How do you pass view parameters when navigating from an action in JSF2?

Check out these:

• http://andyschwartz.wordpress.com/2009/07/31/whats-new-in-jsf-2/#get
• http://mkblog.exadel.com/2010/07/learning-jsf2-page-params-and-page-actions/

You're gonna need something like:

<h:link outcome="success">
  <f:param name="foo" value="bar"/>
</h:link>

...and...

<f:metadata>
  <f:viewParam name="foo" value="#{bean.foo}"/>
</f:metadata>

Judging from this page, something like this might be easier:

 <managed-bean>
   <managed-bean-name>blog</managed-bean-name>
   <managed-bean-class>com.acme.Blog</managed-bean-class>
   <managed-property>
      <property-name>entryId</property-name>
      <value>#{param['id']}</value>
   </managed-property>
 </managed-bean>

The unintuitive thing about passing parameters in JSF is that you do not decide what to send (in the action), but rather what you wish to receive (in the target page).

When you do an action that ends with a redirect, the target page metadata is loaded and all required parameters are read and appended to the url as params.

Note that this is exactly the same mechanism as with any other JSF binding: you cannot read inputText's value from one place and have it write somewhere else. The value expression defined in viewParam is used both for reading (before the redirect) and for writing (after the redirect).

With your bean you just do:

@ManagedBean
@RequestScoped
public class MyBean {

private int id;

public String submit() {
    //Does stuff
    id = setID();
    return "success?faces-redirect=true&includeViewParams=true";
}

// setter and getter for id

If the receiving side has:

    <f:metadata>
        <f:viewParam name="id" value="#{myBean.id}" />
    </f:metadata>

It will do exactly what you want.

Without a nicer solution, what I found to work is simply building my query string in the bean return:

public String submit() {
    // Do something
    return "/page2.xhtml?faces-redirect=true&id=" + id;
}

Not the most flexible of solutions, but seems to work how I want it to.

Also using this approach to clean up the process of building the query string: http://www.warski.org/blog/?p=185