p:treeTable and h:selectOneMenu - jsf

Question

I got a <p:treeTable> that works perfectly as showcase, I open a dialog to see the detail of each node... the dialog have a <h:selectOneMenu> and it's not working. I don't know why, send me the error "Target Unreachable" but if I put the attribute into a <h:outputText> it's working (it means that it's not null). What is happening?
<p:row>
<p:column colspan="4" style="width:800px">
<p:dialog id="edit" widgetVar="edit" header="Edit" showEffect="clip"
hideEffect="explode" position="center,center" width="520" modal="true" closable="false"
closeOnEscape="true" resizable="false" dynamic="true">
<h:panelGrid width="100%">
<p:row>
<p:column >
Name
</p:column>
<p:column>
<p:inputText value="#{levelBean.selectedLevel.name}" />
</p:column>
</p:row>
<p:row>
<p:column >
Description
</p:column>
<p:column>
<p:inputText value="#{levelBean.selectedLevel.description}" />
</p:column>
</p:row>
<p:row>
<p:column >
Level
</p:column>
<p:column>
<!-- this its showing OK !! -->
<h:outputText value="#{levelBean.selectedLevel.id.idLevel}"/>
<!-- this mark target unreachable -->
<h:selectOneMenu id="cbo" style="width=200px"
value="#{levelBean.selectedLevel.id.idLevel}" >
<f:selectItems value="#{cboLevelBean.list}" var="levelEdit"
itemValue="#{levelEdit.id.idNivel}"
itemLabel="#{levelEdit.name}"
/>
</h:selectOneMenu>
</p:column>
</p:row>
</h:panelGrid>
</p:dialog>
<p:treeTable id="treeTableLevels" value="#{levelBean.root}" var="subLevel" style="width:800px">
<f:facet name="header">
Levels
</f:facet>
<p:column headerText="#{subLevel.object.levelName}">
<h:outputText value="#{subNivel.object.nameSubLevel}" />
</p:column>
<p:column style="width:24px">
<p:commandLink update=":levelsForm:edit" oncomplete="PF('edit').show()" title="Level Detail" styleClass="ui-icon ui-icon-search">
<f:setPropertyActionListener value="#{subLevel}" target="#{levelBean.selectedLevel}" />
</p:commandLink>
</p:column>
</p:treeTable>
</p:column>
</p:row>
Thanks for any help!!

Answer 1

I fond the reason... I just put the selectonemenu into another form and it works.. but I don't know why.. can somebody explain?
<h:form id="someform">
<p:selectOneMenu id="cbo" style="width: 200px"
value="#{levelBean.selectedLevel.id.idLevel}">
<f:selectItems value="#{cboLevelBean.list}" var="levelEdit"
itemValue="#{levelEdit.id.idNivel}"
itemLabel="#{levelEdit.name}"/>
</p:selectOneMenu>
</h:form>
Anyway hope this help to others!