Помогите с загрузкой изображений на андроид

сделал по примеру загрузку с сервера через listview но приложение отказывается загружать изображение по нажатию.

package com.myapp;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.HashMap;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;


public class MainActivity extends Activity  {

    private ListView lstView;
    private ImageAdapter imageAdapter;
    private Handler handler = new Handler();;

    ArrayList<HashMap<String, Object>> MyArrList = new ArrayList<HashMap<String, Object>>();

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);        

        // ProgressBar
        requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);

        setContentView(R.layout.activity_main);

        // ListView and imageAdapter
        lstView = (ListView) findViewById(R.id.listView1);
        lstView.setClipToPadding(false);
        imageAdapter = new ImageAdapter(getApplicationContext()); 
        lstView.setAdapter(imageAdapter);


        // OnClick
        lstView.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View v,
                int position, long id) {
                startDownload(position);
            }
        });

        new LoadContentFromServer().execute();

    }


    //Download
    public void startDownload(final int position) {     

        Runnable runnable = new Runnable() {
            int Status = 0;

            public void run() {

                String urlDownload = MyArrList.get(position).get("ImagePathFull").toString();
                int count = 0;
                try {

                    URL url = new URL(urlDownload);
                    URLConnection conexion = url.openConnection();
                    conexion.connect();

                    int lenghtOfFile = conexion.getContentLength();
                    Log.d("ANDRO_ASYNC", "Lenght of file: " + lenghtOfFile);

                    InputStream input = new BufferedInputStream(url.openStream());

                    // Get File Name from URL
                    String fileName = urlDownload.substring(urlDownload.lastIndexOf('/')+1, urlDownload.length() );

                    OutputStream output = new FileOutputStream("/mnt/sdcard/mydata/"+fileName);

                    byte data[] = new byte[1024];
                    long total = 0;

                        while ((count = input.read(data)) != -1) {
                            total += count;
                            Status = (int)((total*100)/lenghtOfFile);
                            output.write(data, 0, count);

                            // Update ProgressBar
                            handler.post(new Runnable() {
                                public void run() {
                                    updateStatus(position,Status);  
                                }
                            });

                        }

                        output.flush();
                        output.close();
                        input.close(); 

                    } catch (Exception e) {}


            }
        };
        new Thread(runnable).start();
    }

    private void updateStatus(int index,int Status){

        View v = lstView.getChildAt(index - lstView.getFirstVisiblePosition());

        // Update ProgressBar
        ProgressBar progress = (ProgressBar)v.findViewById(R.id.progressBar);
        progress.setProgress(Status);

    }



    class LoadContentFromServer extends AsyncTask<Object, Integer, Object> {

        protected void onPreExecute() {
            super.onPreExecute();
            setProgressBarIndeterminateVisibility(true); 
        }

        @Override
        protected Object doInBackground(Object... params) {


            /** JSON from URL
             * [
             * {"ImageID":"1","ImageName":"Image 1","ImagePath_Thumbnail":"http://www.thaicreate.com/android/img1_thum.jpg" ,"ImagePath_FullPhoto":"http://www.thaicreate.com/android/img1_full.jpg"},
             * {"ImageID":"2","ImageName":"Image 2","ImagePath_Thumbnail":"http://www.thaicreate.com/android/img2_thum.jpg" ,"ImagePath_FullPhoto":"http://www.thaicreate.com/android/img2_full.jpg"},
             * {"ImageID":"3","ImageName":"Image 3","ImagePath_Thumbnail":"http://www.thaicreate.com/android/img3_thum.jpg" ,"ImagePath_FullPhoto":"http://www.thaicreate.com/android/img3_full.jpg"},
             * {"ImageID":"4","ImageName":"Image 4","ImagePath_Thumbnail":"http://www.thaicreate.com/android/img4_thum.jpg" ,"ImagePath_FullPhoto":"http://www.thaicreate.com/android/img4_full.jpg"},
             * {"ImageID":"5","ImageName":"Image 5","ImagePath_Thumbnail":"http://www.thaicreate.com/android/img5_thum.jpg" ,"ImagePath_FullPhoto":"http://www.thaicreate.com/android/img5_full.jpg"},
             * {"ImageID":"6","ImageName":"Image 6","ImagePath_Thumbnail":"http://www.thaicreate.com/android/img6_thum.jpg" ,"ImagePath_FullPhoto":"http://www.thaicreate.com/android/img6_full.jpg"}
             * ]
             */

            String url = "http://www.thaicreate.com/android/getJSON.php";

            JSONArray data;
            try {
                data = new JSONArray(getJSONUrl(url));

                MyArrList = new ArrayList<HashMap<String, Object>>();
                HashMap<String, Object> map;

                for(int i = 0; i < data.length(); i++){
                    JSONObject c = data.getJSONObject(i);
                    map = new HashMap<String, Object>();
                    map.put("ImageID", (String)c.getString("ImageID"));
                    map.put("ImageName", (String)c.getString("ImageName"));

                    // Thumbnail Get ImageBitmap To Object
                    map.put("ImagePathThum", (String)c.getString("ImagePath_Thumbnail"));
                    map.put("ImageThumBitmap", (Bitmap)loadBitmap(c.getString("ImagePath_Thumbnail")));

                    // Full (for View Popup)
                    map.put("ImagePathFull", (String)c.getString("ImagePath_FullPhoto"));

                    MyArrList.add(map);
                    publishProgress(i);
                }

            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return null;
        }

        @Override
        public void onProgressUpdate(Integer... progress) {
            imageAdapter.notifyDataSetChanged();
        }

        @Override
        protected void onPostExecute(Object result) {
            setProgressBarIndeterminateVisibility(false); 
        }
    }   


    class ImageAdapter extends BaseAdapter {

        private Context mContext; 

        public ImageAdapter(Context context) { 
            mContext = context; 
        } 

        public int getCount() { 
            return MyArrList.size();    
        } 

        public Object getItem(int position) { 
            return MyArrList.get(position); 
        } 

        public long getItemId(int position) { 
            return position; 
        } 

        public View getView(final int position, View convertView, ViewGroup parent) {
            // TODO Auto-generated method stub

            LayoutInflater inflater = (LayoutInflater) mContext
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);


            if (convertView == null) {
                convertView = inflater.inflate(R.layout.activity_column, null); 
            }

            // ColImage
            ImageView imageView = (ImageView) convertView.findViewById(R.id.ColImgPath);
            imageView.getLayoutParams().height = 80;
            imageView.getLayoutParams().width = 80;
            imageView.setPadding(10, 10, 10, 10);
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
             try
             {
                 imageView.setImageBitmap((Bitmap)MyArrList.get(position).get("ImageThumBitmap"));
             } catch (Exception e) {
                 // When Error
                 imageView.setImageResource(android.R.drawable.ic_menu_report_image);
             }

            // ColImgID
            TextView txtImgID = (TextView) convertView.findViewById(R.id.ColImgID);
            txtImgID.setPadding(10, 0, 0, 0);
            txtImgID.setText("ID : " + MyArrList.get(position).get("ImageID").toString());

            // ColImgName
            TextView txtPicName = (TextView) convertView.findViewById(R.id.ColImgName);
            txtPicName.setPadding(10, 0, 0, 0);
            txtPicName.setText("Name : " + MyArrList.get(position).get("ImageName").toString());    


            // progressBar
            ProgressBar progress = (ProgressBar) convertView.findViewById(R.id.progressBar);
            progress.setPadding(10, 0, 10, 0);

            return convertView;

        }

    }


    /***** Get Image Resource from URL (Start) *****/
    private static final String TAG = "Image";
    private static final int IO_BUFFER_SIZE = 4 * 1024;
    public static Bitmap loadBitmap(String url) {
        Bitmap bitmap = null;
        InputStream in = null;
        BufferedOutputStream out = null;

        try {
            in = new BufferedInputStream(new URL(url).openStream(), IO_BUFFER_SIZE);

            final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
            out = new BufferedOutputStream(dataStream, IO_BUFFER_SIZE);
            copy(in, out);
            out.flush();

            final byte[] data = dataStream.toByteArray();
            BitmapFactory.Options options = new BitmapFactory.Options();
            //options.inSampleSize = 1;

            bitmap = BitmapFactory.decodeByteArray(data, 0, data.length,options);
        } catch (IOException e) {
            Log.e(TAG, "Could not load Bitmap from: " + url);
        } finally {
            closeStream(in);
            closeStream(out);
        }

        return bitmap;
    }

     private static void closeStream(Closeable stream) {
            if (stream != null) {
                try {
                    stream.close();
                } catch (IOException e) {
                    android.util.Log.e(TAG, "Could not close stream", e);
                }
            }
        }

     private static void copy(InputStream in, OutputStream out) throws IOException {
        byte[] b = new byte[IO_BUFFER_SIZE];
        int read;
        while ((read = in.read(b)) != -1) {
            out.write(b, 0, read);
        }
    }
    /***** Get Image Resource from URL (End) *****/


        /*** Get JSON Code from URL ***/
        public String getJSONUrl(String url) {
            StringBuilder str = new StringBuilder();
            HttpClient client = new DefaultHttpClient();
            HttpGet httpGet = new HttpGet(url);
            try {
                HttpResponse response = client.execute(httpGet);
                StatusLine statusLine = response.getStatusLine();
                int statusCode = statusLine.getStatusCode();
                if (statusCode == 200) { // Download OK
                    HttpEntity entity = response.getEntity();
                    InputStream content = entity.getContent();
                    BufferedReader reader = new BufferedReader(new InputStreamReader(content));
                    String line;
                    while ((line = reader.readLine()) != null) {
                        str.append(line);
                    }
                } else {
                    Log.e("Log", "Failed to download file..");
                }
            } catch (ClientProtocolException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str.toString();
        }

}

<?php
    $objConnect = mysql_connect("localhost","root","root");
    $objDB = mysql_select_db("mydatabase");

    $strSQL = "SELECT * FROM images WHERE 1  ";
    $objQuery = mysql_query($strSQL);
    $intNumField = mysql_num_fields($objQuery);
    $resultArray = array();
    while($obResult = mysql_fetch_array($objQuery))
    {
        $arrCol = array();
        for($i=0;$i<$intNumField;$i++)
        {
            $arrCol[mysql_field_name($objQuery,$i)] = $obResult[$i];
        }
        array_push($resultArray,$arrCol);
    }

    mysql_close($objConnect);

    echo json_encode($resultArray);
?>