Given rise to the mobile first approach, Angular 2 is an open source JavaScript framework that is widely being used for building web applications in JavaScript and HTML. This tutorial has been specifically designed for the software professionals who wish to learn the basics of the AngularJS 2 and its programming concepts in easy steps. To have a clear understanding of this tutorial, you should have a basic understanding of JavaScript and any text editor.
Angular 2- Overview
Angular 2 was basically introduced as a mobile-first framework that has been optimized for mobile performance. The framework’s latest version supports advanced gesture and touch events across varied mobile devices and tablets.
Reasons for using Angular 2
- Option of updating huge data sets with minimal memory overhead.
- When compared to Angular 1, Angular 2 is easier and some of its concept are simpler to understand.
- Speed up the initial load from server side rendering.
Striking features of Angular 2
- Angular 2 is much more faster and easy to use than Angular 1.
- Based on a cross-platform framework.
- This version of Angular is simplified than the previous one.
- Angular 2 mainly aims on mobile apps.
- Compatible with the latest version of browsers and also supports old browsers.
Benefits of Angular 2
- Making use of server side, it renders fast views on mobile.
- Everything will be related to the component based approach.
- It works in close coordination with ECMAScript and varied languages that are compiled to JavaScript.
- In case of any application that is a heavy load, Angular 2 keeps it fully UI responsive.
Angular 2 – Architecture
In this section, we will give a brief about the architectural style of Angular 2 framework, for implementation of user applications. The below diagram conveys the architecture of Angular 2.
The architecture of Angular 2 comes with the following modules:
- Template
- Component
- Data Binding
- Module
- Meta Data
- Directive
- Service
- Dependency Injection
Component
A component basically refers to a controller class with a template which mainly manages the application’s view and logic on a web page. It is a small code that can be utilized all over the application. Making use of the component inline styles, template inline styles and style urls, you can easily associate CSS styles to a component.
In order to register component, make use of @Component that can also be utilized for splitting the application into smaller parts. On every DOM element, there will be only one component.
Templates
Making use of the template that indicates the Angular as to how to display the component, you can easily define the component’s view. For example, the template given below shows how to display the name:
1 2 3 | <div> Your name is : {{name}} </div> |
In order to show the value, you can simply place the template expression within the interpolation braces.
Module
Featured by a block of code, the module component can be utilized for performing a sole task. The Angular apps are popularly known as modules and create your application using these modules. The most common building block of Angular 2 is a component class that can be easily exported from a module.
There might be some applications that will be having a component class name as AppComponent located in a file called app.component.ts. As written below, use the export statement to export component class from module:
1 | export class AppComponent { } |
Moreover, a module can be considered as a library for another module. For example, the angular2/core library that is the first Angular library module will be smoothly imported by another component.
Metadata
Metadata is an ultimate way of processing the class. For instance, if we have a single component known as MyComponent, it will be considered as a class till the time we do not notify the Angular that it’s a component. You can make use of the metadata to the class for telling Angular that MyComponent is a component. By utilizing the decorator, you can attach the metadata to TypeScript.
Data Binding
Data binding is basically a method of coordinating application data values by disclosing bindings among sources and target HTML elements. It merges the template parts with components parts where template HTML is bound with markup for connecting both sides. There are mainly four types of data binding namely property binding, interpolation, two-way binding event binding.
Service
Services are mainly the JavaScript functions that are accountable for performing any specific task. Angular services are inserted utilizing Dependency Injection mechanism. Service comprises function, feature or value that is required by the application. Commonly, services refer to a class that is capable of performing something exceptional like data service, logging service, message service or the configuration of application, etc.
Directive
The directive is basically a class showing the metadata. There are mainly three types of directives:
- Decorator Directive
- Component Directive
- Template Directive
Dependency Injection
Dependency injection generally refers to a design pattern passing any item as dependencies in varied components across the application. Apart from its needed dependencies, it also creates a new instance of class. The major benefit of Dependency Injection is that it can be stimulated in a framework and can be brought into use anywhere.
Pros of Angular 2
Angular 2 has been specifically designed keeping the future web requirements in mind. In order to make you feel more satisfied while choosing Angular 2, we would like to tell you that Google has already launched a project with this framework. Some of the major advantages of opting for Angular 2 are listed below:
Low decision fatigue
Being a framework, Angular 2 offers specifically more opinions and functionality out of the box. It helps you in getting started quickly without feeling intimidated by decisions. This enforced consistency enables new hires feel at home and make switching developers between teams more practical.
Mobile
Angular 2 version will mainly focus on the development of mobile apps. The rationale is that it’s simple to handle the desktop aspect of things once the challenges related to mobile have been addressed.
Modern
The main target of Angular 2.0 is the evergreen modern browsers that are automatically updated to the latest version. Building for these browsers basically means that several hacks and workarounds that make Angular tough to develop can be removed enabling the developers to focus on the code associated to their business domain.
Cons of Angular 2
Though, there are several benefits of Angular 2, but there are some major cons of it. Here, we have listed some of the major drawbacks of Angular 2.
Shaky Foundation
Built on experimental language features, Angular 2 framework claims to be more secure than its dependency and the language built on. But, this is absolutely false. Angular 2 should not call itself stable as its core dependencies have not landed.
TypeScript
Without having the knowledge of statically typed or OOP languages, TypeScript is very complicated to manage. You cannot run it directly without a compile stage. Moreover, TypeScript is not able to fix what was broken in JS.
Poor Performance
Angular 2 seems to be exceptionally heavy. Angular 2 app seems to struggle with the most basic of tasks taking several seconds to render and reload. Though, this may sound small but remember that any small change to the source code can result in the reload so this might be something that needs to be done hundred of times per day.
Future Scope
Angular 2 is the ultimate platform successor to Google’s Angular 1 web application framework that is designed for building complex applications in browsers and beyond. Angular 2 open doors for other programs as well that some developers would have never experienced with. One of the major reasons that the Angular 2 team built it this way was to be tool-able. Angular 2 enables the developers to expand what they are doing and build on top of it.
Conclusion
This tutorial has been prepared keeping all the essential factors in mind. We have tried to explain everything about Angular 2 in detail and hope that it helps you in a great way. There are myriad of benefits that this effective framework possesses and transmit the same to the web applications made under it.
