Olaf Heimburger's Blog

While developing my application I reused a number of pages for different pages flows for different user roles. This resulted in the need for different sub menus (aka "menu2" facet in <af:panelPage>).

The Approach

Instead of putting the sub menu in every page, I've chosen to use <af:region> to reduce the code and be more flexible during the design. This region uses a member of the application's state bean. (An implementation detail of my application - see the SRDemo for a similar approach to store context information). The region itself retrieves the menu context and decides which menu to display.

Using a Region

Using a Region within a .jspx page is quite easy. Instead of your ADF Faces tags use the <af:region> tag to reference the specific region:

<f:facet name="menu2">
 <af:region id="menu2Region"
            regionType="demo.regions.menu2">
  <f:attribute name="create" value="false" />
 </af:region>
</f:facet>

Define a Region Mapping

To use a region we must tell ADF Faces where to find the definition of the region. This will be done in the WEB-INF/region-metadata.xml file.

<component>
 <component-type>demo.regions.menu2</component-type>
 <component-class>oracle.adf.view.faces.component.UIXRegion</component-class>
 <component-extension>
  <region-jsp-ui-def>/regions/subMenu.jspx</region-jsp-ui-def>
 </component-extension>
 <attribute>
  <attribute-name>create</attribute-name>
  <attribute-class>java.lang.String</attribute-class>
 </attribute>
</component>

This example also shows that a region can have parameters (or attributes) that are used within the region definition. You see the usage of parameters above.

Define a Region

Finally we define the region in a separate file which contains the complete tags we'd like to use.

<af:regionDef var="aParam"
 xmlns:f="http://java.sun.com/jsf/core"
 xmlns:af="http://xmlns.oracle.com/adf/faces">
 <!-- ... -->
</af:regionDef>

Don't forget to define the namespaces in the <af:regionDef> tag to make JDeveloper Code-Insight happy.

The Dynamic Region Content

Essentially, you put every tag you want to use within the <af:regionDef> tag. To add a bit dynamic for the context-based menu display, I've put the <af:switcher> around my different versions of the menus. Every possible case is wrapped by a normal JSF <f:facet> tag.

<af:switcher defaultFacet="default"
 facetName="#{userState.menuContext}">
 <f:facet name="organisation">
  <af:menuBar>
   <af:commandMenuItem
    text="#{res['page.organisation.create']}"
    action="createOrganisation"
    rendered="#{!userState.patientRole}"
    immediate="true"
    selected="#{aParam.create == 'true'}"/>
  </af:menuBar>
 </f:facet>
 <!-- more facets here -->
</af:regionDef>

Please note, how I determine the current menu context from the application context bean with facetName="#{userState.menuContext}".

We also see how the parameters are used. As these are Strings we have to compare them with literal values.

Setting the Menu Context

When I change the main menu context, an action is called and sets the current menu context field in the application context bean. Here is a sample of the action:

public String organisationAction() {
  setMenuContext("organisation");
  return "GlobalOrganisation";
}

Since the navigation  rule for the menus is designed as a global outcome ("GlobalOrganisation"), I've placed this action in the application context bean, too.

Conclusion

This sample is a fast, usable, and easy to understand solution (important for co-workers, or when I have to maintain it in two weeks time). There are more flexible solutions in ADF Faces available, but often much harder to read, maintain, etc.