how to make custom directive in angular? - angularjs

I am trying to make custom directive in angular .I try to add input field in my view when I click on button .In other words I am trying to make one custom directive in which when user press the button it add one input field in the browser .I think it is too easy if I am not use custom directive Mean If I use only controller then I take one array and push item in array when user click on button and button click is present on controller.
But when need to make custom directive where I will write my button click event in controller or directive
here is my code
http://play.ionic.io/app/23ec466dac1d
angular.module('app', ['ionic']).controller('appcontrl',function($scope){
$scope.data=[]
}).directive('inputbutton',function(){
return {
restrict :'E',
scope:{
data:'='
},
template:'<button>Add input</button> <div ng-repeat="d in data"><input type="text"></div>',
link:function(s,e,a){
e.bind('click',function(){
s.data.push({})
})
}
}
})
I just need to add input field when user click on button using custom directive ..could you please tell me where i am doing wrong ?
can we make button template and click event inside the directive

The reason it doesn't work is because your registering your click handler with jQuery. So when the click handler fires it is out of the scope of angular so angular does not know it needs to update its bindings.
So you have two options, the first is to tell angular in the click handler, 'yo buddy, update your bindings'. this is done using $scope.$apply
$apply docs: https://docs.angularjs.org/api/ng/type/$rootScope.Scope#$apply
e.bind('click',function(){
s.$apply(function() {
s.data.push({});
});
});
However angular already has built in directive for handling things like mouse clicks you can just use that and let angular do the work for you. This would be the better option.
so first in your view register a click handler on your button
<button ng-click="add()">Add input</button> <div ng-repeat="d in data"><input type="text"></div>
Then in your link simply add the add() method of your scope
s.add = function () {
s.data.push({});
}
Heres a working fiddle showing both examples. http://jsfiddle.net/3dgdrvkq/
EDIT: Also noticed a slight bug in your initial click handler. You registering a click but not specifying the button to apply it to. So if you clicked anywhere in the directive, not just the button, the handler would fire. You should be more specific when registering events manually, using ids, class names attributes etc.
The e or element property of the link function is a jqlite or full jQuery object of the entire directive. If you have jQuery included before angular it will be a full jQuery object. If not it will a jqlite object. A thinned out version of jQuery.

Here is a basic example for your logic .
var TestApp = angular.module('App', []);
// controller
TestApp.controller('mainCtrl', function mainCtrl($scope) {
$scope.data = [];
$scope.addDataItem = function () {
$scope.data.push({
someFilield: 'some value'
});
console.log('pushing value ... ');
}
});
// view
<div ng-app="App" class="container" ng-controller="mainCtrl">
<button type="button" ng-click="addDataItem()">Add an input</button>
<div ng-repeat="d in data track by $index">
<custom-directive model="d"></custom-directive>
</div>
</div>
// directive
TestApp.directive('customDirective', function customDirective() {
return {
restrict: 'E',
scope: {
model: '='
},
template: 'item -> <input type = "text" />',
link: function (scope, elem, attrs) {
console.log('scope.model', scope.model);
},
controller: function ($scope) {
// do staff here
}
}
});

Related

How to handle click events from inside of the directive?

I have a modal component that takes an object with binding (ng-model). Something like:
<modal ng-model="modals.createContact"></modal>
I'm checking for $ctrl.ngModel.show to show/hide the modal:
<div class="modal" ng-show="$ctrl.ngModel.show" ng-transclude></div>
I show/hide modal by setting modals.createContact.show using ng-click directive:
<button ng-click="modals.createContact.show = true"></button>
But this solution is hard to maintain.
I need a directive something like this to toggle modal's show property:
<button modal="modals.createContact">Toggle modal</button>
Directive should listen the click event of the element (button) then toggle the $ctrl.modal.show property.
What I mean with toggling is:
$ctrl.modal.show = !$ctrl.modal.show;
How can achieve this scenario using directives?
To handle click events inside a directive be sure to use $apply:
app.directive("myDirective", function() {
return {
link: postLink
}
function postLink(scope, elem, attrs) {
elem.on("click", function(ev) {
scope.$apply(function() {
//code here
});
});
}
})
AngularJS modifies the normal JavaScript flow by providing its own event processing loop. This splits the JavaScript into classical and AngularJS execution context. Only operations which are applied in the AngularJS execution context will benefit from AngularJS data-binding, exception handling, property watching, etc... You can also use $apply() to enter the AngularJS execution context from JavaScript.
For more information, see
AngularJS Developer Guide - Integration with the browser event loop

AngularJs DOM manipulation in directive

I have a directive which shows a list of Users with their names as links.
Inside the the template of this directive I have following loop:
<ng-repeat="user in myctrl.users />
<a href="" >{{user.name}}</a>
Now I want to add an attribute directive to all the anchor tags with
with name edit-confirm-popup as shown below.
<ng-repeat="user in myctrl.users />
<a href="" edit-confirm-popup>{{user.name}}</a>
What I want to do is whenever user click on link of user's name I want to show a popup with popup's html inserted as sibling of the anchor element. I don't want to repeat the popup html when directive is compiled rather I want to insert it dynamically when user clicks on the link.
I am able to achieve following things :
1) attaching click event listener on directive element that is anchor element in directive's link function.
Don't know
i) how I should insert the template as I want to?
ii) I want the current user to be available in event listener so that I can check some conditions before I show the popup.
Here is my directive code :
function editConfirmPopup() {
function linkFunction(scope, iElement, iAttrs){
console.log(iElement);
iElement.on('click',function onEditUser(e){
console.log(e);
console.log('in event handler');
});
}
var directiveDefinitionObject = {
restrict: 'A',
scope: {
user: '=',
populateUser : '&'
},
controller: 'UserEditConfirmController',
controllerAs: 'userEdit',
link : linkFunction,
bindToController: true
};
return directiveDefinitionObject;
}
angular
.module('mymodule')
.directive('editConfirmPopup', editConfirmPopup);
ng-if directive conditionally appends (or removes) - not just shows/hides - the elements on which it operates.
Using the fact that ng-repeat creates a child scope for each iteration, you can then just use a simple toggle variable to decide whether to show/hide the additional HTML (that you call "popup"):
<div ng-repeat="user in myctrl.users">
<a ng-click="showPopup = !showPopup">{{user.name}}</a>
<div ng-if="showPopup">
The "popup" HTML
</div>
</div>

Adding class to element using Angular JS

I know how to add a class on click of a button in 'jQuery'
$('#button1').click(function(){
$('#div1').addClass('alpha');
});
I want to achieve same thing by angular js. I have a controller - myController1. Can someone help me do it eazily?
AngularJS has some methods called JQlite so we can use it. see link
Select the element in DOM is
angular.element( document.querySelector( '#div1' ) );
add the class like .addClass('alpha');
So finally
var myEl = angular.element( document.querySelector( '#div1' ) );
myEl.addClass('alpha');
You can use ng-class to add conditional classes.
HTML
<button id="button1" ng-click="alpha = true" ng-class="{alpha: alpha}">Button</button>
In your controller (to make sure the class is not shown by default)
$scope.alpha = false;
Now, when you click the button, the $scope.alpha variable is updated and ng-class will add the 'alpha' class to your button.
Use the MV* Pattern
Based on the example you attached,
It's better in angular to use the following tools:
ng-click - evaluates the expression when the element is clicked (Read More)
ng-class - place a class based on the a given boolean expression (Read More)
for example:
<button ng-click="enabled=true">Click Me!</button>
<div ng-class="{'alpha':enabled}">
...
</div>
This gives you an easy way to decouple your implementation.
e.g. you don't have any dependency between the div and the button.
Read this to learn about the MV* Pattern
Try this..
If jQuery is available, angular.element is an alias for the jQuery function.
var app = angular.module('myApp',[]);
app.controller('Ctrl', function($scope) {
$scope.click=function(){
angular.element('#div1').addClass("alpha");
};
});
<div id='div1'>Text</div>
<button ng-click="click()">action</button>
Ref:https://docs.angularjs.org/api/ng/function/angular.element
First thing, you should not do any DOM manipulation in controller function.
Instead, you should use directives for this purpose. directive's link function is available for those kind of stuff only.
AngularJS Docs : Creating a Directive that Manipulates the DOM
app.directive('buttonDirective', function($timeout) {
return {
scope: {
change: '&'
},
link: function(scope, element, attrs) {
element.bind('click', function() {
$timeout(function() {
// triggering callback
scope.change();
});
});
}
};
});
change callback can be used as listener for click event.
querySelector is not from Angular but it's in document and it's in all DOM elements (expensive). You can use ng-class or inside directive add addClass on the element:
myApp.directive('yourDirective', [function(){
return {
restrict: 'A',
link: function(scope, elem, attrs) {
// Remove class
elem.addClass("my-class");
}
}
}
For Angular 7 users:
Here I show you that you can activate or deactivate a simple class attribute named "blurred" with just a boolean. Therefore u need to use [ngClass].
TS class
blurredStatus = true
HTML
<div class="inner-wrapper" [ngClass]="{'blurred':blurredStatus}"></div>
In HTML
To add the class named alpha, assign any variable like showAlpha to false first and then set it to true on click.
<div data-ng-class="{'alpha' : showAlpha}"> </div>
<button ng-click="addClass()"> </button>
In JS file
$scope.showAlpha = false;
$scope.addClass = function(){
$scope.showAlpha = true;
}
try this code
<script>
angular.element(document.querySelectorAll("#div1")).addClass("alpha");
</script>
click the link and understand more
Note: Keep in mind that angular.element() function will not find directly select any documnet location using this perameters
angular.element(document).find(...) or $document.find(), or use the standard DOM APIs, e.g. document.querySelectorAll()

ng-click stops working after the first use of $compile when using nested directives

I have an Angular modal directive that uses a helper/wrapper directive. This way I can always use the same wrapper and just load a different template where needed for different modal content.
PROBLEM: This snippet works, but only for the first life cycle of the modal. So I can fire the modal, close the modal and fire it again. But once the modal is open the second time none of the ng-click directives work. Any tips would be just super.
Usage
<button my-modal="views/login.html">Launch Login-specific Modal</button>
Directive Module (app.js)
angular.module('myModal',[])
.directive('modalWrapper', function(){
return {
replace: true,
templateUrl: 'views/modal.html',
controller: function($scope, $element){
$scope.close = function(){
$element.remove();
};
// NOTE: I use this array to showcase that ng-repeat still works the second time although ng-click stops functioning properly.
$scope.others = ["One", "Two", "Three"];
}
}
})
.directive('myModal', function( $compile){
function link(scope, element, attr){
scope.partial = attr.myModal; // NOTE: Loads sub template via ng-include
var ngModal = $compile('<div modal-wrapper></div>')(scope);
element.on('click', function(){
angular.element('body').append(ngModal);
});
scope.yo = function(){
alert("Yo from inside template.");
};
}
return {
link: link,
scope: {}
}
});
Templates
modal.html
<div class="my-modal">
<p>Modal Wrapper</p>
<div ng-include="partial"></div>
<button ng-click="close()">Close</button>
<p>This just proves that other directives still work (ng-repeat), but ng-click does not.</p>
<div ng-repeat="stuff in others">
<p>{{stuff}}</p>
</div>
</div>
login.html
<h1>Well hey there, I'm the login template.</h1>
<button ng-click="yo()">Say Yo</button>
I think the problem is that you are destroying the scope on which the ng-click is compiled.
When scope.close() is called, an $element.remove() occurs. This both removes the element from the DOM, and destroys the scope to which it is attached. This will result in your ng-click being de-registered.
Unfortunately (as of last time I checked), element.detach() also destroys scope, so your best bet is to compile and append the element to body only once. After this you can use element.show() and element.hide() to show and hide the modal. Alternatively you can recompile the modal each time you want to show it.

AngularJS event for when model binding or ng-repeat is complete?

We have a large model and it takes a couple seconds for ng-repeat to bind all the items in the model to the form. We would like to show a spinner while it this is happening. Is there some event that fires when binding is complete so we know when to hide the spinner?
Plunkr: http://plnkr.co/edit/GzzTW4?p=preview
Use ng-show on the spinner If you are using 1.2 use ng-if
<div ng-controller="Ctrl">
<div ng-show="complete">Complete={{complete}}</div>
<div class="thing" ng-repeat="thing in things" my-post-repeat-directive>
thing {{thing}}
</div>
</div>
In your directive use $last to determine if rendering is done and then change the variable that you have the ng-show/ngif defined on.
function Ctrl($scope) {
$scope.complete=false;
$scope.doComplete = function() {
$scope.complete = true;
}
$scope.things = [
'A', 'B', 'C'
];
}
angular.module('myApp', [])
.directive('myPostRepeatDirective', function() {
return function(scope, element, attrs) {
if (scope.$last) {
scope.$eval('doComplete()');
}
};
});
You can watch for $last item compile/link function, and fire a custom event to the scope
In that kind of situations, I use the $timeout service mixed with the $viewContentLoaded event fired by angular ui router (if you use ui router) :
about $timeout :
This service is just a simple decorator for $timeout service that adds a "flush" and "verifyNoPendingTasks" methods.
about $viewContentLoaded
fired once the view is loaded, after the DOM is rendered. The '$scope' of the view emits the event.
My personal usecase is for a paymentForm to dynamically generate its hidden inputs (using HTML data computed serverside that I insert through ng-bind-html) and submit to the payment Gateway :
$scope.$on('$viewContentLoaded', function() {
$timeout(function () {
$scope.paymentForm.submit();
});
});
FYI in the above code example, .submit() is a function from a custom directive used with the form in order to be able to autosubmit the form.
Julien
For this I normally create a spinner div in your view with an ng-show="submitting". Then when the data is loaded, you set the $scope.submitting to 'false' show the spinner is hidden.
<!-- In your HTML -->
<div class="spinner" ng-show="submitting">
<div ng-repeat="p in people">
{{p.name}}
</div>
//In Javascript
$scope.submitting = true;
$scope.load_data = function(){
$http.get('/api/route')
.then(function(success){
$scope.submitting = false;
},function(error){
console.log(error);
});
}
I hope that helps

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