Render h:panelGrid on dataTable row select?

I have a dataTable that when a user selects a row a number of fields are populated so they can see more detail. of that particular item. However, at the moment the page loads with the unpopulated panelgrid and populates on selecting of a row. How 开发者_JAVA技巧can I hide this panelgrid and get it to show once the row has been selected??

Thanks

Use the rendered attribute and let it evaluate true if anything has been selected.

E.g.

<h:panelGrid rendered="#{not empty bean.selectedRow}">
    <h:outputText value="#{bean.selectedRow.foo}" />
    <h:outputText value="#{bean.selectedRow.bar}" />
    ...
</h:panelGrid>