LogoutDialogFragment.java

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    // Get the username from the arguments, if one isn't passed
    // we use a blank string so it still looks OK
    String username = "";
    if (getArguments().containsKey(USERNAME))
        username = ", " + getArguments().getString(USERNAME);

    // "Are you sure you want to log out, <username>?"
    String message 
        = getString(R.string.are_you_sure_you_want_to_log_out) +
          username +
          "?";

    AlertDialog.Builder b = new AlertDialog.Builder(getActivity());
    b.setTitle(R.string.log_out);
    b.setMessage(message) ;
    b.setPositiveButton(R.string.yes, this);
    b.setNegativeButton(R.string.no, this);

    return b.create();
}