Próbuję wyświetlić listę wszystkich kontaktów w telefonie komórkowym. Do tej pory wszystko działało dobrze, ale kiedy pomyślałem o uruchomieniu mojego koduAsyncTask Nic nie mam na ekranie.

Oto fragment kodu

protected void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_call_list);

    lvCallList = (ListView) findViewById(R.id.lv_call_list);

    new AsyncTask<Void, Void, Void>() 
    {
        @Override
        protected void onPreExecute() 
        {
            pd = ProgressDialog.show(CallListActivity.this,
                    "Loading..", "Please Wait", true, false);
        }// End of onPreExecute method

        @Override
        protected Void doInBackground(Void... params) 
        {
            getContacts();

            return null;
        }// End of doInBackground method

        @Override
        protected void onPostExecute(Void result)
        {
            pd.dismiss();

            lvCallList.setAdapter(new CustomAdapter(CallListActivity.this));

        }//End of onPostExecute method
    }.execute((Void[]) null);
     count = this.displayContactName.size();
    thumbnailsselection = new boolean[count];
}


private void getContacts()
{
    ContentResolver cr = getContentResolver();
    Cursor cur = cr.query(ContactsContract.Contacts.CONTENT_URI, null,null, null, null);
    if (cur.getCount() > 0)
    {
        while (cur.moveToNext())
        {
            String id = cur.getString(cur.getColumnIndex(ContactsContract.Contacts._ID));
            String name = cur.getString(cur.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));

            this.displayContactName.add(name);
            if (Integer.parseInt(cur.getString(cur.getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER))) > 0)
            {
                Cursor pCur = cr.query( ContactsContract.CommonDataKinds.Phone.CONTENT_URI,
                                        null,
                                        ContactsContract.CommonDataKinds.Phone.CONTACT_ID +" = ?", 
                                        new String[]{id}, 
                                        null);
                while (pCur.moveToNext())
                {
                    String phoneNumber = pCur.getString(pCur.getColumnIndex( ContactsContract.CommonDataKinds.Phone.NUMBER));
                    this.displayContactNumber.add(phoneNumber);
                } 
                pCur.close();
            }
        }
    }
}

 public class CustomAdapter extends BaseAdapter 
{
    /*
     * Variables Declaration section
     */
    private Context mContext;

    public CustomAdapter(Context context) 
    {
        mContext = context;
    }//End of CustomAdapter constructor

    public int getCount() 
    {
        return count;
    }//End of getCount method

    public Object getItem(int position) 
    {
        return position;
    }//End of getItem method

    public long getItemId(int position) 
    {
        return position;
    }//End of getItemId method

    public View getView(int position, View convertView, ViewGroup parent) 
    {

        return convertView;
    }//End of getView method
}//End of CustomAdapter instance inner class

class ViewHolder 
{
    TextView textviewName;
    TextView textviewNumber;
    CheckBox checkbox;
    int id;
}//End of ViewHolder instance inner class

displayContactName wartość za pomocą punktu przerwania wpd.dismiss(); jest

displayContactName  ArrayList  (id=830007844896)    
array   Object[12]  (id=830007907208)   
    [0] "Rrs" (id=830007907144) 
    [1] "Fgsd" (id=830007920424)    
    [2] null    
    [3] null    
    [4] null    
    [5] null    
    [6] null    
    [7] null    
    [8] null    
    [9] null    
    [10]    null    
    [11]    null    
modCount    2   
size    2   

Nie wiem, co jest nie tak w moim kodzie, gdy go nie używamAsyncTask wtedy mój kod działa doskonale, ale kiedy używamAsyncTask problem. Pomóż mi rozwiązać tę zagadkę.

Z góry dziękuję.