Only (No items to display) shows when running app.

This is my source code

package com.jerdeez.blogreader;

import android.app.ListActivity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Bundle;
import android.text.Html;
import android.util.Log;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.Toast;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;


public class MainListActivity extends ListActivity {

    protected String[] mBlogPostTitles;
    public static final int NUMBER_OF_POSTS = 20;
    public static final String TAG = MainListActivity.class.getSimpleName();
    protected JSONObject mBlogData;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main_list);
        if (isNetworkAvailable()) {
            GetBlogPostsTask getBlogPostsTask = new GetBlogPostsTask();
            getBlogPostsTask.execute();
            //Toast.makeText(this, getString(R.string.no_items),Toast.LENGTH_LONG).show();
        } else {
            Toast.makeText(this, "Network is unavailable!", Toast.LENGTH_LONG).show();
        }

    }

    private boolean isNetworkAvailable() {
        ConnectivityManager manager = (ConnectivityManager)
                getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = manager.getActiveNetworkInfo();

        boolean isAvailable = false;
        if (networkInfo != null && networkInfo.isConnected()) {
            isAvailable = true;
        }

        return isAvailable;
    }


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

    public void updateList() {
        if (mBlogData == null) {
            //to do: handle error
        }
        else{
            try {
                JSONArray jsonPost = mBlogData.getJSONArray("post");
                mBlogPostTitles = new String[jsonPost.length()];
                for (int i =0; i<jsonPost.length(); i++){
                 JSONObject post = jsonPost.getJSONObject(i);
                 String title = post.getString("title");
                 title = Html.fromHtml(title).toString();
                 mBlogPostTitles [i]= title;
                }
                ArrayAdapter <String> adapter= new ArrayAdapter<String>(this,
                        android.R.layout.simple_list_item_1, mBlogPostTitles);
                        setListAdapter(adapter);
            }
            catch (JSONException e) {
                Log.e(TAG, "Exception Caught!", e);
            }
        }

    }


    private class GetBlogPostsTask extends AsyncTask<Object, Void, JSONObject> {

        @Override
        protected JSONObject doInBackground(Object[] objects) {
            int responseCode = -1;
            JSONObject jsonResponse = null;

            try {
                //URL blogFeedUrl = new URL("http://blog.teamtreehouse.com/api/get_recent_summary/?count =" + NUMBER_OF_POSTS);
                URL blogFeedUrl = new URL("http://blog.teamtreehouse.com/api/get_recent_summary/?count=" + NUMBER_OF_POSTS);
                HttpURLConnection connection = (HttpURLConnection) blogFeedUrl.openConnection();
                connection.connect();

                //Creating are response code so that we can get data from the internet
                responseCode = connection.getResponseCode();
                if (responseCode == HttpURLConnection.HTTP_OK) {
                    InputStream inputStream = connection.getInputStream(); //store the data into the input stream
                    Reader reader = new InputStreamReader(inputStream);//read the input stream
                    int contentLength = connection.getContentLength();//get the number of characters to read in
                    char[] charArray = new char[contentLength];//create the char array to store the the data
                    reader.read(charArray); //read and store the data array into the char array
                    String responseData = new String(charArray);//create a new string and convert and store from char to string

                    //This creates are Json object
                    jsonResponse = new JSONObject(responseData);


                }


                //} else {
                //Log.i(TAG, "Unsuccessful HTTP Response Code: " + responseCode);
                //}
                Log.i(TAG, "Code: " + responseCode);
            } catch (MalformedURLException e) {
                //e.printStackTrace();
                Log.e(TAG, "Exception caught: ", e);
            } catch (IOException e) {
                Log.e(TAG, "Exception caught: ", e);

            } catch (Exception e) {
                Log.e(TAG, "Exception caught: ", e);
            }


            return jsonResponse;
        }

        @Override
        protected void onPostExecute(JSONObject result) {
            mBlogData = result;
            updateList();

        }


    }

}

This is my logcat


10-15 11:25:13.919  32029-32029/com.jerdeez.blogreader W/IInputConnectionWrapper﹕ getSelectedText on inactive InputConnection
10-15 11:25:13.929  32029-32029/com.jerdeez.blogreader W/IInputConnectionWrapper﹕ setComposingText on inactive InputConnection
10-15 11:25:19.039  32029-32029/com.jerdeez.blogreader W/IInputConnectionWrapper﹕ showStatusIcon on inactive InputConnection
10-15 11:25:19.319  32029-32029/com.jerdeez.blogreader I/Adreno200-EGLSUB﹕ <ConfigWindowMatch:2087>: Format RGBA_8888.
10-15 11:25:19.679  32029-32284/com.jerdeez.blogreader I/MainListActivity﹕ Code: 200
10-15 11:25:19.679  32029-32029/com.jerdeez.blogreader E/MainListActivity﹕ Exception Caught!
    org.json.JSONException: No value for post
            at org.json.JSONObject.get(JSONObject.java:354)
            at org.json.JSONObject.getJSONArray(JSONObject.java:544)
            at com.jerdeez.blogreader.MainListActivity.updateList(MainListActivity.java:77)
            at com.jerdeez.blogreader.MainListActivity$GetBlogPostsTask.onPostExecute(MainListActivity.java:148)
            at com.jerdeez.blogreader.MainListActivity$GetBlogPostsTask.onPostExecute(MainListActivity.java:97)
            at android.os.AsyncTask.finish(AsyncTask.java:631)
            at android.os.AsyncTask.access$600(AsyncTask.java:177)
            at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:4781)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:511)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:3152)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:2919)
            at dalvik.system.NativeStart.main(Native Method)