PGPSignatureSubpacketVector hashedPcks vs unhashedPcks

How can i retrieve the  PGPSignatureSubpacketVector hashed and
unhashedPcks object??

I use  PGPSignatureSubpacketGenerator to create a
PGPSignatureSubpacketVector but I don't know how use it to create the
hashed and unhashed  PGPSignatureSubpacketVector.

I think that the object i generate is the unhashed one...
Please help me
FG