This interface is intended to be implemented by classes that
also implement Element to indicate whether a particular
Element should be auto-expanded in the navigator upon creation.
When an Element says that it is not auto-expandable in a particular
Context, it means that auto-expansion will stop at that point in
The implementation of this method should return true
if this Element is allowed to be auto-expanded. If false
is returned, it means that auto-expansion will occur up to this
Element but not drill in any further.
expansionContext - The auto-expansion Context. This Context
is not necessarily the context of this Element, but it is the
Context where auto-expansion was initiated. It is also possible
that the expansionContext will be null if there is
a reason that a Context could not be provided. Implementations
need to check for null before dereferencing expansionContext.