I've used both href and ng-href and I couldn't see the difference between them.
Why does Angular have the ng-href attribute, and when should I use it?
From the documentation:
Using Angular markup like {{hash}} in an href attribute will make the link go to the wrong URL if the user clicks it before Angular has a chance to replace the {{hash}} markup with its value. Until Angular replaces the markup the link will be broken and will most likely return a 404 error. The ngHref directive solves this problem.
Effectively, the only place you're using it is for links in which you need to rely on a value provided to the DOM by Angular. If you do not require Angular for a part of that link, or you don't plan on using Angular to generate that link, then you do not need to use ngHref.
If you need to bind values from your model you use the directive. For example:
<div ng-init="address='http://stackoverflow.com/questions/37467603'">
<a ng-href="{{address}}">Dynamic link</a>
<br/>
Change the link dynamically: <input type="text" ng-model="address">
</div>
In the example above, the value of address is programmatically bound to the value in the input text box, which you can change.
If you don't need to be dynamic (i.e. react to a change in the model's state), then you can simply stay with href:
<a href="http://stackoverflow.com/questions/37467603"/>Static link</a>
Related
I want to use ng-model directive as element rather than as attribute inside tag,is there any way to do it?
well I've already designed my webpage in html and javascript and I want to include it in angularJS using "ng-include". So rather than adding attribute like,
<input type="checkbox" id="checkbox" name='rejectedPartsConfirmtodothis' ng-model="reject">
I want to put it in the format like, (as said in angulaJS documentation )
<ng-model>
<input --->
</ng-model>
but this is not working, any idea how can I make it work?
Quoting the content of the page
Usage
as element: (This directive can be used as custom element, but be aware of IE restrictions).
<ng-model>
...
</ng-model>
according to v1.5 official documentation : https://docs.angularjs.org/api/ng/directive/ngModel
Usage
as element: (This directive can be used as custom element, but be aware of IE restrictions).
<ng-model>
...
</ng-model>
I dont really think there would be a use case where you would really need to do this...instead try some alternative but use ng-model as an attribute as ng-model is a pre-defined directive given by angularjs...
You can build a new directive but you cannot modify ng-model to work as an element.
I am creating a directive in which template I need to use the a scope's variable value as the name of the directive (or alternatively controller) to load.
Say I have a directive widget that has a template called widget.html which looks like:
<div class="widget widget.type" {{widget.type}} ng-controller="widget.type">
<div class="navBar">
<div ng-include="widget.type + '-t.html'"></div>
<i class="fa fa-close"></i>
<hr>
</div>
<div ng-include="widget.type + '-f.html'"></div>
</div>
Now widget.type is not getting evaluated in the first line. It works fine for ng-include. Say widget.type's value is weather. The first line should then be interpolated first to look like (doesn't matter if class attribute, widget.type-attr or ng-controller is interpolated)
<div class="widget" weather>
and then compiled to include the weather directive.
How can I get widget.type interpolated in the template?
Not an option is to use ng-include to load the directive. I need to use one common template for the widget and want to add/override/extend the base directive with additonal functionality/Variables.
If this is not the way to achieve that, is there a way to extend a directive the OOP-way?
See the plunkr
You can only place interpolation expressions in text nodes and attribute values. AngularJS evaluates your template by first turning it into DOM and then invoking directive compilation, etc. If you try to place {{...}} instead of attribute name, you'll just end up with messed-up DOM.
If you really need to replace a whole directive based on $scope variable value, you'll need to create a directive for application of other directives and do some heavy lifting with $compile (you'll have to completely re-compile the template each time the value changes). I'd recommend trying to find other designs solving your situation before attempting this.
For adjusting your template based on element attributes, see this answer.
I'm using twitter bootstrap with a popover and got a AngularJS scoped variable to appear correctly. The below works.
(data-content="{{notifications[0].user}} shared {{notifications[0].user_two}}'s records")
When I add the following
(data-content="<b>{{notifications[0].user}} shared {{notifications[0].user_two}}'s records</b>")
No errors show up, but all of the {{}} no longer render.
So I tried this as a test of sorts
(data-content="<div ng-repeat='item in notifications'>test {{item}} <br/><hr/></div>")
Much like the last example, I see the "test" but not the {{item}}. And the "test" only show s up once, even though the notifications had three elements. When I look at the DOM there's this
<div class="popover-content">
<div ng-repeat="item in notifications">you <br><hr></div>
</div>
I've also tried just creating a directive to iterate through the array and make the output I want, but my attempt to set data-content equal to a directive have been failures. The examples I've found elsewhere I'm confident would work, but I just wanted to confirm before I begin implementing something like this (http://tech.pro/tutorial/1360/bootstrap-popover-using-angularjs-compile-service) or (Html file as content in Bootstrap popover in AngularJS directive) that I'm not missing a straightforward fix to the problem I outlined above that would not require me creating a directive.
Edit:
Plunkr Url http://plnkr.co/edit/VZwax4X6WUxSpUTYUqIA?p=preview
html might be breaking it, try marking it as trusted html using $sce
How do you use $sce.trustAsHtml(string) to replicate ng-bind-html-unsafe in Angular 1.2+
$scope.html = '<ul><li>render me please</li></ul>';
$scope.trustedHtml = $sce.trustAsHtml($scope.html);
<button ... data-content="trustedHtml" ...> </button>
I am using this way:
<div ng-cloak>{{ message.userName || message.text }}</div>
Is this the only / best way to ensure the user does not see the {{ }} when AngularJS is still loading ?
There are several ways to hide content before Angular has a chance to run
Put the content you want to hide in another template, and use ngInclude
<div ng-include="'myPartialTemplate.html'"></div>
If you don't actually want another request made to the server to fetch another file, there are a couple of ways, as explained in the $templateCache docs. There are tools to "compile" external HTML templates into JS to avoid having to do this manually, such as grunt-angular-templates.
Similar to ngInclude, if you put everything in custom directives, with its own template, then the template content won't be shown until Angular has had a chance to run.
<my-directive></my-directive>
With a definition of:
app.directive('myDirective', function() {
return {
restrict: 'E',
template: '<div>Content hidden until Angular loaded</div>'
}
});
ngBind as an alternative to {{}} blocks
<div>Hello <span ng-bind="name"></span></div>
ngCloak as you have mentioned (in this list for completeness).
<div ng-cloak>Content hidden until Angular compiled the template</div>
But you must have certain styles loaded before the page is rendered by the browser, as explained in the ngCloak docs.
You can use ng-bind too as the documentation explains.
A typical advantage about ng-bind is the ability to provide a default value while Angular is loading (indeed, ng-cloak can only hide the content):
<p>Hello, <span ng-bind="user.name">MyDefaultValueWhileAngularIsLoading<span/></p>
Then as soon Angular is loaded, the value will be replaced by user.name.
Besides, ng-cloak is useful when dealing with blocks (many HTML lines) and ng-bind on a particular element.
Here is my plnkr: http://plnkr.co/edit/n8cRXwIpHJw3jUpL8PX5?p=preview You have to click on a li element and the form will appear. Enter a random string and hit 'add notice'. Instead of the textarea text you will get undefined.
Markup:
<ul>
<li ng-repeat="ticket in tickets" ng-click="select(ticket)">
{{ ticket.text }}
</li>
</ul>
<div ui-if="selectedTicket != null">
<form ng-submit="createNotice(selectedTicket)">
<textarea ng-model="noticeText"></textarea>
<button type="submit">add notice</button>
</form>
</div>
JS part:
$scope.createNotice = function(ticket){
alert($scope.noticeText);
}
returns 'undefined'. I noticed that this does not work when using ui-if of angular-ui. Any ideas why this does not work? How to fix it?
Your problem lies in the ui-if part. Angular-ui creates a new scope for anything within that directive so in order to access the parent scope, you must do something like this:
<textarea ng-model="$parent.noticeText"></textarea>
Instead of
<textarea ng-model="noticeText"></textarea>
This issue happened to me while not using the ng-if directive on elements surrounding the textarea element. While the solution of Mathew is correct, the reason seems to be another. Searching for that issue points to this post, so I decided to share this.
If you look at the AngularJS documentation here https://docs.angularjs.org/api/ng/directive/textarea , you can see that Angular adds its own directive called <textarea> that "overrides" the default HTML textarea element. This is the new scope that causes the whole mess.
If you have a variable like
$scope.myText = 'Dummy text';
in your controller and bind that to the textarea element like this
<textarea ng-model="myText"></textarea>
AngularJS will look for that variable in the scope of the directive. It is not there and thus he walks down to $parent. The variable is present there and the text is inserted into the textarea. When changing the text in the textarea, Angular does NOT change the parent's variable. Instead it creates a new variable in the directive's scope and thus the original variable is not updated. If you bind the textarea to the parent's variable, as suggested by Mathew, Angular will always bind to the correct variable and the issue is gone.
<textarea ng-model="$parent.myText"></textarea>
Hope this will clear things up for other people coming to this question and and think "WTF, I am not using ng-if or any other directive in my case!" like I did when I first landed here ;)
Update: Use controller-as syntax
Wanted to add this long before but didn't find time to do it. This is the modern style of building controllers and should be used instead of the $parent stuff above. Read on to find out how and why.
Since AngularJS 1.2 there is the ability to reference the controller object directly instead of using the $scope object. This may be achieved by using this syntax in HTML markup:
<div ng-controller="MyController as myc"> [...] </div>
Popular routing modules (i.e. UI Router) provide similar properties for their states. For UI Router you use the following in your state definition:
[...]
controller: "MyController",
controllerAs: "myc",
[...]
This helps us to circumvent the problem with nested or incorrectly addressed scopes. The above example would be constructed this way. First the JavaScript part. Straight forward, you simple do not use the $scope reference to set your text, just use this to attach the property directly to the controller object.
angular.module('myApp').controller('MyController', function () {
this.myText = 'Dummy text';
});
The markup for the textarea with controller-as syntax would look like this:
<textarea ng-model="myc.myText"></textarea>
This is the most efficient way to do things like this today, because it solves the problem with nested scopes making us count how many layers deep we are at a certain point. Using multiple nested directives inside elements with an ng-controller directive could have lead to something like this when using the old way of referencing scopes. And no one really wants to do that all day!
<textarea ng-model="$parent.$parent.$parent.$parent.myText"></textarea>
Bind the textarea to a scope variable's property rather than directly to a scope variable:
controller:
$scope.notice = {text: ""}
template:
<textarea ng-model="notice.text"></textarea>
It is, indeed, ui-if that creates the problem. Angular if directives destroy and recreate portions of the dom tree based on the expression. This is was creates the new scope and not the textarea directive as marandus suggested.
Here's a post on the differences between ngIf and ngShow that describes this well—what is the difference between ng-if and ng-show/ng-hide.