AJAX support for markup
JBoss portal supports markup through tags on layouts and renderers of the pages.
Special tags are added to layout JSPs that facilitate the placement of AJAX
features on a page. Similarly, renderers are used to interpret the tags and to
render AJAX-driven content. The obvious advantage is the in-built support for
the auto-creation and control of AJAX components on portal pages.
Layout markup
As discussed earlier, layouts provide a structure for the creation and serving
of portal pages. Layouts aggregate all of the content generated by the portlet,
based on region and order, merge them with some additional content provided by
the portal, and serve a response back to the user. By providing support for
AJAX in the layout, helps facilitate the easy development and implementation of
dynamic functionality in pages, with minimal effort.
Layout markup is implemented using JSP tags. The JBoss JSP tag library,
portlet-layout.tld, offers tags that facilitate the implementation of AJAX
features in layouts. A JSP layout can be changed to an AJAX-supported page
simply by adding references to the tags. Hence, using tags also helps with the
easy implementation of features.
The following is the layout page from the default portal generic layout ${JBOSS_
PORTAL_HOME}\server\default\deploy\jboss-portal.sar\portal-core.war\
layouts\generic\index.jsp, and shows AJAX support implemented as tags:
<%@ page import="org.jboss.portal.server.PortalConstants" %>
<%@ taglib uri="/WEB-INF/theme/portal-layout.tld" prefix="p" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title><%=
PortalConstants.VERSION.toString() %></title>
<meta http-equiv="Content-Type" content="text/html;"/>
<!-- to correct the unsightly Flash of Unstyled Content. -->
<script type="text/javascript"></script>
<!-- inject the theme, default to the Renaissance theme if nothing is
selected for the portal or the page -->
<p:theme themeName="renaissance"/>
<!-- insert header content that was possibly set by portlets on the page
-->
<p:headerContent/>
<%@include
file="/layouts/common/modal_head.jsp"%>
</head>
<body id="body">
<p:region regionName='AJAXScripts' regionID='AJAXScripts'/>
<%@include
file="/layouts/common/modal_body.jsp"%>
</head>
<body id="body">
<p:region regionName='AJAXScripts' regionID='AJAXScripts'/>
<%@include
file="/layouts/common/modal_body.jsp"%>
<div id="portal-container">
<div id="sizer">
<div id="expander">
<div id="logoName"></div>
<table border="0" cellpadding="0" cellspacing="0" id="header-container">
<tr>
<td align="center" valign="top" id="header">
<!-- Utility controls -->
<p:region regionName=
'dashboardnav' regionID= 'dashboardnav'/>
<!-- navigation tabs and such -->
<p:region regionName=
'navigation' regionID='navigation'/>
<div id="spacer"></div>
</td>
</tr>
</table>
<div id="content-container">
<!-- insert the content of the 'left' region of the page, and assign the css
selector id 'regionA' -->
<p:region regionName='left' regionID='regionA'/>
<!-- insert the content of the 'center' region of the page, and assign the
css selector id 'regionB' -->
<p:region regionName='center' regionID='regionB'/>
<hr class="cleaner"/>
</div>
</div>
</div>
</div>
<div id="footer-container" class="portal-copyright">Powered by
<a class="portal-copyright" href="http://www.jboss.com/products/
jbossportal">JBoss Portal</a><br/>
</div>
<p:region regionName='AJAXFooter' regionID='AJAXFooter'/>
</body>
</html>
Renderer markup
The portal combines the renderers and layouts to generate the fi nal content.
Enabling support for AJAX in the renderer just requires adding the statement
<ajax-enabled>true</ajax-enabled> to the renderer descriptor.
The following example, at {JBOSS_PORTAL_HOME}\server\default\deploy\jbossportal.
sar\portal-core.war\WEB-INF\layout\portal-renderSet.xml, shows the renderer
confi guration of the emptyRenderer RenderSet for AJAX support:
<renderSet name="emptyRenderer">
<set content-type="text/html">
<ajax-enabled>true</ajax-enabled>
<region-renderer>
org.jboss.portal.theme.impl.render.empty.EmptyRegionRenderer
</region-renderer>
<window-renderer>
org.jboss.portal.theme.impl.render.empty.EmptyWindowRenderer
</window-renderer>
<portlet-renderer>
org.jboss.portal.theme.impl.render.empty.EmptyPortletRenderer
</portlet-renderer>
<decoration-renderer>
org.jboss.portal.theme.impl.render.empty.EmptyDecorationRenderer
</decoration-renderer>
</set>
</renderSet>
Also read
What is a Portlet? Explain its capabilities.
Explain Portal
architecture.
What is PortletSession interface?
What is
PortletContext interface?
Why
portals?...................
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