Review : Programming Atlas

Title: Programming Atlas  Author: Christian Wenz  Publisher: O'Reilly Pages: 382 Rating: 3 of 5

Popularity of AJAX is growing day by day. Microsoft's AJAX implementation for ASP.NET is a great way to develop AJAX enabled web sites will minimum efforts. Microsoft AJAX framework recently reached RC stage and we can hope that it will be available soon. If you are a developer always keeping yourself updated with latest technologies then it is the right time to learn ASP.NET AJAX framework. To that end Programming Atlas by O'Reilly can be your nice pick.

Programming Atlas is possibly the only book (at least that I came across) that is closer to the RC version. Of course there are some things that you much change while running the book examples but that is expected for any book talking technology in beta stages. Most important change being separation of client controls in Microsoft.Web.Preview assembly. The concepts still remain the same. I hope that as the ASP.NET AJAX is approaching the release date the author and publisher will release an updated edition.

The book consists of 16 chapters. Out of the 16 chapters 12 are dedicated exclusively to ASP.NET AJAX. The remaining chapters deal with allied topics such as JavaScript, XmlHttp and JSON.

The book begins with an introduction to ASP.NET, Atlas (now ASP.NET AJAX) and Ajax. It familiarizes you with ScriptManager and builds a simple Atlas application.

Though Atlas provides many things "out of the box" sound understanding of JavaScript is still a nice skill set for any developer. The Chapter 2 gives you basic concepts of JavaScript and DOM. I feel this chapter is inadequate. A sound introduction along with some real world examples would have been a nice addition.

Chapter 3 explains XML HTTP and XML DOM. The chapter shows some basic examples of using XML HTTP object directly without any framework. You get an idea of asynchronous communication and role of XML HTTP through these examples. Some more examples of using DOM follow. They show you how to create HTML elements on the fly using DOM APIs.

From Chapter 4 onwards real Atlas programming begins. Chapter 4 explains Atlas client side controls in detail. You should be bit careful while coding examples from this chapter as Microsoft has moves the client controls in the Microsoft.Web.Preview assembly. So, you need to change the control namespaces accordingly. However, this chapter gives a good understanding of the Atlas client controls.

Most of the applications today deal  with data in one form or the other. Chapter 5 deals with data binding and validation. In this chapter you are introduced with XML script - a new script based declarative way for implementing data binding and event handling. Understanding of XML script is very important because it can save you lot of coding.

Chapter 6 is about components and behaviors. In this chapter you learn another way of handling events in the form of behaviors. Behaviors can save you lot of coding. They also simplify your job. Behaviors are always bound to a particular elements on your page whereas components need not be. The chapter discusses Click behavior and Popup component.

Chapter 7 discusses another interesting feature - animations. AJAX is becoming popular because it provides rich user experience. Animations, if used wisely, can come as a handy way to enrich your applications. The chapter explains animation effects such as fading and moving. Some additional and bit complex examples would have been a nice addition.

One good feature of Atlas is that it makes overall JavaScript richer. Chapter 8 shows how Atlas does that. You learn things such as inheritance, custom namespaces and other OO features. Remember these are client side OO features and not the C# or VB.NET features that you are familiar with. The chapter also explains some classes that are counter parts of .NET classes e.g. StringBuilder

Chapter 9 and 10 are all about consuming server data. You learn to consume Web Services from Atlas client side script. You also learn to use client side ListView control for displaying data returned from web methods. It also explains creating custom data sources and consuming external web services via web service bridge. These two chapters are very important because most of the times your data resides on the server. They are must read for any atlas developer.

Atlas makes it possible for you to add features such as drag and drop to ASP.NET server controls. This is the topic of Chapter 11. You learn to implement drag and drop and autocomplete features via Atlas control extenders. This chapter also explains UpdatePanel control which makes any server control AJAX enabled. In my opinion this topic should have been given more weightage with real world examples and do's and don'ts.

Chapter 12 shows you how to use Virtual Earth APIs. Chapter 13 shows an important aspect - working with web parts via Atlas. Since web parts play important role in personalization and user experience it is important to learn integration between Atlas and web parts. On the same lines it would have been nice to show integration between ASP.NET services such as membership and profiles.

Chapter 14 discusses Atlas Control Toolkit. Atlas control toolkit is a set of handy server controls that can simplify your job. e.g. Popup menu, Cascading drop down and Modal popup window. Though this chapter explains basics of these controls it doesn't give sound examples. Considering that Atlas Control Toolkit is going to become developer's favorite author should have included a detailed explanation and working of major controls.

Chapter 15 and 16 explain the use of Atlas with other technologies such as PHP and other AJAX tools such as Ajax .NET. These two chapters, though nice, are not directly related to ASP.NET and Atlas. I feel they are not much  useful to ASP.NET developers using Atlas.

Overall the book gives a very good introduction of this emerging technology. However, one drawback is that the version of Atlas used in the book is already outdated (The same problem can be seen with most of the other books). However, I am sure that they will release an updated version soon. The background information is still applicable. If you are looking for a sound yet quick understanding of Atlas you can certainly pick this book up.