try this:
Then, in B, I do:
Intent intent = getIntent();
intent.putExtra("Date",dateSelected);
setResult(RESULT_OK, intent);
finish();
And, in A:
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if(resultCode == RESULT_OK && requestCode==1) {
Bundle MBuddle = data.getExtras();
String MMessage = MBuddle.getString("Date");
}
}