Overview: Developing a dynamic UI configuration

Overview: Developing a dynamic UI configuration

Get an overview of the main tasks involved in creating a dynamic UI configuration.
The following describes a general overview of the main tasks involved in creating a dynamic UI configuration.

Planning
Create the extension node for containing dynamic pages
Develop the portlet definition for dynamic portlets
Develop the page definition for dynamic pages
Develop the dynamic UI launching portlet
Provide controls for closing dynamic UIs.
Test the configuration
Deploy the configuration

Only standard portlets can launch dynamic UIs. IBM portlets, however, can be launched as dynamic portlets and receive properties. Standard portlets can also launch dynamic pages containing a mixture of standard and IBM portlets.
Planning. Determine the requirements of the dynamic UI configuration. The following are some of the questions that can help you in the planning process.

What is the layout of the page definition?

Should the page definitions be viewable by users? If not, where in the portal topology should they be placed?

Where should the extension node be placed in the portal topology?

What information needs to be passed to each dynamic UI? How will the portlets use that information?

How will the UI be closed? Should we use tags to allow the user to close dynamic pages and dynamic portlets? If not, is it the responsibility of the calling portlet or a dynamic portlet to close the UI?

Create the extension node for dynamic pages.

Create the page to be used for containing dynamic UIs.

Assign a unique name to the node. To do this, use the Unique names portlet.

Open a UNIX System Services (USS) command prompt and run...

cd PROFILE_ROOT/ConfigEngine.
./ConfigEngine.sh action-enable-page-as-extension-node-wp.dynamicui.config -DPageUniqueName=pageUniqueName [-DVirtualPortalContext=virtualPortalContext]

...where pageUniqueName is the unique name of the extension node and virtualPortalContext is the context of the virtual portal that the specified page is part of. The -DVirtualPortalContext flag is needed only in the case where a virtual portal is used.
This command designates the page as an extension node. If you subsequently need to remove the extension node designation, run the command using the action-disable-page-as-extension-node-wp.dynamicui.config task.
Develop the portlet definition for dynamic portlets. Any existing portlet can be used as the definition for a dynamic portlet. For standard portlets, be sure to set the ID attribute for the <portlet-app/> element in the portlet.xml The launching portlet uses this value, plus the <portlet-name/>, to obtain the object ID of the portlet definition. For IBM portlets, the uid attribute of the <portlet-app/> element is used. Determine what properties need to be passed to the portlet.
Portlet deployment descriptors considerations
To receive portlet properties, the com.ibm.portal.context.enable preference parameter must be set in the portlet.xml with a value of true. By default, this value is set to false.
For standard portlets:
<portlet-preferences>

   ...
    <preference>
    <name>com.ibm.portal.context.enable</name>
    <value>true</value>
   </preference>
   ...
</portlet-preferences>
For IBM portlets
...
   <config-param>
      <param-name>com.ibm.portal.context.enable</param-name>
      <param-value>true</param-value>
   </config-param>
...  
Additionally, also modify the file web.xml for IBM portlets to receive portlet properties. The servlet class entry should specify the com.ibm.wps.pb.wrapper.PortletWrapper class. SeePackaging, deploying and compiling cooperative portlets for more information and an example.
Considerations for retrieving context
Standard portlets receive page properties on the processAction() method using the com.ibm.portal.context request attribute. The value of this attribute is a Map storing the context entries. Each property value is obtained by name. The name and value of each property value is determined by the requirements of the dynamic UI configuration.To get a value for the property with name <propertyName> do the following:
public void processAction (ActionRequest request, ActionResponse response) 
   throws PortletException, java.io.IOException
{
    // perform application specific action handling    
    ...
    // perform page context processing        
    String specialAction = request.getParameter("com.ibm.portal.action");
     if (specialAction != null &&
       specialAction.equals("com.ibm.portal.context.receive"))     
     {
      //this indicates context was passed to the launched page       
      java.util.Map contextMap = (java.util.Map)
      request.getAttribute("com.ibm.portal.context");

      Object propertyValue =  (Object) contextMap.get(<propertyName>);
             portletSession.setAttribute(<propertyName>, propertyValue);
            }

}
IBM portlets must implement the PropertyListener interface that provides the setProperties() method, which provides the page properties as an array of PropertyValue objects. In this sample, a loop is used to scan the array for the task properties.
public void setProperties(PortletRequest request, PropertyValue contextArray[])
{
          Object propertyValue;

   for (int i = 0; i < contextArray.length; i++)     {
      String propertyName = contextArray[i].getProperty().getName();

      if(propertyName.equals(<propertyName>))
      {
         propertyValue = (Object)contextArray[i].getValue();
      }
            }

   request.getSession().setAttribute(<propertyName>, propertyValue);
       }
IBM portlet considerations

To receive portlet properties, the com.ibm.portal.context.enable configuration parameter is specified in the portlet.xml. This parameter plays the same functional role as the standard portlet preference. Additionally, also modify the web.xml file to receive portlet properties. The servlet class entry should specify the com.ibm.wps.pb.wrapper.PortletWrapper class.
See the Packaging, deploying and compiling considerations section for more information.
Develop the page definition for dynamic pages.

Create the layout and content of the page definition from which dynamic pages are launched. For development purposes, we can use Manage Pages as you work with the visual layout.

Assign a unique name to the page using the Unique names portlet. The portlet uses this name to lookup the object ID of the page definition.
Develop the dynamic UI launching portlet
Use JNDI lookup, obtain a reference to the required portlet services.
private DynamicUIManagementFactoryService dynamicUIManagerFactoryService;
private RedirectURLGeneratorFactoryService redirectService;
PropertyFactory propertyFactory;
...

// Obtain a reference to the Dynamic UI Management Factory service 
PortletServiceHome dynamicUIManagerFactoryServiceHome = (PortletServiceHome)
ctx.lookup("portletservice/com.ibm.portal.portlet.service.dynamicui.DynamicUIManagementFactoryService");
dynamicUIManagerFactoryService = (DynamicUIManagementFactoryService) dynamicUIManagerFactoryServiceHome.getPortletService(DynamicUIManagementFactoryService.class);

// Obtain a reference to the property factory
PortletServiceHome serviceHome = (PortletServiceHome) ctx.lookup("portletservice/com.ibm.portal.propertybroker.service.PropertyFactory");
     propertyFactory = (PropertyFactory)serviceHome.getPortletService(com.ibm.portal.propertybroker.service.PropertyFactory.class);


// If the dynamic UI should be displayed immediately upon launch, 
// obtain a reference to the RedirectURLGeneratorFactory service     
PortletServiceHome redirectServiceHome = (PortletServiceHome) ctx.lookup("portletservice/com.ibm.portal.portlet.service.state.RedirectURLGeneratorFactoryService");

   redirectService = (RedirectURLGeneratorFactoryService) redirectServiceHome.getPortletService(RedirectURLGeneratorFactoryService.class);
Obtain the object ID of the page definition or portlet definition. This can be done using either a unique name (for a page or portlet definition) or portlet name + portlet-app ID (portlet definition only).
Use a unique name:
Context ctx = new InitialContext();

...

Name uniqueName = new CompositeName("portal:uniquename");

uniqueName.add(yourUniqueName);
ObjectID oidForName = (ObjectID) ctx.lookup(uniqueName);
Use portlet name + porlet-app id:
Context ctx = new InitialContext();

...

Name portletName =  new CompositeName("portal:config/portletdefinition");
portletName.add(appID);
portletName.add(portletName);

ObjectID portletDefOID = (ObjectID) ctx.lookup(portletName);
Obtain an instance of the DynamicUICtrl interface from the factory. The factory expects the Render/ Action Request/Response followed by the configuration name (String) as input parameters. The DynamicUICtrs that is returned is parameterized with the request/response. The DynamicUICtrl must be obtained once per request and should not be stored.
DynamicUICtrl DynamicUICtrl = dynamicUIManagerFactoryService.getDynamicUICtrl(request, response, extensionNode);
Create the properties that need to be passed to the dynamic UI.
PropertyController property1 = propertyFactory.createProperty(config);  property1.setName(propertyKey);
property1.setClassname("java.lang.String");
property1.setDirection(Direction.OUT);

PropertyValue value = propertyFactory.createPropertyValue(request, property1, propertyValue);
PropertyValue[] propertyValues = new PropertyValue[1];
propertyValues[0] = value;   
Launch the dynamic UI using the addPage() or addPortlet methods and passing the object ID of the page/portlet definition. Example of launching a page:
DynamicUICtrl.addPage(pageDefinitionID, new LocalizedImpl(title,description), propertyValues);
Optional: Navigate the user to the newly launched page using a redirect.
RedirectURLGenerator redirector = redirectService.getURLGenerator(request, response);
EngineURL redirectURL = redirector.createPortletURL(launchedPortlet);

response.sendRedirect(redirectURL.toString());
Provide controls for closing dynamic UIs. In many cases we can allow the user to explicitly close a dynamic UI from a theme or skin. These icons are enabled using the <portal:closePage/> and <portal:closePortlet/> tags. See Tags used by the portal JSPs for more information.
As an alternative, the launching portlet can close a dynamic UI using the removePage() or removePortlet() methods of the DynamicUICtrl interface, providing the object ID of the dynamic UI as input on the call. If removing a dynamic portlet, the calling portlet must be on the same page.

Test the configuration. Each dynamic UI configuration has its own requirements, design, and implementation, and therefore, a different set of test cases. However, you should always verify the following general behaviors.

Pages and portlets are created and removed successfully.

Each time a dynamic UI is launched, a new instance of the page or portlet is created or, in the case of shared dynamic UIs, the user is returned to an existing instance.

Properties are passed and processed by the dynamic portlets as expected.

As portlets are added and removed from a dynamic page, the page maintains a balanced layout.

Deploy the configuration When the dynamic UI configuration is ready to be promoted to a production level server, create the XMLAccess scripts containing the necessary page and portlet definitions. We can use the Manage Pages portlet to export the page configuration to XMLAccess, including any wires or unique names used by the configuration.
Parent: Dynamic user interfaces