AJAX for Joomla components

AJAX (which stands for Asynchronous JavaScript and XML) combines a powerful set of technologies for Web 2.0 sites. Using Ajax technology, you can make the user experience far more interactive than previous Web site implementations. In the past, changes to parameters or the selection of buttons on a Web page required the changes be sent back to the Web server for an update. The browser would have to wait for the entire modified page to be returned to display the revisions. Using that process, user interaction with a Web application was fairly clunky.

The first piece in the application is the Joomla component. A Joomla component can be directly queried so that it will provide output without any menus or the other user-interface items that usually surround it. Therefore, the component only must output a single line of text that the Ajax application will display. If the component is working properly, you will see the single line of text output by the component in the browser window. If you view the source of the window, the HTML code will show nothing except the exact text. By setting the format to raw, Joomla executes the specified component and returns only the output that it has generated. This method is exactly how the Ajax Web page requests information for display.

The Ajax Web page will call upon the component for the product information and then display this information in an alert window. This file will be more complicated because it includes three steps of the Ajax process: user interaction, information request, and information receive/display. The user interaction consists of a simple on MouseOver event that will be constructed to execute a JavaScript function. In this case, the event will be set up to activate when the user places the mouse cursor within the area specified by a paragraph or

tag. With a basic implementation complete, you could now create a more powerful example. Most real-world Ajax solutions require a combination of dynamic content generation and Ajax interactive technology to allow more information to be retrieved from the same system.

Given the exciting nature of the Ajax technology, it is easy for developers to overlook the shortcomings. Aside from the complexity that Ajax can add to a Web development project, there are a number of very real problems that will be encountered as Ajax use grows: Ajax Search Engine Optimized (SEO) invisibility, Information harvesting, and possible security risks. Since Ajax has begun to spread like wildfire, entire sites are using Ajax for everything from menu display to core information presentation. While it is easy to get caught up in the excitement of a new technology, it is important to recognize where that technology can be best applied. However, all of the content that is displayed by the Ajax widgets is invisible to search engines. A search engine spider will not execute the code contained in an Ajax JavaScript link.

Many software products like AJAX Listing, AJAX recommend, AJX Register and AJAX Scroller for Joomla components.