unable to get $scope form name on load - angularjs

I'm trying the retrieve the form name inside my angularjs component while the form is being loaded as I wanted to set the form state to dirty based on some data validations that were resolved in to the component. I'm able to access the form name once the form is completely loaded say inside a submit, however i'm unable to do that on the load how can I do that. I'm using ui.router hence the controller name is being set based on the state.
<form class="form-horizontal" name="detail.myForm">
<button ng-click="detail.submit">
</form>
app.component('myDetail', {
bindings: {
alldetails: '<'
},
templateUrl: '/app/detail.html',
controllerAs: 'detail',
controller: function ($state, $transitions, $scope) {
var detail=this;
/*validateData in the alldetails here */
$scope.detail.myForm.$setDirty(); // issue here saying undefined
detail.submit = () =>{
$scope.detail.myForm.$setPristine() //works without any issue
}
}

This happens since the DOM isn't ready on your controller's construction. You have to use the $onInit callback instead. From AngularJS docs:
$onInit() - Called on each controller after all the controllers on an element have been constructed and had their bindings initialized (and before the pre & post linking functions for the directives on this element). This is a good place to put initialization code for your controller.
Also, it'd be better to inject the ngFormController by using the require object instead of assigning it to your model.
Here's a fiddle with a working example. The relevant code is:
.component('myDetail', {
template: '<h1>Details Component</h1>',
controllerAs: 'detail',
// By requiring the form controller, angular will
// create a 'formCtrl' property on your controller with the
// ngFormController instance of the parent form.
require: {
formCtrl: '^form'
},
controller: function() {
// We can't just acces the formController here, couse it will be
// undefined, since the dom isn't ready yet. So we have to use the
// $onInit callback that will be executed by angularjs.
this.$onInit = function() {
/*validateData in the alldetails here */
this.formCtrl.$setDirty();
}
}
});

Related

AngularJS: How a Directive without a Controller can work

just reading a write up from this link http://weblogs.asp.net/dwahlin/creating-custom-angularjs-directives-part-6-using-controllers
it was hard me like novice in ng to understand their code sample. just tell me a example where people would write directive without controller ?
their code
(function() {
var app = angular.module('directivesModule');
app.directive('isolateScopeWithController', function () {
var controller = ['$scope', function ($scope) {
function init() {
$scope.items = angular.copy($scope.datasource);
}
init();
$scope.addItem = function () {
$scope.add();
//Add new customer to directive scope
$scope.items.push({
name: 'New Directive Controller Item'
});
};
}],
template = '<button ng-click="addItem()">Add Item</button><ul>' +
'<li ng-repeat="item in items">{{ ::item.name }}</li></ul>';
return {
restrict: 'EA', //Default in 1.3+
scope: {
datasource: '=',
add: '&',
},
controller: controller,
template: template
};
});
}());
Directive usage:
Attribute: <div isolate-scope-with-controller datasource="customers" add="addCustomer()"></div>
Element: <isolate-scope-with-controller datasource="customers" add="addCustomer()"></isolate-scope-with-controller>
How we can pass customer data directly to directive. basically we have model in controller and populate model and then pass that model data to directive via isolated scope or directive use controller scope. I am very confused the how above code can work, please help me to understand. thanks
The scenario that is being considered implies that the directive will be used in a part of the application, that already has a declared controller, the scope of which contains the properties datasource and add. In turn, new controllers will be instantiated for each of the instances of the directive and will have their own isolate scope.
In reality, it is much more common to create directives that do not have a controller, but rather use the link function. These directives can either rely on the parent controller, sometimes perform DOM manipulation, bind to JS events or simply serve as means to encapsulate part of your application.
You can find a good example of a directive that does not create its own controller here. It is taken from the Angular docs. You will find that it does not even belong to a parent scope in this case meaning that no controller is involved. In reality, an element like this would most probably report to a parent controller, which would then do something with the position.
You can read more about directives, the link function, and how directives work with controllers here.

Angular scopes and binding data to a directive

Consider
angular.module('App').directive('errors',function() {
return {
restrict: 'A',
controller:function() {
var self = this;
self.closeErrors = function() {
self.errors = [];
self.hasErrors = false;
}
},
controllerAs: 'errorsCtrl',
templateUrl: 'errors.html'
}
when called with
<div errors="otherCtrl.errors"></div>
the object errors comes from another controller.
I know i can add
scope: {errors:"="},
and then access it in my controller via
$scope.errors;
but when I assign it to
self.errors = $scope.errors.
self.errors never gets updated when it is changed in the parent.
So my question is, how can I let this work that whenerver my parentcontroller changes the errors object it is also changed in the errorsCtrl.
(Also I do know I can access errors directly in my template without the controller, but I simply want to use my errorsCtrl)
Add bindToController: true to your directive.
http://blog.thoughtram.io/angularjs/2015/01/02/exploring-angular-1.3-bindToController.html
Angular 1.3 introduces a new property to the directive definition
object called bindToController, which does exactly what it says. When
set to true in a directive with isolated scope that uses controllerAs,
the component’s properties are bound to the controller rather than to
the scope.
That means, Angular makes sure that, when the controller is
instantiated, the initial values of the isolated scope bindings are
available on this, and future changes are also automatically
available.

Angular.js: Data binding not working with directives controller option

Why is angular's data binding not working when I specify a controller in the directives controller option? $scope.emailInvalid.text normally should get mapped to type.text but in my case, nothing get's displayed.
JS:
.directive('alert', function () {
return {
template: '<div>{{type.text}}</div>',
restrict: 'E',
scope: {
type: '='
},
controller: function ($scope) {
$scope.emailInvalid = {
text: 'Text Alert Two'
};
}
};
});
HTML:
<alert type="emailInvalid"></alert>
When I define a separate controller and pass it with ng-controller in the HTML, everything works like expected.
Here is a plunker.
Since you want to display type.text you need to define
$scope.type = {
text: 'Text Alert Two'
};
in your directive controller. By doing so, you don't event have to pass the object to the directive.
PLUNKR
OK, I found a solution:
The problem was that angular fails at mapping $scope.emailInvalid to $scope.type. What I have done in my example with <alert type="emailInvalid"></alert>, is passing an object emailInvalid to the directive. Angular is looking for this object in the scopes model of where I used the directive. Obviously this object doesn't exist and angular can't map anything.
The part I was missing is, that the controller I defined with the directives controller option is defined in a different scope than the controller I used with ng-controller.
To work around this problem I'm now passing a string instead of an object and use switch/case to map the alert type.
plunker

$locationChangeSuccess triggers four times

I am new to angular Js.
My application flow is as below:
1) I have a view controller wherein, each view controller sets the breadcrumb data with the help of Breadcrumbs factory.
2) Breadcrumbs factory takes data from view controller and attaches data to $location.$$state object.(reason for storing in state object is if back button is pressed, view controller doesn't instantiate so I can refer history data for breadcrumbs ) below is code to attach data to state object:
var state = $location.state();
state.breadcrumb = breadcrumbData;
$location.replace().state(state);
3) I have also created breadcrumb directive on global header which will display breadcrumbs on $locationChangeSuccess event. Directive will take data from $location.state(); which was set in factory.
My problem is when location is changed, $locationChangeSuccess event callback function executes four times.
below is my directive code:
angular.module('cw-ui')
.directive('cwBreadcrumbs', function($location, Breadcrumbs, $rootScope) {
return {
restrict: 'E',
replace: true,
templateUrl: 'UI/Directives/breadcrumb',
link: function($scope, element){
//some code for element...
$rootScope.$on('$locationChangeSuccess', function(event, url, oldUrl, state, oldState){
// get data from history of location state
var data = $location.state();
console.log(data);
});
}
};
});
output is as below:
Object {}
Object {key: "Core/Views/dash:1", view: "Core/Views/dash", parameters: Array[0], breadcrumb: Array[2]}
Object {key: "Core/Views/dash:1", view: "Core/Views/dash", parameters: Array[0]}
Object {key: "Core/Views/dash:1", view: "Core/Views/dash", parameters: Array[0]}
breadcrumb: Array[2] disappears 1st, 3rd and 4th times. I really don't know what is causing this callback function execute four times, and I have no clue about an issue and don't know how to debug. Please help guys!
After running into this myself, the problem lies in the fact you are using the root scope to bind the locationChangeSuccess event from within a directive that is either encountered multiple times on a single page, or encountered multiple times as you revisit the page:
$rootScope.$on('$locationChangeSuccess', function(event, url, oldUrl, state, oldState){
Since you are binding to the rootScope, and the rootScope does not go out of scope, the event binding is not cleaned up for you.
Inside your link function, you should add a listener for the element $destroy, as well as capture the return value from the original bind, so you can later unbind it.
First: capture return value:
var unbindChangeSuccess = $rootScope.$on('$locationChangeSuccess' ...
Next, unbind that value in your destroy method:
element.on('$destroy', function() {
unbindChangeSuccess();
});
That should solve the multiple calls to your locationChangeSuccess! :)

Sharing scope between controller & directive in AngularJS

I've created a directive to wrap a jQuery plugin, and I pass a config object for the plugin from the controller to the directive. (works)
In the config object is a callback that I want to call on an event. (works)
In the callback, I want to modify a property on the controller's $scope, which does not work. Angular does not recognize that the property has changed for some reason, which leads me to believe that the $scope in the callback is different than the controller's $scope. My problem is I just don't why.
Can anybody point me in the right direction?
Click here for Fiddle
app.js
var app = angular.module('app', [])
.directive('datepicker', function () {
return {
restrict: 'A',
link: function (scope, element, attrs) {
// Uncommenting the line below causes
// the "date changed!" text to appear,
// as I expect it would.
// scope.dateChanged = true;
var dateInput = angular.element('.datepicker')
dateInput.datepicker(scope.datepickerOpts);
// The datepicker fires a changeDate event
// when a date is chosen. I want to execute the
// callback defined in a controller.
// ---
// PROBLEM:
// Angular does not recognize that $scope.dateChanged
// is changed in the callback. The view does not update.
dateInput.bind('changeDate', scope.onDateChange);
}
};
});
var myModule = angular.module('myModule', ['app'])
.controller('MyCtrl', ['$scope', function ($scope) {
$scope.dateChanged = false;
$scope.datepickerOpts = {
autoclose: true,
format: 'mm-dd-yyyy'
};
$scope.onDateChange = function () {
alert('onDateChange called!');
// ------------------
// PROBLEM AREA:
// This doesnt cause the "date changed!" text to show.
// ------------------
$scope.dateChanged = true;
setTimeout(function () {
$scope.dateChanged = false;
}, 5000);
};
}]);
html
<div ng-controller="MyCtrl">
<p ng-show="dateChanged">date changed!</p>
<input type="text" value="02-16-2012" class="datepicker" datepicker="">
</div>
There are a number of scope issues at work in your demo. First , within the dateChange callback, even though the function itself is declared inside the controller, the context of this within the callback is the bootstrap element since it is within a bootstrap handler.
Whenever you change angular scope values from within third party code , angular needs to know about it by using $apply. Generally best to keep all third party scopes inside the directive.
A more angular apprroach is to use ng-model on the input. Then use $.watch for changes to the model. This helps keep all the code inside the controller within angular context. Is rare in any angular application not to use ng-model on any form controls
<input type="text" class="datepicker" datepicker="" ng-model="myDate">
Within directive:
dateInput.bind('changeDate',function(){
scope.$apply(function(){
scope[attrs.ngModel] = element.val()
});
});
Then in Controller:
$scope.$watch('myDate',function(oldVal,newVal){
if(oldVal !=newVal){
/* since this code is in angular context will work for the hide/show now*/
$scope.dateChanged=true;
$timeout(function(){
$scope.dateChanged=false;
},5000);
}
});
Demo: http://jsfiddle.net/qxjck/10/
EDIT One more item that should change is remove var dateInput = angular.element('.datepicker') if you want to use this directive on more than one element in page. It is redundant being used in directive where element is one of the arguments in the link callback already, and is instance specific. Replace dateInput with element
The changeDate event bound to the input seems to be set up to fire outside of the Angular framework. To show the paragraph, call $scope.$apply() after setting dateChanged to true. To hide the paragraph after the delay, you can use $apply() again inside the function passed to setTimeout, but you're likely to keep out of further trouble using Angular's $timeout() instead.
Fiddle

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