Problems with AsyncTask

I'm an Android newbie and I've been having problems with this code:

http://ift.tt/1vbxIpm

I've tried to refactor but it does not work.

This is the output: Error:(20, 21) error: no suitable method found for add(int,ForecastFragment) method FragmentTransaction.add(Fragment,String) is not applicable (argument mismatch; int cannot be converted to Fragment) method FragmentTransaction.add(int,Fragment) is not applicable (argument mismatch; ForecastFragment cannot be converted to Fragment)

Thanks in advance