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Use ListActivity inside a Fragment

Here are two codes that I wanted to combine and make it work, I have this navigation drawer which I wanted to put my post comment post inside and enable it to run.

To enable it to run, I will need to make the listActivity runs inside a fragments. It's not possible to extend two activities, so I would like the community to take a look at my code if it can be connect and make it works. This code I got it online.

The HomeFragment.java

import android.app.Fragment;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;


public class HomeFragment extends Fragment {

public HomeFragment() {
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragment_home, container,
            false);

    return rootView;

}

ReadComments.java

import java.util.ArrayList;
import java.util.HashMap;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;


import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class ReadComments extends ListActivity {



private static final String READ_COMMENTS_URL = "http://www.xxxx.com/webservice/comments.php";
private static final String TAG_MESSAGE = "message";
private static final String TAG_POSTS = "posts";
private static final String TAG_POST_ID = "post_id";
private static final String TAG_SUCCESS = "success";
private static final String TAG_TITLE = "title";
private static final String TAG_USERNAME = "username";

private JSONArray mComments = null;
private ArrayList<HashMap<String, String>> mCommentList;
private ProgressDialog pDialog;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // note that use read_comments.xml instead of our single_post.xml
    setContentView(R.layout.fragment_home);
}

@Override
protected void onResume() {
    // TODO Auto-generated method stub
    super.onResume();
    // loading the comments via AsyncTask
    new LoadComments().execute();
}

public void addComment(View v) {
    Intent i = new Intent(ReadComments.this, AddComment.class);
    startActivity(i);
}

/**
 * Retrieves recent post data from the server.
 */
public void updateJSONdata() {

    // Instantiate the arraylist to contain all the JSON data.
    // we are going to use a bunch of key-value pairs, referring
    // to the json element name, and the content, for example,
    // message it the tag, and "I'm awesome" as the content..

    mCommentList = new ArrayList<HashMap<String, String>>();

    // Bro, it's time to power up the J parser
    JSONParser jParser = new JSONParser();
    // Feed the beast our comments url, and it spits us
    // back a JSON object. Boo-yeah Jerome.
    JSONObject json = jParser.getJSONFromUrl(READ_COMMENTS_URL);

    // when parsing JSON stuff, we should probably
    // try to catch any exceptions:
    try {

        // I know I said we would check if "Posts were Avail." (success==1)
        // before we tried to read the individual posts, but I lied...
        // mComments will tell us how many "posts" or comments are
        // available
        mComments = json.getJSONArray(TAG_POSTS);

        // looping through all posts according to the json object returned
        for (int i = 0; i < mComments.length(); i++) {
            JSONObject c = mComments.getJSONObject(i);

            // gets the content of each tag
            String title = c.getString(TAG_TITLE);
            String content = c.getString(TAG_MESSAGE);
            String username = c.getString(TAG_USERNAME);

            // creating new HashMap
            HashMap<String, String> map = new HashMap<String, String>();

            map.put(TAG_TITLE, title);
            map.put(TAG_MESSAGE, content);
            map.put(TAG_USERNAME, username);

            // adding HashList to ArrayList
            mCommentList.add(map);

            // annndddd, our JSON data is up to date same with our array
            // list
        }

    } catch (JSONException e) {
        e.printStackTrace();
    }
}

/**
 * Inserts the parsed data into the listview.
 */
private void updateList() {

    ListAdapter adapter = new SimpleAdapter(this, mCommentList,
            R.layout.single_post, new String[] { TAG_TITLE, TAG_MESSAGE,
                    TAG_USERNAME }, new int[] { R.id.title, R.id.message,
                    R.id.username });

    // I shouldn't have to comment on this one:
    setListAdapter(adapter);
    ListView lv = getListView();    
    lv.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {

        }
    });
}

public class LoadComments extends AsyncTask<Void, Void, Boolean> {

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(ReadComments.this);
        pDialog.setMessage("Loading Comments...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }

    @Override
    protected Boolean doInBackground(Void... arg0) {
        updateJSONdata();
        return null;

    }

    @Override
    protected void onPostExecute(Boolean result) {
        super.onPostExecute(result);
        pDialog.dismiss();
        updateList();
    }
  }
}

Use a ListFragment for this, you can find the documentation and reference here: http://developer.android.com/reference/android/app/ListFragment.html

you can google examples (eg: http://www.vogella.com/tutorials/AndroidListView/article.html#listactivity )

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