Section 4.4. Problems Created by the New Development Paradigm

4.4. Problems Created by the New Development Paradigm

Most of the problems with AJAX are caused by its added complexity. Because the communication with the server happens in an opaque manner, it is easy to lose error messages or learn that there is an error without also getting all the additional details you relied on before using AJAX. These aspects force you to rely on server-side logging, which is something most casual developers seldom do. The complexity is also increased by the more frequent use of JavaScript. No matter how comfortable you are with it, you still have two main development languages (JavaScript and whatever you run on your server) and cross-browser compatibility to worry about.

There are a number of ways to manage this added complexity. One of the simplest solutions is to create test constructs that allow you to test your server components without connecting them to the front end. The additional complexity created by adding a new language is harder to manage, but it can be done, either by using developers with lots of JavaScript experience or by limiting the scope of your JavaScript development to only those features that have the biggest payoff.

Developing with AJAX can also create new usability and design problems. As you add more interactive features to a Web site, it moves further away from the model your users have used. One way to avoid this is to make the site look and feel more like an application; this gives the users a clue that the site will be working like an application and not like the Web site to which they are accustomed. However, in many cases, there is no easy way to mimic native applications, especially in areas where no similar native application exists. In these cases, you'll have to use other cues to create appropriate usability expectations from your users. Following the usability guidelines provided in Chapter 6, "Usability Guidelines," can help solve many of these basic usability problems.

AJAX can also cause problems because it is new and because it's a prime candidate for overuse. AJAX is powerful and can create some great solutions, but that doesn't mean it can solve every problem. For instance, you may have a general usability problem that can be solved only by updating the user interface. Throwing AJAX at the problem isn't going to solve anything. In other words, keep in mind that AJAX isn't a magic bullet; to use it effectively, you must keep your goals and overall usability in mind when adding it to an application's design.