How to render or hide a jsf subview based on a method call (which returns boolean)?

Question

I have a context loader class which loads an XML file with info on which components to show or hide on a page. On the JSP pages, within the 'rendered' attribute for a subView,, I would like to make a call to ContextLoader.displayPageComponent(String pageId, String componentId) which returns a boolean. Does this work in JSF? If not, is there another way to achieve the same?

Answer 1

The most direct way to do this would be have a backing bean with a method like this...

public boolean isRenderSubview1Comp1() {
   return ContextLoader.displayPageComponent("subview1", "comp1");
}

with

<h:outputText value="foo" rendered="#{MyBean.rednerSubview1Comp1}"/>

Answer 2

Wrap it in an EL function. How to do it exactly depends on the view technology in question. You can find a JSP-targeted example in this answer and a Facelets-targeted example in this answer.