commandButton action not executed

problem description:

I have a page that has the following commandButton.

<h:commandButton value="Update List" action="#{todoListBean.update}"
rendered="#{todoListBean.todoList.listId ne 0}" />

When I click on the button it doesn't execute the action it just
refreshes the page.  But if I remove the rendered property so the
commanButton tag looks like:

<h:commandButton value="Update List" action="#{todoListBean.update}" />

jsf will execute the action #{todoListBean.update}.  Does anyone know
why when I have the rendered property in the jsf tag the action doesn't
get executed?

http://203.208.39.132/search?q=cache:WZkHHRpUdvMJ:www.nabble.com/commandButton-action-not-executed-td16456333.html+commandButton+rendered&cd=11&hl=zh-CN&ct=clnk&gl=cn&st_usg=ALhdy2-0IFh3SVY7lduxLQYW3xJkGUVFYg

 

http://203.208.37.132/search?q=cache:M1K5BMl8PK8J:forums.sun.com/thread.jspa%3FthreadID%3D5285344+commandButton+rendered+action&cd=10&hl=zh-CN&ct=clnk&gl=cn&st_usg=ALhdy2_CbIRHOTzFBf44a0kPd9K7ZptYxw