java - How to make a form tag comunicate to another form tag? -

i using jsf 2.2, primefaces , glassfish , have this:

<h:form id="formularioaltas">     //more code     <p:commandbutton value="guardar" action="#{altasbean.agregarrefaccion()}" /> </h:form>  <h:form id="myform" enctype="multipart/form-data" prependid="false" rendered="#{altasbean.estado}">     // more code here </h:form> 

and need formularioaltas tell myform value of boolean property estado has changed. uderstand doing simple update myform when commandbutton executed cant cause in diferent forms. needed way cause have problems uploading files server decided use 2 different forms. have working forms want show myform when commandbutton executed.

any ideas?

<p:commandbutton value="guardar" action="#{altasbean.agregarrefaccion()}" update=":myform" /> 

: because climb container hierarchy 1 step container contains both forms , myform because that's name.