title: Loading JSON content in fragment
body: <p>I'm very new to Android environment. I was wandering about retrieving JSON content from a web page, so I've found this tutorial to get JSON content from a url (<a href="http://www.learn2crack.com/2013/11/listview-from-json-example.html" rel="nofollow">Tutorial Link</a>) and It works properly also with my data.</p>
  
  <p>Now, <strong>what I wanted to do:</strong> a Tab application, with one of these tabs using that code to retrieve JSON data. I've used fragment and I tried to modify code in order to be compatible with fragments, anyway as I start the related tab, the application crashes.</p>
  
  <p>As the previous tutorial works properly, I'm pretty sure the problem is on my newbie code. </p>
  
  <p><strong>FragmentTab1.Java</strong></p>
  
  <pre><code>package com.alessandrobocci.fenice;
  import java.util.ArrayList;
  import java.util.HashMap;
  import com.alessandrobocci.fenice.library.JSONParser;
  import org.json.JSONArray;
  import org.json.JSONException;
  import org.json.JSONObject;
  import android.app.Fragment;
  import android.app.ProgressDialog;
  import android.os.AsyncTask;
  import android.os.Bundle;
  import android.view.LayoutInflater;
  import android.view.View;
  import android.view.ViewGroup;
  import android.widget.AdapterView;
  import android.widget.Button;
  import android.widget.ListAdapter;
  import android.widget.ListView;
  import android.widget.SimpleAdapter;
  import android.widget.TextView;
  import android.widget.Toast;
  
  
  public class FragmentTab1 extends Fragment {
      ListView list;
      TextView title;
      TextView name;
      TextView api;
      Button Btngetdata;
      ArrayList&lt;HashMap&lt;String, String&gt;&gt; oslist = new ArrayList&lt;HashMap&lt;String, String&gt;&gt;();
  
      //URL to get JSON Array
      private static String url = "http://10.0.2.2/test/read.php";
  
      //JSON Node Names 
      private static final String TAG_OS = "todo";
      private static final String TAG_VER = "title";
  
      JSONArray arr = null;
      public View onCreateView(LayoutInflater inflater, ViewGroup container,
              Bundle savedInstanceState) {
          //Inflate the layout for this fragment
          //This layout contains your list view 
          View view = inflater.inflate(R.layout.fragmenttab1, container, false);
          title = (TextView)getView().findViewById(R.id.vers);
          //now you must initialize your list view
          list =(ListView)view.findViewById(R.id.listnews);
          new JSONParse().execute();
  
          return view;
      }
      private class JSONParse extends AsyncTask&lt;String, String, JSONObject&gt; {
       private ProgressDialog pDialog;
      @Override
         protected void onPreExecute() {
             super.onPreExecute();
             pDialog = new ProgressDialog(getActivity());
             pDialog.setMessage("Getting Data ...");
             pDialog.setIndeterminate(false);
             pDialog.setCancelable(true);
             pDialog.show();            
      }
  
      @Override
         protected JSONObject doInBackground(String... args) {
  
          JSONParser jParser = new JSONParser();
          // Getting JSON from URL
          JSONObject json = jParser.getJSONFromUrl(url);
          return json;
      }
       @Override
      protected void onPostExecute(JSONObject json) {
           pDialog.dismiss();
           try {
              // Getting JSON Array from URL
              arr = json.getJSONArray(TAG_OS);
              for(int i = 0; i &lt; arr.length(); i++){
              JSONObject c = arr.getJSONObject(i);
              // Storing  JSON item in a Variable
              String ver = c.getString(TAG_VER);
              // Adding value HashMap key =&gt; value
              HashMap&lt;String, String&gt; map = new HashMap&lt;String, String&gt;();
              map.put(TAG_VER, ver);
              oslist.add(map);
              //list=(ListView) getView().findViewById(R.id.list);
              ListAdapter adapter = new SimpleAdapter(getActivity(), oslist,
                  R.layout.list_v,
                  new String[] { TAG_VER }, new int[] {
                      R.id.vers});
              list.setAdapter(adapter);
              list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                      @Override
                      public void onItemClick(AdapterView&lt;?&gt; parent, View view,
                                              int position, long id) {
                          Toast.makeText(getActivity(), "You Clicked at "+oslist.get(+position).get("title"), Toast.LENGTH_SHORT).show();
                      }
                  });
              }
          } catch (JSONException e) {
            e.printStackTrace();
          }
         }
     }
  }
  </code></pre>
  
  <p>logCat:</p>
  
  <pre><code>07-04 14:59:36.250: D/gralloc_goldfish(1081): Emulator without GPU emulation detected.
  07-04 14:59:38.350: D/dalvikvm(1081): GC_CONCURRENT freed 154K, 10% free 6030K/6663K, paused 11ms+8ms
  07-04 14:59:38.690: W/System.err(1081): org.apache.http.conn.HttpHostConnectException: Connection to http://10.0.2.2 refused
  07-04 14:59:38.741: W/System.err(1081):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:183)
  07-04 14:59:38.741: W/System.err(1081):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
  07-04 14:59:38.881: W/System.err(1081):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
  07-04 14:59:38.910: W/System.err(1081):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
  07-04 14:59:38.910: W/System.err(1081):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
  07-04 14:59:39.100: W/System.err(1081):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
  07-04 14:59:39.150: W/System.err(1081):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
  07-04 14:59:39.150: W/System.err(1081):     at com.alessandrobocci.fenice.library.JSONParser.getJSONFromUrl(JSONParser.java:38)
  07-04 14:59:39.200: W/System.err(1081):     at com.alessandrobocci.fenice.FragmentTab1$JSONParse.doInBackground(FragmentTab1.java:72)
  07-04 14:59:39.310: W/System.err(1081):     at com.alessandrobocci.fenice.FragmentTab1$JSONParse.doInBackground(FragmentTab1.java:1)
  07-04 14:59:39.330: W/System.err(1081):     at android.os.AsyncTask$2.call(AsyncTask.java:264)
  07-04 14:59:39.330: W/System.err(1081):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
  07-04 14:59:39.390: W/System.err(1081):     at java.util.concurrent.FutureTask.run(FutureTask.java:137)
  07-04 14:59:39.440: W/System.err(1081):     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
  07-04 14:59:39.440: W/System.err(1081):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
  07-04 14:59:39.500: W/System.err(1081):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
  07-04 14:59:39.510: W/System.err(1081):     at java.lang.Thread.run(Thread.java:856)
  07-04 14:59:39.510: W/System.err(1081): Caused by: java.net.ConnectException: socket failed: EACCES (Permission denied)
  07-04 14:59:39.611: W/System.err(1081):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:181)
  07-04 14:59:39.710: W/System.err(1081):     ... 16 more
  07-04 14:59:39.710: W/System.err(1081): Caused by: java.net.SocketException: socket failed: EACCES (Permission denied)
  07-04 14:59:39.870: W/System.err(1081):     at libcore.io.IoBridge.socket(IoBridge.java:573)
  07-04 14:59:39.870: W/System.err(1081):     at java.net.PlainSocketImpl.create(PlainSocketImpl.java:201)
  07-04 14:59:39.870: W/System.err(1081):     at java.net.Socket.checkOpenAndCreate(Socket.java:663)
  07-04 14:59:39.921: W/System.err(1081):     at java.net.Socket.connect(Socket.java:807)
  07-04 14:59:39.979: W/System.err(1081):     at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:119)
  07-04 14:59:39.979: W/System.err(1081):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144)
  07-04 14:59:40.051: W/System.err(1081):     ... 16 more
  07-04 14:59:40.091: W/System.err(1081): Caused by: libcore.io.ErrnoException: socket failed: EACCES (Permission denied)
  07-04 14:59:40.210: W/System.err(1081):     at libcore.io.Posix.socket(Native Method)
  07-04 14:59:40.240: W/System.err(1081):     at libcore.io.BlockGuardOs.socket(BlockGuardOs.java:169)
  07-04 14:59:40.260: W/System.err(1081):     at libcore.io.IoBridge.socket(IoBridge.java:558)
  07-04 14:59:40.310: W/System.err(1081):     ... 21 more
  07-04 14:59:40.370: E/Buffer Error(1081): Error converting result java.lang.NullPointerException
  07-04 14:59:40.380: E/JSON Parser(1081): Error parsing data org.json.JSONException: End of input at character 0 of 
  07-04 14:59:40.390: D/AndroidRuntime(1081): Shutting down VM
  07-04 14:59:40.403: W/dalvikvm(1081): threadid=1: thread exiting with uncaught exception (group=0x409951f8)
  07-04 14:59:40.452: E/AndroidRuntime(1081): FATAL EXCEPTION: main
  07-04 14:59:40.452: E/AndroidRuntime(1081): java.lang.NullPointerException
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at com.alessandrobocci.fenice.FragmentTab1$JSONParse.onPostExecute(FragmentTab1.java:80)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at com.alessandrobocci.fenice.FragmentTab1$JSONParse.onPostExecute(FragmentTab1.java:1)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at android.os.AsyncTask.finish(AsyncTask.java:602)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at android.os.AsyncTask.access$600(AsyncTask.java:156)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:615)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at android.os.Handler.dispatchMessage(Handler.java:99)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at android.os.Looper.loop(Looper.java:137)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at android.app.ActivityThread.main(ActivityThread.java:4340)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at java.lang.reflect.Method.invokeNative(Native Method)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at java.lang.reflect.Method.invoke(Method.java:511)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
  07-04 14:59:40.452: E/AndroidRuntime(1081):     at dalvik.system.NativeStart.main(Native Method)
  </code></pre>
  
  <p>If necessary, I'll post also the other code, I don't think anyway it's useful, as for example MainActivity.Java (who contains Tabs) works with simple FragmenTab code that retrieves some text.
  Hope I was clear, thanks.</p>