Sometimes we need refresh or access components from region but the problem is that, these components are binding in a bean of master page.
Typical example is when you have a paneltab where each tab is a region and you need access acomponent for master page.
In this case you can make use of Parent Action, for invoke a parent action activity.
The schema is showed in next diagram:
Another way is get a instance of master bean from region bean.
ExternalContext exctxt = FacesContext.getCurrentInstance().getExternalContext(); MasterBean mBean = (MasterBean) exctxt.getRequestMap().get("MasterBean");
Oficial Doc: Using Parent Action Activities