I am having a problem with getting the result from an asyncTask in a separate class. I have followed from a similar questions answer on here but I cant see where I have gone wrong.
My AsyncTask is in a separate class for easy calling, I needed to be able to have the notice that the asyntask had completed and then start the next activity.
I would welcome any help as I am not sure quite where I have gone wrong.
 public class StartScreen extends Activity{
ProgressDialog pd;
CountDownTimer waitTimer;
public static final String APP_PREFERENCES = "AppPrefs";
SharedPreferences settings; 
SharedPreferences.Editor prefEditor;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_start_screen);
     settings = getSharedPreferences(APP_PREFERENCES, MODE_PRIVATE);
    // getPreferences();
     //    prefEditor = settings.edit();
     waitTimer = new CountDownTimer(2000, 300) {
       public void onTick(long millisUntilFinished) {
          //called every 300 milliseconds, which could be used to
          //send messages or some other action
       }
       public void onFinish() {
          //After 2000 milliseconds (2 sec) finish current 
          //if you would like to execute something when time finishes 
           pd = ProgressDialog.show(StartScreen.this,"Title","Detail text",true,false,null);
           getPreferences();
       }
     }.start(); 
}   
private void getPreferences() {
    String UserName = settings.getString("UserName", null);
    if (UserName != null) {
        // the key does not exist
                Intent intent=new Intent(StartScreen.this,InitialPreferences.class);
                startActivity(intent);
            } else{
    //if (UserName.equals(UserName)){
        // handle the value
                dataTask();                 
                //pd.dismiss(); 
     }       
}   
        private void dataTask() {
    // TODO Auto-generated method stub
            new DATATask(this).execute(new FragmentCallback(){
                 @Override
                    public void onTaskDone() {
                     startMainAct();
                    }
                });
            }
         private void startMainAct() {
             Intent intent=new Intent(StartScreen.this,MainActivity.class);
                startActivity(intent);
            }
         public interface FragmentCallback {
                public void onTaskDone();
            }           
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.start_screen, menu);
    return true;
}
}
AsyncTask:
 public class DATATask extends AsyncTask<Void, Void, ArrayList<String>> {
     private FragmentCallback mFragmentCallback;
           public void execute(FragmentCallback fragmentCallback) {
                mFragmentCallback = fragmentCallback;
            }
           ArrayList<String> arr_data=new ArrayList<String>();             
           private Context context;
           public DATATask(Context context) 
           {
               this.context = context;
           }
           @Override
           protected void onPreExecute() {
               super.onPreExecute();
           }
            @Override
            protected ArrayList<String>  doInBackground(Void... params) {
                Document docVts, docTide;
                String shippingList, tideTimes;
                try {
                    docVts = Jsoup.connect("https://vts.mhpa.co.uk/main_movelistb.asp").timeout(600000).get(); 
                    Elements tableRows = docVts.select("table.dynlist td:eq(0),td:eq(1),td:eq(3),td:eq(4),td:eq(7),td:eq(8)");
                    tableRows.size();
                        for(int i = 1; i < 80; i++){//only allows x results from vts list, from 1 not 0. 0 produces needless results
                          shippingList = tableRows.get(i).text().replaceAll(" | ", "") +"\n";
                          arr_data.add(shippingList);// add value to ArrayList
                          System.out.println(shippingList);
                        };       
                         docTide = Jsoup.connect("http://www.mhpa.co.uk/search-tide-times/").timeout(600000).get();
                         Elements tideTimeOdd = docTide.select("div.tide_row.odd div:eq(0)");
                         Elements tideTimeEven = docTide.select("div.tide_row.even div:eq(0)");
                         Elements tideHightOdd = docTide.select("div.tide_row.odd div:eq(2)");
                         Elements tideHightEven = docTide.select("div.tide_row.even div:eq(2)");
                            Element firstTideTime = tideTimeOdd.first();
                            Element secondTideTime = tideTimeEven.first();
                            Element thirdTideTime = tideTimeOdd.get(1);
                            Element fourthTideTime = tideTimeEven.get(1);
                            Element firstTideHight = tideHightOdd.first();
                            Element secondTideHight = tideHightEven.first();
                            Element thirdTideHight = tideHightOdd.get(1);
                            Element fourthTideHight = tideHightEven.get(1);
                            System.out.println("first tide time: " + firstTideTime.text() + "   " + firstTideHight.text()); 
                            System.out.println("second tide time: " + secondTideTime.text() + "   " + secondTideHight.text() );
                            System.out.println("third tide time: " + thirdTideTime.text() + "   " + thirdTideHight.text());
                            System.out.println("fourth tide time: " + fourthTideTime.text() + "   " + fourthTideHight.text());
                            {
                                /*
                                                Work with data - all is OK
                                                 */
                        } 
                     } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }      
                return arr_data;//<< return ArrayList from here
            }
             @Override
             protected void onPostExecute(ArrayList<String> result) {
                 mFragmentCallback.onTaskDone();
        }
      }
Thanks for any help.
 
     
     
     
     
    