poll doesn't work with setted var - jsf

Question

I want to use one html page with two ManagedBeans. Depending on the parameter in the URL, I want to set the bean name through JSTL variable. For example:
<c:set var="bean" value="#{webModule1}" scope="request" />
or
<c:set var="bean" value="#{webModule2}" scope="request" />
I have class which was use all this time, so for sure this works:
#ManagedBean(name = "webModule1")
#ViewScoped
public class WebModule1 implements Serializable {
protected WebModulesFormBean form;
#PostConstruct
public void init() {
if (!firstInit()){
this.form= new WebModulesFormBean();
}
//some code
}
public void process() {
if(this.form.isActive()){
//some code
}
}
}
And new one:
#ManagedBean(name = "webModule2")
#ViewScoped
public class WebModule2 extends WebModule1 {
public void process() {
if(this.form.isActive()){
//code with some changes
}
}
}
This solutions works with value attribute and form in not null, for example:
<p:treeTable value="#{bean.form.root}" var="node" id="modulesTree">
But I have problem with this piece of code:
<p:poll listener="#{bean.process()}" widgetVar="documentOutcome" autoStart="#{bean.form.start}" update="modulesTree" async="false"
interval="1" id="myPoll2" />
When listener is called, NullPointerException appears.
And this problem is with all p:polls (I have a few), so this is not a problem with method code.
Problem is that 'form' is null, although at the beginning variable 'form' is initialized and treeTable is shown at the page. So 'form' starts to be null when the listener is called.
Thanks!

Answer 1

I have a solution!
The problem was with:
<c:set var="bean" value="#{webModule1}" scope="request" />
scope="request" was not enough and in my understanding this scope meant that when poll was called, a new bean reference was created and form variable was null because it was not a firstInit().
scope="view" is the solution.
Thank you for comments!