Williamson - Learning AngularJS

by Ken Williamson

Copyright 2015 Ken Williamson. All rights reserved.

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The world of software development has changed drastically over the last few decades. Many software methodologies and concepts that were considered cutting edge 20 or so years ago are now common practice in the field of software development, and have been for years. One example is the World Wide Web and the use of web browsers to deliver software to users. In 1993, the concept of delivering software over the Internet that could then run in a web browser on any machine running on any operating system was considered bleeding edge. But as any computer user knows, that practice has been commonplace for years now.

When JavaScript client-side web application frameworks like AngularJS, Backbone.js, and Ember.js first appeared, they were considered too cutting edge for most serious software projects. As they matured, however, software architects and developers saw great potential in these frameworks. Applications built with JavaScript client-side frameworks exist and run entirely on the users hardware, much like conventional thick-client applications. Applications written using these frameworks are much faster than conventional web applications and provide a much better user experience.

Over the last couple of years, JavaScript client-side frameworks have made great strides in functionality and reliability, and they are now heavily used to build mobile HTML5 applications. But mobile applications are only the starting point. These frameworks now have the potential to radically change the way we build modern web application software. Of all the JavaScript frameworks available, AngularJS, backed by Google, is the one that shines the brightest.

AngularJS has many advantages over other JavaScript client-side frameworks. AngularJS uses the MVC design pattern and embraces that pattern completely. The model, view, and controller are all clearly defined in AngularJS and serve to greatly simplify the development process. With AngularJS, developers can build applications that have a clear separation between their functional layers.

One of the greatest advantages of AngularJS over other JavaScript client-side frameworks is the unique way in which it lets developers interact with RESTful web services. AngularJSs resource object lets developers interact with REST services like standard objects. The complexity of REST services can be greatly simplified using this approach: with only a few lines of code, you can create an AngularJS service that interacts with multiple backend REST services. Those services can then be used throughout your application, reducing the total number of lines of code.

In fact, one of the biggest advantages of AngularJS over other client-side frameworks is its concept of services. AngularJS services help to greatly simplify an application by compartmentalizing client-side logic into single units of code. Those single units, called services, can then be used repeatedly throughout an application. AngularJS services prove especially powerful when youre building large enterprise applications with many lines of code and much complexity. Complex logic can be written only once inside an AngularJS service and then used wherever needed. That alone makes AngularJS the best choice for your next JavaScript project.

Thanks to this use of services and its all-inclusive design, AngularJS helps developers write less code, thereby greatly reducing application complexity. The simplicity of AngularJS makes it easy to learn and easy to use. Any time spent learning AngularJS is time well spent. Any time spent developing AngularJS applications is time spent turning a cutting-edge technology into a commonplace technology. In this book I strive to help you do both, encouraging design concepts and practices that will help you build better AngularJS applications.