On 11/15/05, Eugene Lazutkin <[EMAIL PROTECTED]> wrote: > Now I am confused. AJAX stands for Asynchronous JavaScript And XML. But > "AJAX effects" == visual effects?
Many so-called "AJAX libraries" are as heavy on the "visual DHTML effects for use with AJAX" as on the actual meat of "AJAX" itself. This is because, in response to the usability problem of how to draw a user's notice to a change in the page, many developers have resorted to attention-getting visual DHTML (where by "DHTML" I mean client-side scripting intended to alter the DOM and or styling of an already-rendered document) effects; many so-called "AJAX libraries" and "AJAX toolkits", as a result, bundle common DHTML visual effects as components and provide ways in which they can be easily called singly or in combination. For example, Rails includes an "AJAX library" called Prototype; this library provides "AJAX" functionality in that it delivers a facility for making asynchronous server calls from the client via JavaScript, but it also provides a number of easily-used visual DHTML effects. Is this a conceptual confusion on the part of those who refer to these as "AJAX libraries"? Possibly. Is it nonetheless extremely convenient to have tight integration between the code which talks to the server and the code which displays the retrieved resources? Absolutely. Does this mean that "AJAX libraries" will probably continue to include visual DHTML effects for the foreseeable future? Yes. And XMLHttpRequest is not a visual effect; a visual effect causes a visible change in the page. But an XMLHttpRequest, by itself, does no such thing; it simply retrieves a resource from a server. Only when combined with DHTML techniques to present the returned resource does a "visual effect" take place. -- "May the forces of evil become confused on the way to your house." -- George Carlin
