ADF Faces and BC: Scope problem with managed bean

Question

Hi,
I am using JDev 10.1.3 and ADF Faces with ADF BC.
I have created a managed bean which needs to interact with the binding layer and also receive actions from the web pages. I have a managed property on the bean which is defined as follows:
<managed-bean>
    <managed-bean-name>navigator</managed-bean-name>
    <managed-bean-class>ecu.ethics.view.managed.Navigator</managed-bean-class>
    <managed-bean-scope>session</managed-bean-scope>
    <managed-property>
      <property-name>bindings</property-name>
      <value>#{bindings}</value>
    </managed-property>
  </managed-bean>I need the been to session scope because it needs to keep previous and next pages to navigate the user through their proposal. If i use session scope (as above) i get the following error when i click on a comand link which references a method in the above bean: #{navigator.forwardNext_action} which returns a global forward.
this is the exception:
javax.faces.FacesException: #{navigator.forwardNext_action}:
javax.faces.el.EvaluationException: javax.faces.FacesException:
javax.faces.FacesException: The scope of the referenced object: '#{bindings}' is shorter than the referring object     at
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:78)     at
oracle.adf.view.faces.component.UIXCommand.broadcast(UIXCommand.java:211) at
javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:267)at
javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:381)     at
com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:75)     at
com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:200)     
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:90)     at
javax.faces.webapp.FacesServlet.service(FacesServlet.java:197)how can i get around this?
Brenden

Answer 1

Hi pp,
you need to create a managed (not backing) been set to session scope.
You can call/reference the managed bean from your page.
the backing bean is designed around a page lifecyle which is request oriented in it's design.
This is a simple managed bean from faces-config.xml
<managed-bean>
    <managed-bean-name>UserInfo</managed-bean-name>
    <managed-bean-class>ecu.ethics.admin.view.managed.UserInfo</managed-bean-class>
    <managed-bean-scope>session</managed-bean-scope>
      <managed-property>
      <property-name>bindings</property-name>
      <property-class>oracle.adf.model.BindingContext</property-class>
      <value>#{data}</value>
    </managed-property>
  </managed-bean>and the getters and setters for bindings in your session scope managed bean:
    public void setBindings(BindingContext bindings) {
        this._bindings = bindings;
    public BindingContext getBindings() {
        return _bindings;
    }you can access the model from the managed bean using the the BindingContext if needed.
also have a look at JSFUtils from the ADF BC SRDemo application, there are methods in this class such as resolveExpression which demonstrate how to get the values of items on your page programatically using expression language. You can use this in your managed bean to get values from your pages.
regards,
Brenden