Introduction to AngularJS Framework (with Key Concepts)

AngularJS basic concepts help you turn static HTML into dynamic, testable application. By extending HTML with directive, data binding, and dependency injection, AngularJS streamline app construction.

Use these fundamentals to make scalable, maintainable, and cross-browser compatible web apps faster.

This article explains what AngularJS is, its nucleus edifice blocks, how to set up a basic app, and how to essay AngularJS efficaciously.

What is AngularJS Framework?

AngularJS fabric is used for creating with a structural architecture. This model enable using HTML as the guide words and facilitates the extension of HTML & # 8217; s syntax to express application components clearly and concisely.

Features such as Data binding and dependence injection reduce the codification required. The unharmed summons occurs solely within the browser, rendering it a suitable complement to any server technology.

With this JavaScript MVC framework, you can effortlessly craft dynamic web applications bundle with features and experience the multitude of benefits it offers, empowering developers to make web applications that are both user-friendly and engaging and captivating.

Benefits of using AngularJS Framework

• No prerequisite involve: AngularJS is designed to be compatible with HTML, CSS, and JavaScript. Learning a new scripting language is unnecessary. Also, HTML, CSS, and JavaScript are relatively simple to pick up, even if you don & # 8217; t cognise them already.
• Simple to expand: because of several built-in feature, HTML & # 8217; s functionality may be increased by twin a particular behavior. It is customized since one may add their own directive to it.
• Splendid MVC: To apply the Model-View-Controller (MVC) architecture, many fabric demand the code to be broken up into freestanding MVC components (Model, View, and Controller). The procedure is fully automatize in Angular. Angular helps programmers relieve clip by organizing their code.
• Simple for Testing: Angular is written in the dynamically typed JavaScript speech. The expressive potential of angular is vast. However, Angular does not come with a compiler. Therefore, a solid tryout code for it must be written. Unit screen will be lots simpler because it has a dependency injectant built flop in. Angular is compatible with both unit tryout and scheme tests.
• TypeScript, a Microsoft-managed scheduling lyric, is the foundation for the Angular framework. Because it serves as Angular & # 8217; s bag language and is powerfully typecast, it helps developer avoid mussy code. A plan with such pristine code should run smoothly and efficiently.

Example of AngularJS

& lt;! DOCTYPE html & gt; & lt; html & gt; & lt; script src= '' https: //ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js '' & gt; & lt; /script & gt; & lt; body ng-app= '' BrowserstackApp '' ng-controller= '' myNoteCtrl '' & gt; & lt; h2 & gt; BrowserStackNote & lt; /h2 & gt; & lt; textarea ng-model= '' message '' cols= '' 40 '' rows= '' 10 '' & gt; & lt; /textarea & gt; & lt; p & gt; & lt; button ng-click= '' save () '' & gt; Save & lt; /button & gt; & lt; button ng-click= '' clear () '' & gt; Clear & lt; /button & gt; & lt; /p & gt; & lt; p & gt; Number of fiber leave: & lt; span ng-bind= '' left () '' & gt; & lt; /span & gt; & lt; /p & gt; & lt; script & gt; var app = angular.module (`` myNoteApp '', []); app.controller (`` myNoteCtrl '', function ($ ambit) {$ scope.message = `` ''; $ scope.left = function () {return 100 - $ scope.message.length;}; $ scope.clear = function () {$ scope.message = `` '';}; $ scope.save = function () {alert (`` Note Saved '');};}); & lt; /script & gt; & lt; /body & gt; & lt; /html & gt;

General Features of Angular JS Framework

AngularJS has the follow general feature:

• Angularjs is a proficient framework for evolve Rich Internet Applications (RIA).
• It enables developers to make client-side coating using JavaScript in a structured Model-View-Controller (MVC) practice.
• AngularJS applications are compatible with multiple web browser. AngularJS automatically manages cross-browser JavaScript codification.
• It is a wide used open-source and has a global developer community.
• It is a model for developing web applications that are scalable, high-performing, and easily maintainable.

Key Concepts of AngularJS Framework

1. Data dressing

Data binding controls page elements such as headings, text, and images. It bridges the gap between an app & # 8217; s user interface and underlying information. It is potential to make change on the model side and have them straightaway mirrored on the vista side, and vice versa. This is done so fleetly to ensure that the view and the model part are invariably updated.

• Adding a few lines of AngularJS codification may connect the model and view portion.
• To do this, a concept known as directive is used.
• This allows you to link the value of a header or stimulant field (a web ingredient) to an HTML element. ng-bind is one of the directive that may be use to do this.

& lt; div ng-app= '' BrowserStackApp '' ng-controller= '' myCtrl '' & gt; & lt; h3 ng-bind= '' heading '' & gt; & lt; /h3 & gt; & lt; /div & gt; & lt; handwriting & gt; var app = angular.module (demoApp, []); app.controller ('myCtrl ', function ($ scope) {$ scope.heading = `` Explaining Data binding!! ``;}); & lt; /script & gt;

As a result, you can link the datum, which is the text & # 8220; Explaining Data Binding!! & # 8221; (model part), to an H3 tag (view component).

2. Directives

Directives are intended to be functions that the Angular compiler trial when they are bump in the DOM to enhance the power of HTML with new syntax. Directives have a name and maybe preset or custom-defined, grant them to be named anyplace. Its usage is controlled by the preset directive & # 8211; dimension, gossip, element, or class.

Directives in Angular can be put into these categories:

• Component Directive
• Structural Directive
• Attribute directive

3. Dependency Injection

You may consider of Dependency Injection in AngularJS as the package design figure that delimitate how software components rely on one another. Factory, value, constant, service, and supplier are some of the injectable dependencies in AngularJS.

4. Modules

A faculty may be considered a container for your app & # 8217; s many ingredient, such as controllers, services, filter, directive, etc. Most applications contain a principal method that creates and connects all the application & # 8217; s constituent.

Apps built using AngularJS lack a principal method. Instead, faculty define declaratively how to bootstrap an application. This scheme has respective benefits:

• The declarative approach is simpler to savvy.
• Code may be put into modules that are reused.
• Because modules detain the execution, they can be loaded in any order (or even concurrently).
• Unit tests are quick since they involve to load the necessary modules.
• Modules may be used in end-to-end tests to override shape.

5. Scope

• In AngularJS framework, the scope plays a vital role. It function as a span between the Controller and the View (HTML).
• Every Angular directive scope target created via a controller or any other directive or service inherits from the parent setting. Each directive has its unique angular scope.
• Accessing variables and methods inside a template or reference office is reach using directive within the telescope.
• Never will you see a guiding create its telescope. It needs to be incisively defined.
• Directives use their parent scope by default (the scope from which it is called).

6. Controllers

AngularJS controllers deal the data flowing of an AngularJS application. The ng-controller directive is used to delimit a control. A controller is a JavaScript target with attributes, place, and method. Each controller receives the parameter $ scope, which mention to the coating or module it is to control.

Setting up an AngularJS Environment

Downloading, Configuring, & amp; Creating an AngularJS Project

To set up an AngularJS development environment, you require the pursuit:

• AngularJS Library
• Editor/IDE
• Browser
• Web waiter

Go to angularjs.org and click the download choice to get the AngularJS library. This will launch the window demo below.

Click the download push in the window after choosing the necessary variation from the tilt.

The AngularJS library may be include via the CDN at the next URL:

https: //ajax.googleapis.com/ajax/libs/angularjs/1.3.16/angular.min.js

AngularJS is finally composed of JavaScript and HTML codification. As a result, you are free to install any reputable editor or IDE.

• Sublime Text
• Aptana Studio 3
• Ultra Edit
• Eclipse
• Visual Studio

Web server: Use any topically available web waiter, such as IIS, Apache, etc., for development purposes.

Browser:Any browser you care may be installed since AngularJS provide cross-browser compatibility. The use of Google Chrome is advised for creating application, withal.

Pro tip: Tools like SUSA can handle this autonomously — upload your app and get results without writing a single test script.

Illustration

Let & # 8217; s now make a simple example using the AngularJS fabric. Let & # 8217; s make the HTML file userFirstExample.html, which is seen below.

& lt;! doctype html & gt; & lt; html & gt; & lt; head & gt; & lt; script src = `` https: //ajax.googleapis.com/ajax/libs/angularjs/1.5.2/angular.min.js '' & gt; & lt; /script & gt; & lt; /head & gt; & lt; body ng-app = `` browserstackApp '' & gt; & lt; div ng-controller = `` HelloMyController '' & gt; & lt; h2 & gt; Welcome {{helloTo.title}} to the world of BrowserStack! & lt; /h2 & gt; & lt; /div & gt; & lt; handwriting & gt; angular.module (`` browserstackApp '', []) .controller (`` HelloMyController '', map ($ scope) {$ scope.helloTo = {}; $ scope.helloTo.title = `` AngularJS '';}); & lt; /script & gt; & lt; /body & gt; & lt; /html & gt;

To use AngularJS, you add its JavaScript file to the HTML page.

& lt; head & gt; & lt; script src = `` https: //ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js '' & gt; & lt; /script & gt; & lt; /head & gt;

Next, which section of HTML house the AngularJS application must be know. This may be fulfil by adding the ng-app property to the AngularJS app & # 8217; s root HTML component. As seen below, you may either add it to the body ingredient or the html element.

& lt; body ng-app = `` browserstackApp '' & gt; & lt; /body & gt;

View

& lt; div ng-controller = `` HelloMyController '' & gt; & lt; h2 & gt; Welcome {{helloTo.title}} to the world of BrowserStack! & lt; /h2 & gt; & lt; /div & gt;

The ng-controller directing instructs AngularJS on the controller to use with this prospect. helloTo.title instructs AngularJS to insert the model value helloTo.title in HTML at this localization.

Controller

& lt; script & gt; angular.module (`` browserstackApp '', []) .controller (`` HelloMyController '', function ($ scope) {$ scope.helloTo = {}; $ scope.helloTo.title = `` AngularJS '';}); & lt; /script & gt;

This code append a HelloController controller mapping to the browserstackApp angular faculty. Controller mapping receive the $ setting parameter model. In the helloTo JavaScript object that is added by the accountant function, a title field is added.

Execution: Save the above code as userFirstExample.html and launch it in your preferent web browser. You will observe the undermentioned result:

Welcome AngularJS to the macrocosm of BrowserStack!

What occurs as soon as the page charge in the browser? Let & # 8217; s find out

• The browser loads an HTML page, which it then analyses.
• The Angular global object is generate after loading the AngularJS JavaScript script.
• It scat the JavaScript that registers controller functions.
• After that, AngularJS explore through the HTML for AngularJS application and views.
• Once the prospect has been found, it links it to the relevant restrainer function.
• After that, AngularJS do the controller operations.
• The data from the model the restrainer has populated is then used to display the aspect. The page is now ready.

Components of an AngularJS Application

While it & # 8217; s true that AngularJS is a robust front-end model, you won & # 8217; t be able to direct vantage of all of its features until you implement components. An Angular constituent is a self-contained code that can be reused and updated independently. A basic definition of a component is a method or function that include both the controller code and HTML tags necessary to make a single UI element.

The last result of your component should be to render the simple piece of HTML:

& lt; span & gt; Hello World! & lt; /span & gt;

The syntax for creating a new component is simple. Declare the gens of your component and send it along with a config target that details its expected behaviour. Here, it will render some rattling elementary HTML:

angular.module (`` browserstackApp '', []) .component (`` helloWorld '', {template: 'Hello World! '});

Then, to integrate that part into our code, you need only…

& lt; div ng-app= '' browserstackApp '' & gt; & lt; hello-world & gt; & lt; /hello-world & gt; & lt; /div & gt;

Working with AngularJS Directives

In AngularJS, the majority of directives have an ng prefix. ng is short for & # 8220; angular & # 8221;. However, ng is not always the required prefix. You may alternatively prefix with x- or data-.

Steps for Adding Directives

1. The .directive function is utilize to generate new directives. You must create an HTML element with the same tag name as the new directive to use it.
2. A directive must be call using camel case, such as myNewDirective, but you must use the gens separated with – such as my-new-directive.

& lt; body ng-app= '' browserstackApp '' & gt; & lt; my-new-directive & gt; & lt; /my-new-directive & gt; & lt; playscript & gt; var app = angular.module (`` browserstackApp '', []); App.directive (`` myNewDirective '', function () {render {guide: `` & lt; h1 & gt; Made by a directive! & lt; /h1 & gt; ''};}); & lt; /script & gt; & lt; /body & gt;

You can use different ways to call a directive. That is:

• Element name
• Attribute
• Class
• Comment

It will result in the same result using any of the methods above.

& lt; script & gt; var app = angular.module (`` browserstackApp '', []); App.directive (`` myNewDirective '', function () {return {restrict: `` C '' template: `` & lt; h1 & gt; Made by a directive! & lt; /h1 & gt; ''};}); & lt; /script & gt;

Attributes, element names, remark, and CSS course are all examples of AngularJS directives. They apprise AngularJS to modify the DOM factor and its children or to add a sure behavior to it.

Simply put, a directive tells AngularJS to handle a yield factor in a sure way. A reusable component may likewise be built with the help of AngularJS directives.

Controllers in AngularJS

The method for employ the ng-controller directive in an angularjs application to delimit a controller and admittance datum is as follows.

& lt; script type= '' text/javascript '' & gt; var app = angular.module ('angularctrlapp ', []); app.controller ('angularctrl ', office ($ scope) {$ scope.msg = 'Welcome to Browserstack.com ';}); & lt; /script & gt; & lt; div ng-app= '' angularctrlapp '' ng-controller= '' angularctrl '' & gt; {{msg}} & lt; /div & gt;

If you look at the code above, you & # 8217; ll see that ng-app serves as the start point for an angularJS coating, and the elements within a div will be capable to use angularJS functionality. Check out this Angularjsng-app directivefor additional information about ng-app.

Typically, you use an AngularJS module to create the controller. Because angularjs controllers are call utilize the $ scope objective, hither you initialized the $ scope objective in the restrainer map.

Here is an exemplar of an AngularJS coating using a comptroller:

& lt;! DOCTYPE html & gt; & lt; html xmlns= '' http: //www.w3.org/1999/xhtml '' & gt; & lt; head & gt; & lt; title & gt; AngularJs Controllers Example & lt; /title & gt; & lt; script src= '' http: //ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js '' & gt; & lt; /script & gt; & lt; script type= '' text/javascript '' & gt; var app = angular.module ('angularctrlapp ', []); app.controller ('angularctrl ', function ($ reach) {$ scope.fname = `` Welcome to ''; $ scope.lname = `` Browserstack '';}); & lt; /script & gt; & lt; /head & gt; & lt; body & gt; & lt; div ng-app= '' angularctrlapp '' ng-controller= '' angularctrl '' & gt; First Name: {{fname}} & lt; br / & gt; Terminal Name: {{lname}} & lt; br / & gt; Full Name: & lt; b & gt; {{fname + '' `` + lname}} & lt; /b & gt; & lt; /div & gt; & lt; /body & gt; & lt; /html & gt;

The $ scope variables fname and lname will get their values from the controller if the example above is action, and you may display them in the coating. The result of expend controllers in angularjs applications is as follows:

First Name: welcome to Last Name: Tutlane Full Name: welcome to Tutlane

Services in AngularJS

Services in AngularJS are singleton objects that are instantiated only once per covering. Services are apply to organise and portion codification throughout an application. It implies that services might be crucial in carrying out just certain tasks. You may construct model information employ $ background and attach it to the aspect; data manipulation is not its duty.

• A few helpful functions are include in service target and may be called from comptroller, directives, filter, etc.
• Numerous built-in services, include $ https, $ route, $ window, $ position, etc., are included with AngularJS.
• You may also acquire your own service using AngularJS by registering the service.
• The AngularJS compiler may refer to and load a service as a addiction for runtime usage after it has been registered.

There are different approaches to building a service using AngularJS:

Syntax1: Service

var faculty = angular.module ('browserstackApp ', []); module.service ('customerService ', function () {this.customers = ['Jimi ', 'Tom ', 'Jake '];});

Syntax2: Factory

var module = angular.module ('browserstackApp ', []); module.factory ('customerService ', function () {var cust = {}; cust.customers = ['Arvind ', 'Tom ', 'Felix ']; return cust;});

Example: 

& lt; html & gt; & lt; head & gt; & lt; title & gt; My firstly AngularJS Service code & lt; /title & gt; & lt; Script SRC= '' https: //ajax.googleapis.com/ajax/libs/angularjs/1.2.13/angular.js '' & gt; & lt; /Script & gt; & lt; Script & gt; //Defining Services Using Service var app = angular.module ('app ', []); app.service ('MathService ', part () {this.add = function (a, b) {regress a + b}; this.subtract = function (a, b) {render a - b}; this.multiply = role (a, b) {regress a * b}; this.divide = function (a, b) {regress a / b};}); app.service ('CalculatorService ', function (MathService) {this.square = mapping (a) {return MathService.multiply (a, a);}; this.cube = function (a) {homecoming MathService.multiply (a, MathService.multiply (a, a));};}); app.controller ('CalculatorController ', mapping ($ scope, CalculatorService) {$ scope.doSquare = function () {$ scope.answer = CalculatorService.square ($ scope.number);} $ scope.doCube = function () {$ scope.answer = CalculatorService.cube ($ scope.number);}}); & lt; /Script & gt; & lt; /head & gt; & lt; body & gt; & lt; div ng-app= '' app '' & gt; & lt; div ng-controller= '' CalculatorController '' & gt; Enter a routine: & lt; input ng-model= '' number '' type= '' number '' & gt; & lt; button ng-click= '' doSquare () '' & gt; X & lt; sup & gt; 2 & lt; /sup & gt; & lt; /button & gt; & lt; button ng-click= '' doCube () '' & gt; X & lt; sup & gt; 3 & lt; /sup & gt; & lt; /button & gt; & lt; div & gt; Answer: {{respond}} & lt; /div & gt; & lt; /div & gt; & lt; /div & gt; & lt; /div & gt; & lt; /body & gt; & lt; /html & gt;

Let & # 8217; s improve the utility of our factor right now. Data is typically loaded by a service and so delivered to the components that need it in a single-page coating that consists of many modules.

Here & # 8217; s how you may put it into practice apply a argument for naming your component:

& lt; div ng-app= '' myApp '' & gt; & lt; hello-world name= '' 'Arvind ' '' & gt; & lt; /hello-world & gt; & lt; /div & gt;

By giving your component bindings, you may do this. The name of the attribute that will be added to your component and the sort of binding you will use is essentially define hither. Four distinct kinds of bindings exist:

• = point that two-way data dressing is be use. In other language, if you update that variable in your portion scope, the parent scope will also reflect the change;
• & lt; is for one-way bindings, When you want to say a value from a parent scope and not update it, you use one-way bindings;
• @ is for draw parameters;
• If your component needs to output something to its parent scope, use the callback symbol (& amp;)

In your scenario, you should use a simple string so that your component resemble the followers:

angular.module (`` browserstackApp '', []) .component (`` helloWorld '', {template: 'Hello {{$ ctrl.name}}! ', dressing: {name: ' @ '}});

The local scope of your component, which is by default connected to a controller call $ ctrl, will get bandaging added to it. Due to this, the HTML template uses the phrase & # 8220; $ ctrl.name & # 8221; to get the value to show.

How to prove an AngularJS web application on BrowserStack?

It would be best if you had a unbendable grasp of these core thought before delving into testing individual constituent inside an Angular application, and you now do. When doing automate tests in an AngularJS surroundings, read this

To test an AngularJS web coating on BrowserStack, follow these stairs:

1. Choose the browsers and device to test your AngularJS web coating using BrowserStack & # 8217; s browser matrix.
2. For Automated testing, you can either use the feature or use a Selenium or WebDriver script. If using Selenium or WebDriver script, ensure you receive installed the necessary libraries and addiction, and modify your script to include the BrowserStack credentials.
3. Run your tests and critique the results to ensure your AngularJS web coating works correctly on all browser and devices.

Closing Notes

One of the main aims of AngularJS from its first release has been to furnish a framework for germinate unit-testable code. All AngularJS components (controllers, directive, services, and filters) are built using the dependency injector, an elegant and complex component of AngularJS. This makes it potential to easy stub out your code & # 8217; s dependencies as needed for your tests.

The architectural and testing tool of AngularJS also integrate well with assorted free and open-source JavaScript physique and workflow tools, including Gulp and Grunt. With these instrument, you can fabricate unscathed new apps from the offset, perform your tests cleanly, and include tools like code coverage and linting into your test execution.

FAQs

1. What is AngularJS used for?

AngularJS offers the power to convert static HTML into dynamic HTML. This framework extends HTML & # 8217; s capabilities with built-in attributes and components and facilitates the creation of custom attributes using basic JavaScript.

2. What is the difference between AngularJS and JavaScript?

• Javascript is an object-oriented programming languagefor applications, particularly for mobile and dynamic online platform. Its core is the dynamical typewriting concept.
• AngularJS is an open-source framework that can be utilize to build dynamic web application and tumid single-page web undertaking. Angular JS is an coating development model based on the MVC architectural paradigm.

3. Is AngularJS a language?

Angular is a framework and platform for creating HTML and TypeScript single-page client applications.

4. Which fabric is AngularJS?

AngularJS is a fabric built in JavaScript. It can be added habituate the & lt; playscript & gt; tag on an HTML page. AngularJS augments HTML attributes with Directives and binds HTML data with Expressions.

Related Guides