Problematic class

gistfile1.java

// what package should Fragment belong to? I want to use it in Gingerbread!
public class MyFragment extends Fragment {

    private TextView   mTextView;
    // Holding references to Activities is a no no.
    // You are leaking its whole view hierarchy
    private MyCallBack mMyCallBack;

    // In fragments inflating views happens on onCreateView
    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.fragment_my);

        mTextView = (TextView) findViewById(R.id.textview);
    }

    // Activity will be null the first time this method is called.
    // we should interact with the Activity in onResume() or onActivityCreated()
    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        mMyCallBack = (MyCallBack) activity;
        mMyCallBack.onAttach();
    }

    @Override
    public void onResume() {
        super.onResume();
        mTextView.setText("Welcome to your fragment.");
        // We should not do file I/O here
        if (!checkDatabaseForSyncResource()) {
            new MyAsyncTask().execute("resourceA");
        } else {
            mMyCallBack.resourceLoaded();
        }
    }

    // what happens if the Activity and Fragment are no longer around when this returns?
    private class MyAsyncTask extends AsyncTask<String, Void, String> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }

        @Override
        protected String doInBackground(String... params) {
            mTextView.setText("Started downloading something");
            return goGetATokenFromServer(params);
        }

        @Override
        protected void onProgressUpdate(Void... values) {
            super.onProgressUpdate(values);
        }

        @Override
        protected void onPostExecute(String s) {
            mMyCallBack.setToken(s);
            persistTokenDbSync(s);
        }
    }
}