an updated plunker: http://plnkr.co/edit/512gi6mfepyc04JKfiep?p=info
Broadcast the event from the first directive:
app.directive('myDirective', function(testService) {
return {
restrict: 'EA',
link: function(scope, elm, attr) {
var object = {};
testService.setObject(object);
console.log('setting object');
scope.$broadcast('objectSet');
}
}
});
... and then listen for it on the second:
app.directive('mySecondDirective', function(testService) {
return {
restrict: 'EA',
link: function(scope, elm, attr) {
scope.$on('objectSet', function(){
console.log('retrieving object', testService.getObject());
})
}
}
});
You could also pass data along with the event, if you wanted to emit a specific piece of data to be picked up by the second directive.

1). Scope. Since you don't want to use controllers and isolated scope, then you can simply set this object as scope property.
myApp.directive('myDirective', function() {
return {
restrict: 'EA',
link: function(scope, element, attr) {
var object = {};
object.test = 21;
// set object as scope property
scope.object = object;
}
}
});
myApp.directive('mySecondDirective', function() {
return {
priority: 1, // priority is important here
restrict: 'EA',
link: function(scope, element, attr) {
console.log('Retrieve: ', scope.object);
}
}
});
Just make sure you are also defining priority on the second directive (only if both directive a applied to the same element) to make sure it's evaluated in proper turn (should be bigger then the one of myDirective, if omitted it's 0).
2). Service. Another simple solution is to use service. You can inject custom service into both directives and use it storage for you shared object.

Expanding from what #gmartellino said.
Anything that you wanted to do after listening to the event in second directive, can have a callBack method and use it.
app.directive('mySecondDirective', function(testService) {
return {
restrict: 'EA',
link: function(scope, elm, attr) {
// what if I created like this ?
// define the test variable
var test;
scope.$on('objectSet', function(){
//set the variable
test = testService.getObject();
console.log('retrieving object : ', testService.getObject());
//Anything that you wanted to do
//after listening to the event
//Write a callBack method and call it
codeToExecuteAsCallBack();
})
//then use this method to make a call back from the event
//and outside the event too.
var codeToExecuteAsCallBack = function(){
console.log(test);
}
codeToExecuteAsCallBack();
}
}
});
Updated plnkr link

Call directive API method from 'parent' controller in AngularJS

I have a situation where I want to create custom component, which should be reusable and provide public API to change it's state. I am trying to achieve this by building component using directive and controller.
What I desire to do is simply:
customComponent.apiMethod1( Math.floor( Math.random() * 2 ) );
Here is JSFiddle which should explain my case: http://jsfiddle.net/7d7ad/4/
On line 9 ( when user clicks a button ), I want to call line 22 method ( custom component public API method ). Is there anyway to achieve this?

You are looking for Providers. There are three different types: Factories, Services, and Providers. Each is a bit different you can take a look at this summary.
Providers can allow you to share common methods, functions and data between different areas of your application without duplicating code.
Short example - Fiddle
html
<div ng-app="myApp" ng-controller="testController">
<button ng-click="ClickMe()">Random</button>
{{display.value}}
</div>
javascript
angular.module('myApp', [])
.controller('testController', ['$scope','myService', function($scope, myService) {
$scope.display =new myService();
$scope.ClickMe = function() {
$scope.display.apiMethod1();
};
}])
.factory('myService', function() {
function factory() {
this.value = "Hello World";
this.apiMethod1 = function() {
this.value = Math.floor( Math.random() * 2 );
};
}
return factory;
});

You can, in addition to a service, use a parent directive with a controller.
Here is an example of how this might work (service example at the bottom):
app.directive('parentDir', function() {
return {
controller: function($scope, $element) {
var childFuns = [];
this.registerFun = function(func) {
childFuns.push(func);
}
//we will call this using ng-click
$scope.onClick = function(){
childFuns.forEach(function(func){
func.call(null,5)
});
}
}
}
})
And in the child directive:
app.directive('customcomp', function() {
return {
restrict: 'E',
scope: {},
require: '^parentDir', //we "require" the parent directive's controller,
//which makes angular send it as the fourth
//argument to the linking function.
template: '<h2>{{_currentNumber}}</h2>',
link: function(scope, elm, attrs, ctrl) {
scope._currentNumber = 0;
scope.apiMethod1 = function(val) {
scope._currentNumber = val;
};
//call the parent controller's registring function with the function
ctrl.registerFun(scope.apiMethod1);
}
}
});
Each child directive would "register" a function, and those functions can be stored and called from the parent directive in any way you want.
Note that you should use ng-click for events with angular.
FIDDLE
And here is how it might look with a service:
app.service('funcs', function(){
var funcs = [];
this.register = function(func){ funcs.push(func)};
this.call = function(){
funcs.forEach(function(func){
func.call(null,5);
})
}
})
FIDDLE