I'm designing an AngularJS 1.5.x app that will have lots of forms and lots of fields per form. I'm finding that I'm repeating attributes a lot, e.g.:
<div class="form-group">
<label class="control-label" for="thing.Field1">Field 1</label>
<input class="form-control ctrl-md"
type="text"
id="thing.Field1"
name="Field1"
ng-model="thing.Field1"
ng-maxlength="30"
required
uib-tooltip="Field 1 is required"
tooltip-placement="right"
tooltip-trigger="none"
tooltip-is-open="thingForm1.Field1.$invalid && showValidationErr('Thing1')"
ng-blur="fieldBlur('Thing1')">
</div>
I've attempted to use a directive + template, and it works more or less, but it seems very complex and slow.
Is there a good way to make the input reusable? Or should I just get used to doing a lot of copy+paste in my editor?
In addition to reducing repetitive coding, it would be nice to be able to change all elements in one place, in the case that I want to change the tooltip position on all fields for example.
There is many ways. Have a look at this library http://angular-formly.com/. In my projects I use plain inputs and writing directives only in a complex cases, like 2 field controls. Or special field like card expiration date.
UPDATE
Ok, have a look at this pls. Angular: better form validation solution
You have 3 solutions:
To store your attributes as it is.
To store a group of attributes, commonly used together, in a directive. Or use directive which utilize array of properties. Like validation directive in my example.
To use directive with transclusion to utilize 1st and 2nd approach. So you can swap elements position (such as label, input control, error hint) in a single place. Plus you can easily create property like... preset on this directive and store attribute presets in it.
So, as I already told, there is many ways to reduce number of attribute repetition.
I wonder if anyone can help. On the surface of it, my question title may sound kind of stupid! I'm trying to use angularjs form validation in a non-angularjs application! Let me try to explain ...
We have a 'traditional' web app. Its not an SPA. The backend is java, and the java app server manages the session and the data within. Each page is a full http request/response. (There are a small number of ajax request/responses, but these are to add some bling to the page, rather than it's core functionality). In this respect, the architecture of the app is very traditional/old-skool, in that the server-side java code is responsible for generating the markup and populating form field values from it's version of the model data held in it's session store. (I think this is the crux of the problem)
The app is predominantly a HTML form based application, and to enhance the UX we have written some javascript field validators based around jQuery. For a number of reasons these have started to get a bit out of control, and we are exploring alternative options.
A simple google search finds countless jQuery plug ins for form validation. We are looking at these, but random jQuery plug ins are not our favoured approach (we tend to steer clear of 'somebloke.com' plug ins because we can't guarantee how well they're written, browser compatibility, future maintenance, how well they work with other plug ins etc - we've had our fingers burnt with this kind of thing before)
So we are looking at other approaches, and are currently exploring the use of angularjs.
Being able to 'gently introduce' angularjs into our architecture has some advantages. It's from a stable best-of-breed organisation (ie. it's not 'somebloke.com') so is well supported and maintained. It encourages us to write our js in a very modular & testable manner (our current rats nest of jQuery plugins, callbacks etc is far from that!). angularjs form validation is based around html5 standards and is declarative and semantic. It gives us a way forward for migrating our other jQuery based code to something better (angularjs directives). And overall, if we can layer angularjs into our current app, it gives us a good foundation for converting the app to a modern SPA at some point in the future.
Rewriting the entire app as an angularjs (or any other mv* framework) SPA at this point in time is not an option, so as mentioned above, we are looking at introducing small bits of functionality at a time; and today's challenge is form validation.
So, that's the background.
I've stripped out our current js client side validation, and our server-side java code is generating markup like this:
<form method="POST" action="/renew">
<input name="firstname" type="text" value="alf" />
<input name="surname" type="text" value="garnet" />
<input name="age" type="number" value="88" />
<input type="submit" />
</form>
(where the values for the input fields have been populated server-side from the model held by the server)
I've added the angularjs library to the page, and have got form validation working as follows:
<form method="POST" action="/renew" novalidate name="renewForm"
ng-controller="yourDetails" ng-submit="submitForm(renewForm, $event)">
<input name="firstname" type="text" value="alf" required ng-model="firstname"/>
<input name="surname" type="text" value="garnet" required ng-model="surname"/>
<input name="age" type="number" value="88" required ng-model="age"/>
<input type="submit" />
</form>
app.controller('yourDetails', function($scope) {
$scope.submitForm = function(form, $event) {
if (!form.$valid) {
$event.preventDefault();
return false;
}
};
});
This is a reasonable starting point. Broadly speaking it works in that angularjs is handling the form validation and submission. The submitForm method is executed, and if the form is not valid then the if block is entered and the form submission is cancelled. From here I can see it would be easy to add in the field error messages etc using ng-show etc.
The problem however is the use of ng-model on each html field. As I understand it I need to use this so that angularjs binds the field to the form, and can therefore track each fields valid status.
However, ng-model also appears to setup the 2-way data binding and sets the value of the field to it's version of the model data ... which is empty. For example:
Our server-side template might contain this:
<input th:field="*{firstname}" type="text" required ng-model="firstname"/>
Which might generate this markup:
<input name="firstname" value="alf" type="text" required ng-model="firstname"/>
The markup that gets served to the client includes value="alf"
But then angularjs steps in and sets up 2-way binding for the field. Because we don't have a firstname property in the angularjs scope, it initialises one with a blank value, and sets that blank value in the DOM of the field.
This results in the page being rendered by the browser with blank values in the fields, even though server-side we have values in the model, and the server has correctly generated the markup etc.
So, I think I understand the core problem and why it's happening. My question is, can I do angularjs form validation without the ng-model attribute on each field, or is there a version of the ng-model directive that only does 1-way binding - specifically DOM -> model
Any help would be very much appreciated;
Thanks
Nathan
When generating your form at server side, you can initialize your model with ng-init:
<input ng-init="firstname='alf'" th:field="*{firstname}" type="text" required ng-model="firstname" />
OK, #Alexandre's answer was almost right, and it was his answer that pointed me in the direction of my final solution (so he should get the credit for this really :) )
ng-init does work as #Alexandre has suggested. The reason I couldn't get it to work was that I was trying to use it on a number field.
The following works because the value being set on the model with ngInit and the html input type are both text/string:
<input ng-init="firstname='alf'" th:field="*{firstname}" type="text" required ng-model="firstname" />
I was trying it on the age field as follows:
<input ng-init="age='88'" th:field="*{age}" type="number" required ng-model="age" />
This does not work because the age property was being set on the model as a string, but the html input type is a number. The following does work:
<input ng-init="age=88" th:field="*{age}" type="number" required ng-model="age" />
This led me to realise that the value being set on the angular model needs to match the data type of the html input type (certainly true of chrome, not sure about other browsers) (ie. string properties in the model - even if they are parse-able as numbers - cannot be used in a html number field with ngModel)
With this in mind, I decided there were 2 options. I could either do it server-side in the code that generates the markup:
<input ng-init="age=(some-potentially-complex-logic-to-workout-whether-its-a-string-or-number)" th:field="*{age}" type="number" required ng-model="age" />
Or I could do it client-side with a custom directive. In the end I went with a custom directive because a) it meant I could have a go at writing a directive (all part of the learning :)) and b) I realised there might be other cases that need special consideration which might make doing it server-side even more complex (ie. select fields don't have a value, they have a selected index of which you need to get it's value; radio buttons all have a value but you only want to set the value of the checked radio)
Here's what I came up with:
angularApp.directive('lvInitializeValueOnScope', function() {
return {
restrict: 'A',
link: function(scope, element, attrs, controller) {
var propertyName = attrs.name,
propertyValue = attrs.value,
elementName = element.get(0).tagName.toLowerCase(),
fieldType = ( elementName === 'input' ? attrs.type.toLowerCase() : elementName ),
// set expression to assume propertyValue is a string value
expression = propertyName + '=\'' + ( !!propertyValue ? propertyValue : '' ) + '\'';
// if the input field type is number and propertyValue is parse-able as a number
if (fieldType === 'number' && !isNaN(parseFloat(propertyValue))) {
// set expression without quotes surrounding propertyValue
expression = propertyName + '=' + propertyValue;
}
// if the field is a html select element
if (fieldType === 'select') {
// propertyValue will be blank because select elements don't have a value attribute
// instead, we need to use the value of the child option element that is selected
propertyValue = $(element.html()).filter(":selected").val();
// set expression to assume propertyValue is a string value
expression = propertyName + '=\'' + ( !!propertyValue ? propertyValue : '' ) + '\'';
}
// if the input field type is a radio button but its not checked (selected)
if (fieldType === 'radio' && !element.is(':checked')) {
// we need to reset the expression so a blank value is used
// doing this means that only the checked/selected radio button values get set on the model
expression = propertyName + '=\'\'';
}
// evaluate the expression, just as angular's ngInit does
scope.$eval(expression);
}
};
});
(it looks more complex than it actual is because I've left the comments in - strip those out and there's really nothing to it)
To use it, each field that I am using ng-model on, I also need to use the attribute data-lv-initialize-value-on-scope. You don't need to pass any value on the attribute, the directive gets everything it needs from the element and attr parameters
So far it caters with text, number, radio and select fields. The pages I'm working on don't have any checkboxes, but as and when I come across those I dare say I'll need to add some code for those.
It works, and I think I prefer this to using ng-init with a load of server-side to determine whether to set a value, what its data type should be, etc
The only downside I can see at the moment is that processing a radio button set might be inefficient. IE. if you have 10 radio buttons, each marked up with ng-model and data-lv-initialize-value-on-scope; all 10 will run the data-lv-initialize-value-on-scope directive and set a value on the scope. At least 9 of the iterations will set a blank value on the scope, and at most only 1 will set the actual value on the scope.
Hey-ho, it seems to work for now :). Hope this helps someone in the future
Nathan
I've got some JSON data- an Array of Fields containing Input Type (input, dropdown, radio, checkbox, etc.), Label and whether they are required or not.
I'm doing an ng-repeat through the array to build the form. I'm trying to understand what's the best way to build different kinds of inputs based on the Input Type value.
In normal programming, I would do a
foreach (var field in FormData){
if (field.inputType == "dropdown"){
//logic to build dropdown using jQuery, etc..
}
}
In AngularJS, I can't really do if thens within an ng-repeat="field in FormData". What's the proper way to dynamically build out these different kinds of elements while looping through an array?
This question is very similar:
How can I use Angular to output dynamic form fields?
Many thanks for any suggestions.
In my application, I did use an ng-switch (see the answer from the very similar question) in my ng-repeat to achieve something similar to this. The only problem with this is to link to the model. If you want to bind to a property name that is stored in a variable (if you json contains an id for the field), you won't be able to something like this :
<input type="text" ng-model="formdata.{{elem.id}}" />
I found that you can do this instead :
<input type="text" ng-model="formdata[elem.id]" />
I'm building an AngularJS app and I have ran into an issue. I have been playing with the framework for a while and I have yet to see documentation for something like this or any examples. I'm not sure which path to go down, Directive, Module, or something that I haven't heard of yet...
Problem:
Basically my app allows the user to add objects, we will say spans for this example, that have certain attribute's that are editable: height and an associated label. Rather than every span have its own dedicated input fields for height and label manipulation I would like to use one set of input fields that are able to control all iterations of our span object.
So my approx. working code is something like this:
<span ng-repeat="widget in chart.object">
<label>{{widget.label}}</label>
<span id="obj-js" class="obj" style="height:{{widget.amt}}px"></span>
</span>
<button ng-click="addObject()" class="add">ADD</button>
<input type="text" class="builder-input" ng-model="chart.object[0]['label']"/>
<input type="range" class="slider" ng-model="chart.object[0]['amt']"/>
The above code will let users add new objects, but the UI is obviously hardcoded to the first object in the array.
Desired Functionality:
When a user clicks on an object it updates the value of the input's ng-model to bind to the object clicked. So if "object_2" is clicked the input's ng-model updates to sync with the object_2's value. If the user clicks on "object_4" it updates the input's ng-model, you get the idea. Smart UI, essentially.
I've thought about writing a directive attribute called "sync" that could push the ng-model status to the bound UI. I've though about completely creating a new tag called <object> and construct these in the controller. And I've thought about using ng-click="someFn()" that updates the input fields. All of these are 'possibilities' that have their own pros and cons, but I thought before I either spin out on something or go down the wrong road I would ask the community.
Has anyone done this before (if so, examples)? If not, what would be the cleanest, AngularJS way to perform this? Cheers.
I don't think you need to use a custom directive specifically for this situation - although that may be helpful in your app once your controls are more involved.
Take as look at this possible solution, with a bit of formatting added:
http://jsfiddle.net/tLfYt/
I think the simplest way to solve this requires:
- Store 'selected' index in scope
- Bind ng-click to each repeated span, and use this to update the index.
From there, you can do exactly as you proposed: update the model on your inputs. This way of declarative thinking is something I love about Angular - your application can flow the way you would logically think about the problem.
In your controller:
$scope.selectedObjectIndex = null;
$scope.selectObject = function($index) {
$scope.selectedObjectIndex = $index;
}
In your ng-repeat:
<span ng-repeat="widget in chart.object" ng-click="selectObject($index)">
Your inputs:
<input type="text" class="builder-input" ng-model="chart.object[selectedObjectIndex]['label']"/>
<input type="range" class="slider" ng-model="chart.object[selectedObjectIndex]['amt']"/>
I would like to use AngularJS for some administration forms. It's very easy to bind view and model. I also like how you can add validation. But when I tried to prevent redundant code by introducing directives I hit a border. Could you please help me how I should structure code with AngularJS for this problem:
In my forms I have some compound fields. For example you can choose a country in a dropdown. Next to that dropdown you can enter a city in a textfield. When you choose another country the city name should be cleared. That's easy. Now I want autocompletion in the city textfield. When you enter a few characters you get suggestions for cities in the selected country. The autocompletion widget is the minor problem here, let's for simplicity say I would use JQueryUI for that.
I already managed to implement simple directives. My questions are:
1.) I like the functionality for validation in NgModelController. Can I somehow reuse this in my directive? It would be nice if I could add a "required" attribute to my directive. If it is set then all compound fields are required.
2.) How would I connect the directive with the surrounding model? For example I would like to edit a customer in an administration form and my "address" directive should display and edit the customer address.
3.) How would I connect the directive with my city lookup service? I need to give country and first typed letters of city to my service. Result is a list of city names that can be displayed in the autocompletion widget.
Here is the plunker that show you how to set require attribute.
Main idea is having required="{{isRequired}}" in the template and having isRequired as attribute for your directive.
template: '<input name="city" type="text" ng-model="city" placeholder="City" required="{{isRequired}}">'