1 Reply Latest reply on Dec 13, 2006 10:32 PM by Ly Le

    Help with application scope bean

    Ly Le Newbie

      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.