Dynamically add angular attributes to old html forms - javascript

I have a project where I'm currently trying to refactor an old system that was hinged on jquery from the ground up with angular 1.x. However, there are a lot of old HTML forms that I'd like to reuse the bulk of so I don't want to recreate them. I'd love it if there was a way to keep it purely angular, but I'm honestly at a loss of how I'd do that (or whether or not I can). I'm fairly new to angular so there are a lot of inner workings to it that I'm still not privy to.
I've searched around on google and other places including here and I can't really even find other people talking about it. That tells me that either I'm searching badly or it's something that I should probably not be working towards.
All the html pages have identically id'd fields so I feel I can reliably base things on that. For example: all forms with first name text boxes have an id of "cl_fname".
Is there anyway that I can accomplish: getting the form, adding an ng-model="cl_fname" or something to the relevant tag and then display the form? I've gotten to the point where I can get the html page, hold it in the scope and then display using ng-bind-html, but figuring out how to add angular attributes to specific elements I can't figure out.

You can achieve this with jQuery and the attr() method.
I created a plunker here that demonstrates adding angular to an existing "plain" html form.
In the example, I'm using id selectors, but you could use any combination of selectors to ensure you get the right elements.
The below is a quick code snippet from my Plunker example:
HTML:
<div ng-app="myApp">
<form id='myForm1' data-test="test2">
<span>First Name:</span>
<input type="text" id="myForm1_firstName" />
<input type="submit" id="myForm1_Submit" value="Go!" />
</form>
</div>
JS:
// set up angular
var myApp = angular.module('myApp', []);
myApp.controller('MyForm1Controller', ['$scope', function($scope) {
$scope.firstName = 'Angular Working!';
}]);
// use jQuery to add the relevent attributes to our form
var jqMyForm1 = $('form#myForm1');
var jqTxtFirstName = jqMyForm1.find('input[type="text"]#myForm1_firstName');
//add controller to form
jqMyForm1.attr('ng-controller', 'MyForm1Controller');
//bind the textbox to the angular 'firstName' variable
jqTxtFirstName.attr('ng-model', "firstName");
EDIT:
just realised you want to load the html form dynamically.
Version 2 of the plunker (here) will now dynamically load a HTML form from an external resource (separate html page), inject it into the current page, add the angular bindings to it, and then get angular to recognise it.
The key to getting angular to recognise the form is the use of the $compile object (angular $compile documentation).
Again, quick snippets of the code in use:
HTML (main page):
<div ng-app="myApp" ng-controller="LoadingController"></div>
HTML (myForm1.html):
<form id='myForm1' data-test="test2">
<span>First Name:</span>
<input type="text" id="myForm1_firstName" />
<input type="submit" id="myForm1_Submit" value="Go!" />
</form>
JS:
// set up angular
var myApp = angular.module('myApp', []);
// main controller for loading the dynamic form
myApp.controller('LoadingController', ['$scope','$http','$compile', function($scope,$http,$compile) {
$scope.loadHtmlForm = function(formURL) {
$http.get(formURL).then(function successCallback(response){
var jqForm = $(response.data);
var jqTxtFirstName = jqForm.find('input[type="text"]#myForm1_firstName');
//add controller to form
jqForm.attr('ng-controller', 'MyForm1Controller');
//bind the textbox to the angular 'firstName' variable
jqTxtFirstName.attr('ng-model', "firstName");
$('div').append(jqForm);
$compile(jqForm[0])($scope);
});
}
$scope.loadHtmlForm('myForm1.html');
}]);
// form controller for managing the data
myApp.controller('MyForm1Controller', ['$scope', function($scope) {
$scope.firstName = 'Angular Working!';
}]);

Related

AngularJS passing data to Javascript variables and opposite

I am looking for a solution on passing data from a specific input text field to AngularJS. it may be a Javascript variable too. If the variable is changed from inside a javascript code it is not updating on AngularJS side. If i take the same variable and in the text field add at least one character or modify something i see variable updating and everything working as it should.
I tried something with angular.element(document.getElementById('ControllerElementID')).scope().funct(); but still no luck. When i update at least one field from the keyboard, all text fields that are related to "ng-model="sig.sigBase6422"" are updating properly as it should. If i call this updates through a JavaScript function i see updates only on specific text field and no updates at all on ng-model happening. How to make it updating as simple as possible? Below i will post a small example. I was able to store data from variable to a external file and in AngularJS read it from file and use it. this is way too long, complicated and ridiculous. I am sure there should be a better way.
Thank you!
<script type="text/javascript">
function addtext1() {document.getElementById("myID1").value = "1111111111111111";}
function addtext2() {document.getElementById("myID2").value = "2222222222222222";}
</script>
<div>
<form action="#" name="FORM1">
<TEXTAREA NAME="sigData" ng-model="sig.sigBase6422" ROWS="10" COLS="20">String: </TEXTAREA>
</form><br>
<input type="text" name="myID1" id="myID1" ng-model="sig.sigBase6422" ><br>
<input type="text" name="myID2" id="myID2" ng-model="sig.sigBase6422" ><br>
<p>Value {{sig.sigBase6422}}!</p>
</div>
<!-- test field -->
Add text 1
Add text 2
Indeed if you want to use AngularJS for what it was created, you have to rewrite your code completely using directive or controller. You variables and functions accessible from the view should be attached to the $scope too.
var myApp = angular.module("myApp", []);
myApp.controller("myCtrl", function($scope){
$scope.addtext1 = function () {
$scope.sig.sigBase6422 += "1111111111111111";
};
$scope.addtext2 = function () {
$scope.sig.sigBase6422 += "2222222222222222";
};
$scope.sig = {
sigBase6422: ""
};
});
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<div ng-app="myApp" ng-controller="myCtrl">
<form action="#" name="FORM1">
<TEXTAREA ng-model="sig.sigBase6422" ROWS="10" COLS="20">String: </TEXTAREA>
</form><br/>
<input type="text" name="myID1" id="myID1" ng-model="sig.sigBase6422" /><br/>
<input type="text" name="myID2" id="myID2" ng-model="sig.sigBase6422" /><br/>
<p>Value {{sig.sigBase6422}}!</p>
<!-- test field -->
<button ng-click="addtext1()">Add text 1</button>
<button ng-click="addtext2()">Add text 2</button>
</div>
You seem to have misunderstood how angular works. What you're trying to do is not how angular works. What you're trying to do with native JavaScript can be done with angular. Angular can update dom and Dom updates angular as it's responsible for causing updates.... anyway without getting any deeper. You need to read more on how angular works and try sticl within the bounds of angular instead of mixing.
That being said :
Tigger change on the Dom element after you have updated its value. Or better yet get access to scope variable on the Dom and call a function in angular with the value you're and set they value from inside of a angular.
Use this code while updating the value.
pick the controller first using
var scope = angular.element(document.getElementById('yourControllerElementID')).scope();
scope.<variablename> = <your operation>;
then
scope.$apply();
the remaining thing will be taken care by Angular.

update angular form from javascript

I'm new to Angular. I've got an Angular js form that has rendered and works properly (updates, etc). I have a scenario where I want to populate form values based on user action after the form has rendered. So if the user takes a certain action, the values in a dropdown box, checkbox, input, etc, are preset in a certain way. I can get everything working except the last step.
From javascript, how do I update the data displayed on the form?
I've gone so far as to use
document.getElementById('123').value = 'my new default'
and although that works for plain text input fields, it doesn't change things like select dropdown boxes. They accept the new value, but still display a blank value. Is there any easy way to do this through the Angular framework?
You can update the value on an html form using angularjs like so:
angular.module('HelloWorldApp', [])
.controller('HelloWorldController', function($scope) {
$scope.greeting = "Hello World";
$scope.UpdateForm = function(){
$scope.greeting= "Updated!";
}
});
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<html>
<div ng-app="HelloWorldApp">
<div ng-controller="HelloWorldController">
<input ng-model="greeting" />
<button ng-click="UpdateForm()">Update Form</button>
</div>
</div>
</html>
To get started with angular, I really enjoyed watching this video
Angular in 50 examples part 1

Disabling submit button based on fields added with ng-bind-html

JSFiddle here: http://jsfiddle.net/c6tzj6Lf/4/
I am dynamically creating forms and buttons and want to disable the buttons if the required form inputs are not completed.
HTML:
<div ng-app="choicesApp">
<ng-form name="choicesForm" ng-controller="ChoicesCtrl">
<div ng-bind-html="trustCustom()"></div>
<button ng-repeat="button in buttons" ng-disabled="choicesForm.$invalid">
{{button.text}}
</button>
</ng-form>
</div>
JavaScript:
angular.module('choicesApp', ['ngSanitize'])
.controller('ChoicesCtrl', ['$scope', '$sce', function($scope, $sce) {
$scope.custom = "Required Input: <input required type='text'>";
$scope.trustCustom = function() {
return $sce.trustAsHtml($scope.custom);
};
$scope.buttons = [
{text:'Submit 1'},
{text:'Submit 2'}];
}]);
choicesForm.$invalid is false and does not change when entering text into the input field.
Solution:
I ended up using the angular-bind-html-compile directive from here: https://github.com/incuna/angular-bind-html-compile
Here is the relevant bit of working code:
<ng-form name="choicesForm">
<div ng-if="choices" bind-html-compile="choices"></div>
<button ng-click="submitForm()" ng-disabled="choicesForm.$invalid">
Submit
</button>
</ng-form>
And choices might be a snippit of HTML like this:
<div><strong>What is your sex?</strong></div>
<div>
<input type="radio" name="gender" ng-model="gender" value="female" required>
<label for="female"> Female</label><br>
<input type="radio" name="gender" ng-model="gender" value="male" required>
<label for="male"> Male</label>
</div>
The main problem is that ngBindHtml doesn't compile the html - it inserts the html as it is. You can even inspect the dynamic input and see that it doesn't have the ngModel's CSS classes (ng-pristine, ng-untouched, etc) which is a major red flag.
In your case, the form simply doesn't know that you've added another input or anything has changed for that matter. Its state ($pristine, $valid, etc) isn't determined by its HTML but by the registered NgModelControllers. These controllers are added automatically when an ngModel is linked.
For example this <input required type='text'> won't affect the form's validity, even if it's required, since it doesn't have ngModel assigned to it.
But this <div ng-model="myDiv" required></div> will affect it since it's required and has ngModel assigned to it.
The ngDisabled directive on your buttons works as expected since it depends on the form's $invalid property.
See this fiddle which showcases how ngModel registers its controller. Note that the html containing the dynamic input gets compiled after 750ms just to show how NgModelControllers can be added after FormController has been instantiated.
There are a few solutions in your case:
use a custom directive to bind and compile html - like this one
use ngInclude which does compile the html
use $compile to compile the newly added HTML but this is a bit tricky as you won't know exactly when to perform this action
This is an answer yet imcomplete because i cannot do the code at the moment.
I think your html will be included, not compiled. So the inputs are not bind to angular and are not part of the angular form object.
The only way i see is to use a directive that will compile the passed html and add it to your form. This may be quite tricky though, if you want to go on this way i suggest to edit your question to ask for the said directive.
However i'm not really familiar with $compile so i don't know if it'll work to just add $compile around $sce.trustAsHtml()
You can write a method as ng-disabled does not work with booleans, it works with 'checked' string instead:
So on your controller place a method :
$scope.buttonDisabled = function(invalid){
return invalid ? "checked" : "";
};
And on your view use it on angular expression :
<button ng-repeat="button in buttons" ng-disabled="buttonDisabled(choicesForm.$invalid)">
Here is a working fiddle
Working DEMO
This is the solution you are looking for. You need a custom directive. In my example I have used a directive named compile-template and incorporated it in div element.
<div ng-bind-html="trustCustom()" compile-template></div>
Directive Code:
.directive('compileTemplate', function($compile, $parse){
return {
link: function(scope, element, attr){
var parsed = $parse(attr.ngBindHtml);
function getStringValue() { return (parsed(scope) || '').toString(); }
//Recompile if the template changes
scope.$watch(getStringValue, function() {
$compile(element, null, -9999)(scope); //The -9999 makes it skip directives so that we do not recompile ourselves
});
}
}
});
I found the directive in this fiddle.
I believe what is really happening though due to jsfiddle I'm unable to dissect the actual scopes being created here.
<div ng-app="choicesApp">
<ng-form name="choicesForm" ng-controller="ChoicesCtrl">
<div ng-bind-html="trustCustom()"></div>
<button ng-repeat="button in buttons" ng-disabled="choicesForm.$invalid">
{{button.text}}
</button>
</ng-form>
</div>
The first div is your top level scope, your form is the first child scope. Adding the div using a function creates the dynamically added input field as a child of the first child, a grandchild of the top level scope. Therefore your form is not aware of the elements you're adding dynamically causing only the static field to be required for valid form entry.
A better solution would be to use ng-inclue for additional form fields or if your form isn't to large then simply put them on the page or template you're using.

What causes AngularJS variable change to fire html update?

I got this example from the W3Schools tutorial on AngularJS. I made a small change from binding the value of the checkbox span to using an expression. I figured that the todo list wouldn't update any more. But it still does. What causes the ng-repeat to fire just because I have added a todo item?
http://plnkr.co/edit/Kojz2ODWDS8dFDNzjYR5?p=preview
<!DOCTYPE html>
<html>
<script src= "http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
<body ng-app="myApp" ng-controller="todoCtrl">
<h2>My Todo List</h2>
<form ng-submit="todoAdd()">
<input type="text" ng-model="todoInput" size="50" placeholder="Add New">
<input type="submit" value="Add New">
</form>
<br>
<div ng-repeat="x in todoList">
<input type="checkbox" ng-model="x.done"> <span>{{x.todoText}}</span>
</div>
<p><button ng-click="remove()">Remove marked</button></p>
<script>
var app = angular.module('myApp', []);
app.controller('todoCtrl', function($scope) {
$scope.todoList = [{todoText:'Clean House', done:false}];
$scope.todoAdd = function() {
$scope.todoList.push({todoText:$scope.todoInput, done:false});
$scope.todoInput = "";
};
$scope.remove = function() {
var oldList = $scope.todoList;
$scope.todoList = [];
angular.forEach(oldList, function(x) {
if (!x.done) $scope.todoList.push(x);
});
};
});
</script>
</body>
</html>
Clicking the Add New Button submits the corresponding form and by using ng-submit="todoAdd()" it will call this function. This in turn adds an entry to the todoList in your scope. As this array has been modified the angular digest cycle is triggered and the list is updated.
Some suggestions for your questions: First of all, you mean W3Schools, not the W3C (which is a standardization organization and normally is not doing tutorials, which is why I got curios - Also, you will find lots of reasons why not to use W3Schools when goolgin around or looking at meta). Also, if you compare to some other code, you should include it or at least link to it.
I found it by googling and it seems your only change is using <span>{{x.todoText}}</span> instead of <span ng-bind="x.todoText"></span>. There really is no difference in terms of the digest cycle here. The only difference is that by using {{}} it might at first be rendered as curly brackets in the browser window, before the variable is actually replaced. Thus, it is usually better to use ng-bind.

ng-click doesn't take parameters from the DOM

I have the following code:
<input id="id">
<button data-action="bea" ng-click="Create($('#id1')[0].value);" class="btn">Insert ID</button>
<button data-action="bea" ng-click="Create($('#id2')[0].value);" class="btn">Insert ID</button>
In the JS I have:
$scope.Create = function (id){
if (id === undefined) {
$scope.data = "You must specify an id";
} else {
$scope.data = data;
console.log(data);
});
}
};
When the call gets into the Create function the value of the id is undefined.
If I add the following line at the beginging of the Create function everything works ok:
id = $('#id')[0].value;
If I send a constant value it works:
<button data-action="bea" ng-click="Create('SomeID');" class="btn">Insert ID</button>
Why is this happening and how can I do that without putting the line of value into the method?
Thanks
This is just an extension of comments and other answers, You could achieve this in many ways using angular, one simple example could be:-
<!-- Add a controller -->
<div ng-controller="MainCtrl">
<!-- Give a model binding to your text input -->
<input ng-model="userEntry" type="text"/>
<!-- ng-click pass which ever argument you need to pass, provided it is an expression that can be evaluated against the scope or any constants -->
<button data-action="bea" ng-click="Create(userEntry);" class="btn">Insert ID</button>
<!-- Some simple data binding using interpolation -->
{{data}}
<!-- Just for demo on repeater on a list of items on the scope -->
<div ng-repeat="item in items track by $index">{{item}}</div>
</div>
Example Demo
My 2 cents on the lines of what were originally trying to do:-
Use angular bindings instead of accessing DOM directly for getting the data, it really helps you deal with just the data without worrying about how to access or render it in DOM. If you think you need to access DOM for implementing business logic re-think on the design, if you really need to do it, do it in a directive. Angular is very opinionated on the design and when where you do DOM access.
ng-model
ng-binding
controller
all about ngmodel controller
This is not the way you should do in AngularJS. You should really think in Angular if you want to use AngularJS. Refer this post ("Thinking in AngularJS" if I have a jQuery background?)
All DOM manipulation should be done in Directive. Refer this page that I found really clear.
(http://ng-learn.org/2014/01/Dom-Manipulations/)
My guess is that $ is not bound to the jQuery function when the ng-click value is evaluated, because it is not exposed in the Angular scope.
Solutions to adress this:
expose the jQuery function in scope somewhere, e.g $scope.$ = $; in a controller.
make the Create function parameterless as you suggested, with a var id = $('#id')[0].value; at the beginning
my favorite : avoid using jQuery. If you put some data in the #id element, there's probably a more natural and AngularJS-idiomatic way of retrieving it than querying the DOM (e.g an Angular service).
In particular, if the element you're targeting is an <input> element, then use the ngModel directive to link the value to a $scopeproperty that will be accessible in the controller :
<input ng-model="inputData"/>
The JavaScript you are trying to pass as a parameter of the create function is not available in the scope of the Create function.
Try to target the element a different way.
Does that help?

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