Get Familiar with Spry in Dreamweaver CS4

Are you new to Adobe Dreamweaver CS4 and would like to know what Spry is all about? This excerpt from Dreamweaver CS4: The Missing Manual will get you familiar with Spry and its capabilities.

What exactly is Spry? Spry isn't just a Dreamweaver tool; it's a technology developed by Adobe, and distributed freely and independently on the Adobe Labs Web site (http://labs.adobe.co...hnologies/spry/).

It's officially called the "Spry framework for Ajax" and it's a collection of Javascript programs that let you, the Web designer, offer sophisticated control of a Web page to your visitors through widgets, effects, and data sets. A widget is an interface element like a menu bar, form validation message, or set of tabbed panels that generally makes a site easier to use. For example, the Spry Menu Bar adds a lot of links to a compact navigation bar, so you can easily find your way around a Web site.

An effect is a visual treat that doesn't necessarily improve how a Web page works, but adds cool eye candy. You can use a Spry effect to fade page elements in and out of view (effects are discussed in the next chapter). Finally, a Spry data set is a data presentation format that's more interactive than a standard HTML table. Imagine you have a table listing products your company sells. Each product is presented in its own row with columns for product name, price, and availability. A visitor can sort a Spry data table by any of those columns, simply by clicking the name of a column. And it all happens without the browser ever having to reload a Web page.

In addition, a Spry data set can suck down the contents of an XML file or even just a garden-variety HTML table, and then update a Web page with the file's content. But because XML isn't used by all Web designers, Dreamweaver CS4 lets you put data into a common HTML table and use that as the basis for an interactive presentation of data. This Spry data set tango is the "Ajax" part of the "Spry framework for Ajax." Ajax is a term coined in 2005 to describe a timesaving system for transferring information from a Web server to a Web page (and vice versa). The revolutionary advantage of Ajax, as highlighted in the Google Maps example, is that it lets a page's contents change quickly without having to reload a new page from the server.