Using Explicitly Defined Breadcrumbs
To provide a simple navigation hierarchy where you define the navigation items for the breadcrumbs, you can add the af:breadCrumbs component to each page, with one or more af:commandNavigationItem components that you explicitly set. The value of the af:commandNavigationItem component’s attributes may be set to a page or to an EL expression.
For example, in a shopping application you may want to enable the user to follow breadcrumbs to display categories and subcategories of products, rather than pages, as shown in the example in the slide. Instead of static values, you can use parameters and action listeners to make these breadcrumbs dynamic, displaying the names of the categories and subcategories by using EL expressions that evaluate to changing parameter values.