Cleaning Up Our Presentation. ProgressBar

package com.Arkman.blogreader;

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;
import java.util.ArrayList;
import java.util.HashMap;

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

import android.app.AlertDialog;
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.view.View;
import android.widget.ProgressBar;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import android.widget.Toast;

public class MainListActivity extends ListActivity {


    public static final int NUMBER_OF_POSTS = 20;
    public static final String TAG = MainListActivity.class.getSimpleName();
    protected JSONObject mBlogData;
    protected ProgressBar mProgressBar;

    private final String KEY_TITLE = "title";
    private final String KEY_AUTHOR = "author";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main_list);

        mProgressBar = (ProgressBar) findViewById(R.id.progressBar1);

        if(isNetworkAvailable()){
            mProgressBar.setVisibility(View.VISIBLE);
            GetBlogPostsTask getBlogPostsTask = new GetBlogPostsTask();
            getBlogPostsTask.execute();
        }
        else{
            Toast.makeText(this, "Network is Unavailable!", Toast.LENGTH_LONG).show();
        }
        //Toast.makeText(this, getString(R.string.no_items), 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 handleBlogResponse() {
        mProgressBar.setVisibility(View.INVISIBLE);

        if(mBlogData == null){
            updateDisplayForError();

        }
        else{
            try {
            JSONArray jsonPosts = mBlogData.getJSONArray("posts");
            ArrayList<HashMap<String, String>> blogPosts = 
                    new ArrayList<HashMap<String,String>>();
            for(int i = 0;i<jsonPosts.length();i++){
                JSONObject post = jsonPosts.getJSONObject(i);
                String title = post.getString(KEY_TITLE);
                title = Html.fromHtml(title).toString();
                String author = post.getString(KEY_AUTHOR);
                author = Html.fromHtml(author).toString();

                HashMap<String, String> blogPost = new HashMap<String, String>();
                blogPost.put(KEY_TITLE, title);
                blogPost.put(KEY_AUTHOR, author);


                blogPosts.add(blogPost);
                }
                String[] keys = {KEY_TITLE, KEY_AUTHOR};
                int[] ids = {android.R.id.text1, android.R.id.text2};
                SimpleAdapter adapter = new SimpleAdapter(this,blogPosts,
                        android.R.layout.simple_list_item_2,keys,ids);
                setListAdapter(adapter);
            } catch (JSONException e) {
                Log.e(TAG,"Exception Caught!", e);
            }
        }
    }

    private void updateDisplayForError() {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle(getString(R.string.error_title));
        builder.setMessage(getString(R.string.error_message));
        builder.setPositiveButton(android.R.string.ok, null);
        AlertDialog dialog = builder.create();
        dialog.show();

        TextView emptyTextView = (TextView) getListView().getEmptyView();
        emptyTextView.setText(getString(R.string.no_items));
    }

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

        @Override
        protected JSONObject doInBackground(Object... arg0) {
            int responseCode= -1;
            JSONObject jsonResponse = null;

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

            responseCode= connection.getResponseCode();
            if(responseCode==HttpURLConnection.HTTP_OK){
                InputStream inputStream = connection.getInputStream();
                Reader reader = new InputStreamReader(inputStream);
                int contentLength = connection.getContentLength();
                char[] charArray = new char[contentLength];
                reader.read(charArray);
                String responseData = new String(charArray);

                jsonResponse = new JSONObject(responseData);


            }
            else{
                Log.i(TAG, "Unsecessful HTTP Response Code: " + responseCode);
            }

        } catch (MalformedURLException e) {
            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;
            handleBlogResponse();
        }
    }



}