Blog : HttpClient.execute(HttpPost) on Android 4.2 error

HttpClient.execute(HttpPost) on Android 4.2 error
I am following this website http://givemepass.blogspot.hk/2011/12/http-server.html to try to use the android application connect the PHP server to get message.
GetServerMessage.java
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
public class GetServerMessage {

  public String stringQuery(String url){
  try
  {
  HttpClient httpclient = new DefaultHttpClient();
  HttpPost method = new HttpPost(url);
  HttpResponse response = httpclient.execute(method);
  HttpEntity entity = response.getEntity();
  if(entity != null){
  return EntityUtils.toString(entity);
  }
  else{
  return "No string.";
  }
  }
  catch(Exception e){
  return "Network problem";
  }
  }
}
GetPhpServerMessageDemoActivity.java
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;

public class GetPhpServerMessageDemoActivity extends Activity {
  /** Called when the activity is first created. */
  private TextView textView;
  @Override
  public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
  textView = (TextView)findViewById(R.id.text_view);
  GetServerMessage message = new GetServerMessage();
  String msg = message.stringQuery("http://192.168.1.88/androidtesting.php");
  textView.setText("Server message is "+msg);
  }

}
I tried to download the Android Application Project from that sitehttp://uploadingit.com/file/d4632ekfpwjiupyn/GetPhpServerMessageDemo2.zip and run on my phone, it's work. But when I start a new project (Minimuim Requied SDK: API8, Target SDK: API17, Compile with: API17) and copy these two java codes. I've added the permission android.permission.INTERNET, so I don't know where is the problem, I only know that when run HttpResponse response = httpclient.execute(method); there is a error and returned String "Network problem".
You are running network related operation on the ui thread. You will get NetworkOnMainThreadException post honeycomb.
Use a Thread or Asynctask
Invoke asynctask
  new TheTask().execute("http://192.168.1.88/androidtesting.php");
AsyncTask
http://developer.android.com/reference/android/os/AsyncTask.html
class TheTask extends AsyncTask<String,String,String>
  {

@Override
protected String onPostExecute(Void result) {
  // TODO Auto-generated method stub
  super.onPostExecute(result);
  // update textview here
  textView.setText("Server message is "+result);
}

@Override
protected void onPreExecute() {
  // TODO Auto-generated method stub
  super.onPreExecute();
}

@Override
protected String doInBackground(String... params) {
  try
  {
  HttpClient httpclient = new DefaultHttpClient();
  HttpPost method = new HttpPost(params[0]);
  HttpResponse response = httpclient.execute(method);
  HttpEntity entity = response.getEntity();
  if(entity != null){
  return EntityUtils.toString(entity);
  }
  else{
  return "No string.";
  }
  }
  catch(Exception e){
  return "Network problem";
  }

}
}