Network Deployment (Distributed operating systems), v8.0 > Develop and deploying applications > Develop Portlet applications > Portlet aggregation and preferences
Portlet coordination
We can use either the events mechanism or the public render parameters mechanism to coordinate portlets within a portal.
JSR 286 defines these two mechanisms as follows:
- Events: Loose-coupling of portlets during action phase.
- Public render parameters: Sharing of view state between portlets.
The WAS portlet container supports both concepts with one exception. The wiring of events on a portal level is not supported.
To make use of the public render parameters on a portal page defined with the aggregation tag library, explicitly declare the portal scope:
<%@ taglib uri="http://ibm.com/portlet/aggregation" prefix="portlet" %> <%@ page isELIgnored ="false"%><!-- define portal scope for public render parameters --> <portlet:scope> <portlet:portlet context="/simpleportlet" portletname="SimplePortlet1" windowId="id1"/ <portlet:portlet context="/simpleportlet2" portletname="SimplePortlet2" windowId="id2"/> </portlet:scope><portlet:init portletURLPrefix="/my-webapp-context/my-portal-jsp-url-pattern/"> <!-- insert your portlets here, wrapped with your html markup --> ... <portlet:insert url="simpleportlet/SimplePortlet1" windowId="id1" titleVar="portlettitle_1"/> ... <portlet:insert url="simpleportlet2/SimplePortlet2" windowId="id2" titleVar="portlettitle_1"/> ... </portlet:init>The public render parameters are only visible to the portlet windows mentioned within this defined scope. This condition assumes, as a prerequisite, that the corresponding portlets have also declared support for a given public render parameter in their portlet.xml file, according to the JSR 286 specification:
... <portlet> <portlet-name>portlet_name1 </portlet-name> ... <supported-public-render-parameter>foo </supported-public-render-parameter> </portlet> <portlet> <portlet-name>portlet_name2 </portlet-name> ... <supported-public-render-parameter>foo </supported-public-render-parameter> </portlet> <public-render-parameter> <identifier>foo </identifier> <qname xmlns:x="http://example.com/params">x:foo2 </qname> </public-render-parameter> ...
Portlet container
Portlet aggregation using JSP
Portlet URL security
Supported optional features of the JSR-286 Portlet Specification
Task overview: Managing portlets
Configure portlet fragment caching
Related
Portlet container settings
Aggregation tag library attributes
JSR 286 Portlet Specification
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