JSF ajax calls supported with ViewScope bean?

Question

Do ViewScope beans allow ajax calls?

For example:

Here is a xhtml page:

<h:body>
        <h:selectOneMenu value="#{test.selected}">
            <f:selectItem itemValue="2" itemLabel="2" />
            <f:selectItem itemValue="3" itemLabel="3" />
            <f:ajax listener="#{test.updateData()}" />
        </h:selectOneMenu>
</h:body>

Here is the ViewScoped Bean:

@ViewScoped
@Named
public class test implements Serializable{
    private String selected;


    public void updateData(){
        System.out.println("Ajax call successful.");
    }

    public String getSelected() {
        return selected;
    }

    public void setTest(String test) {
        this.selected = selected;
    }
}

When I tried this, it didn't work.

You're not terribly clear on "didn't work". I'll for simplicitly assume that you don't see anything printed to the stdout. In the future, please elaborate the problem in developer's perspective instead of in enduser's perspective. Is the JS/ajax function invoked? (read JS console for errors) Is the HTTP request properly sent? (read HTTP traffic monitor in Network section in browser's developer toolset) Is the bean constructed and are the methods invoked? (put breakpoints, run a debugger, read server logs for exceptions, etc) What does the body of the returned HTTP response contain? Etc.. — BalusC, Apr 03 '13 at 11:50

score 4 · Accepted Answer · edited May 23 '17 at 11:48

Actually, you've 3 severe problems in the code posted so far:

The <h:form> is missing. Not sure though if this is careless preparation of the question or the actual code. The solution is obvious: put grouped UIInput and UICommand components in an independent <h:form>.
In the current JSF version, JSF's scope annotation @javax.faces.bean.ViewScoped doesn't work on CDI's bean management annotation @Named.

There are basically 3 solutions:
- Use CDI's @ConversationScoped instead. See also How to replace @ManagedBean / @ViewScope by CDI in JSF 2.0/2.1 for a concrete example. This has however the nasty side effect that it appends a cid request parameter to every outcome URL.
- Use MyFaces CODI to bridge JSF @ViewScoped to CDI. This has however the nasty side effect that it appends a windowId request parameter to every single outcome URL.
- Wait for JSF 2.2 to be released so that you can utilize the CDI compatible @javax.faces.view.ViewScoped annotation which ties it with the JSF view state.
This is however hardly the cause of your concrete problem as the bean action should just be invoked, but the bean will just behave like a @RequestScoped.
The setter method is missing. This should however have thrown a rather self-explaining PropertyNotWritableException to the server logs when the form is successfully submitted.

There is a fourth possible cause which can't be for sure be confirmed based on the information provided so far: a missing <h:head> would cause the <f:ajax> to fail because the required jsf.js couldn't be auto-included.

score 1 · Answer 2 · answered Apr 03 '13 at 08:28

You have a wrong setter which causes the error

public void setTest(String test) {
    this.selected = selected;
}

This must be

public void setSelected(String test) {
    this.selected = test;
}

As a side not, this setter is called for h:selectOneMenu value="#{test.selected}" which is fired when an item is selected on your combo box.

JSF ajax calls supported with ViewScope bean?

2 Answers2