How to get field collection item under this View PHP

Hi All,

I don't know whether this is the right place to ask or should it be in field_collection module issue queue. Let me just place in two places.
Normally, I can retrieve a field value under this PHP through $data. But for the special field of type field collection (http://drupal.org/project/field_collection). I don't know how to retrieve its items.

Say I have a field_collection in content type A
There are two fields under this field_collection called
field_item1
field_item2

How can I retrieve field_item1 and field_item2 value in this View PHP in order to do some further processing?
Thanks