Hi,

I am a newbie with Seam and am trying to convert my JSF application to use Seam without ejb3.

I have an application scoped action object, which initialized a map of javabeans from the database, as below:

@Name("appManager")
@Scope(ScopeType.APPLICATION)
@Startup
public class GAHostAppManagedAction {

 @In
 private Session session;

 @Logger
 private Log log;

 private Map<String, List<Items>> hostAppsByHostName;

 public List<SelectItem> getHostList() {
 ... this instantiate and initialized a list SelectItem, containing String of host
 }

 @Create
 public void init() {
 ... get a list of Items and populate it to the map
 }
}

Here is my home.xhtml code snippet:

<h:form>
<h3>Please enter your name and password:</h3>
<h:panelGrid columns="2">
Name: <h:inputText value="#{user.userName}"/>
Password: <h:inputSecret value="#{user.userPassword}"/>
Host:
<h:selectOneMenu value="#{hostapp.host}">
<a4j:support action="#{hostapp.hostChanged}" event="onchange" reRender="applist" limitToList="true" ajaxSingle="true" requestDelay="20"/>
<f:selectItems value="#{appManager.hostList}"/>
</h:selectOneMenu>
Application
<h:selectOneMenu id="applist" value="#{hostapp.id}">
<f:selectItems value="#{appManager.appList}"/>
</h:selectOneMenu>
</h:panelGrid>
<br/>
<h:commandButton action="#{login.login}" value="Login"/>
</h:form>

It doesn't seem to work. I got the following exception when hitting the page home.jsf:

java.lang.IllegalArgumentException: Value binding '#{appManager.hostList}'of UISelectItems with component-path {Component-Path : [Class: org.ajax4jsf.framework.ajax.AjaxViewRoot,ViewId: /home.xhtml][Class: javax.faces.component.html.HtmlForm,Id: _id2][Class: javax.faces.component.html.HtmlPanelGrid,Id: _id4][Class: javax.faces.component.html.HtmlSelectOneMenu,Id: _id10][Class: javax.faces.component.UISelectItems,Id: _id12]} does not reference an Object of type SelectItem, SelectItem[], Collection or Map but of type : null
 at org.apache.myfaces.shared_impl.util.SelectItemsIterator.hasNext(SelectItemsIterator.java:144)
 at org.apache.myfaces.shared_impl.renderkit.RendererUtils.internalGetSelectItemList(RendererUtils.java:414)
 at org.apache.myfaces.shared_impl.renderkit.RendererUtils.getSelectItemList(RendererUtils.java:392)

Can any of you let me know what I did wrong?
Sorry, I am still trying to get familiar with Seam concepts and might have missed something.
Thanks a lot.