ajax theme
NOTE: Ajax template (Dojo plugin) is deprecated and won’t be supported any longer.
The ajax theme extends the xhtml theme with AJAX features. The theme uses the popular DOJO AJAX/JavaScript toolkit. AJAX features include:
- AJAX Client Side Validation
- Remote form submission support (works with the submit tag as well)
- An advanced div template that provides dynamic reloading of partial HTML
- An advanced a template that provides the ability to load and evaluate JavaScript remotely
- An AJAX-only tabbedpanel implementation
- A rich pub-sub event model
- Interactive autocomplete tag
See also: Ajax tags
Browser Compatibility
AJAX (as a technology) uses a browser-side scripting component that varies between browsers (and sometimes versions). To hide those differences from the developer, we utilize the dojo toolkit (http://www.dojotoolkit.org). Several browsers are supported by dojo, and any UI’s created with the ajax theme should act the same way for supported browsers. The supported browsers are:
- IE 5.5+
- FF 1.0+
- Latest Safari (on up-to-date OS versions)
- Latest Opera
- Latest Konqueror
Extending the AJAX Theme
The wrapping technique utilized by the ajax theme is much like xhtml theme, but the controlheader.ftl
is a wee bit different.
<#if parameters.label?if_exists != "">
<#include "/${parameters.templateDir}/xhtml/controlheader.ftl" />
</#if>
<#if parameters.form?exists && parameters.form.validate?default(false) == true>
<#-- can't mutate the data model in freemarker -->
<#if parameters.onblur?exists>
${tag.addParameter('onblur', "validate(this);${parameters.onblur}")}
<#else>
${tag.addParameter('onblur', "validate(this);")}
</#if>
</#if>
The header provides for AJAX Client Side Validation by checking
if the validate
attribute is set to true. If it is, a validation request is made on each onblur
event
for a HTML Struts Tags. Some people don’t like the onblur
behavior; they would rather a more
advanced timer (say, 200ms) be kicked off after every keystroke. You can override this template and provide that
type of behavior if you would like.
Special Interest
Three ajax_xhtml templates of special interest are head
, div
, and a
.
Especially with the ajax theme, it is important to use the head tag. (See the ajax head template for more information.) Without it, AJAX support may not be set up properly.
In addition to these templates, be familiar with the ajax event system provided by the framework and Dojo.