The goal here is to define of there are data into the table, if not, we hide the subform. That means, we hide the whole table (border and header line).
There are several ways to proceed, this is one :

Table from context is binded like :
- TABLE_TEXT_HEADER_PO binded with $.TABLE_HEADER
- LINE_TEXT_HEADER_PO binded with $.DATA[*] (repeat subform for each data item is ticked)
- HEADER_PO_TEXT binded with $.TEXT_CONTENT