android เรียก webservice ปตท ไม่ได้ results เป็น null เหมือนเดิม ช่วยหน่อยครับ

package com.example.arkar_000.asas;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.TextView;

import org.ksoap2.SoapEnvelope;
import org.ksoap2.serialization.SoapObject;
import org.ksoap2.serialization.SoapPrimitive;
import org.ksoap2.serialization.SoapSerializationEnvelope;
import org.ksoap2.transport.HttpTransportSE;

import java.util.ArrayList;


public class MyActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my);
        if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment())
                    .commit();
        }
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.my, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public class PlaceholderFragment extends Fragment {



        private Button btnClick;     // activity bottom
        private TextView tView;   // test space text value
        private ArrayAdapter<String> AdapterXML;
        private ArrayList<String> ListitemXML = new ArrayList<String>();
        private SoapPrimitive results = null;    // veriable type SoapPrimitive


        private  String URL = "http://www.pttplc.com/pttinfo.asmx";    // url webservice
        private  String NAMESPACE = "http://www.pttplc.com/ptt_webservice/";  // default value webservice
        private  String METHOD_NAME = "CurrentOilPrice";   // method that request webservice
        private  String SOAP_ACTION = "http://www.pttplc.com/ptt_webservice/CurrentOilPrice";  // use call method webservice

;


        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_my, container, false);

             btnClick = (Button) rootView.findViewById(R.id.button);
             tView = (TextView) rootView.findViewById(R.id.textView1);
             btnClick.setOnClickListener(new View.OnClickListener() {
                 @Override
                 public void onClick(View v) {
                     callWebService();
                 }
             });


            return rootView;

        }

        public void callWebService(){

          Thread s  = new Thread() {
              public void run() {

                      SoapObject callPtt = new SoapObject(NAMESPACE,METHOD_NAME);   // create soapObject
                      callPtt.addProperty("Language", "TH");     //  sent parameter to method webservice


                      SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11 ); // determine format and version of soap
                      envelope.dotNet = true;  // determine dotnet
                      envelope.setOutputSoapObject(callPtt);
                      HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);

                   try{

                      androidHttpTransport.call(SOAP_ACTION, envelope);

                      SoapObject rS = (SoapObject) envelope.bodyIn;
                      String results = rS.toString();  // results in type SoapPrimitive


                  }
                  catch (Exception e) {
                      //  check error
                      results= null;

                  }finally {
                      if (results == null){
                          Log.e("WebServiceExample", "Soap object Error");
                      }
                      else {   // result not null
                          ;

                          goCovert();
                      }
                  }