Android :: Get Mail Sent Notification In Activity Result

I am launching a mail activity by
//Sending mail final int SENT_MAIL = 1;
startActivityForResult(Intent.createChooser(i, "Send mail"),SENT_MAIL);
and in
onActivityResult(int req, int res,Intent data)

I am trying to find the result of email sending, so as to confirm if my mail was sent or was discarded by the user. I am receiving null for Intent data.
i.e. data =null
parameter in onActivityResult(int req, int res, Intent data), res is always 0.
ie. res = 0;