Java 从数据库[phpmyadmin]填充的多级listview

我已经在一个由远程数据库填充的多级listview上工作了将近一周，但我仍然无法解决listview第二级的错误

以下是错误：

org.json.JSONException: No value for id
at org.json.JSONObject.get(JSONObject.java:354)

但它已经返回了我试图检索的正确数据

{"success":1,"message":"Patient Available","post":[{"id":"29","date":"2014-02-06 21:15:29","description":"Healthy"}]}

这是我的第二级java类

History.java

    private Button create;
private ProgressDialog pDialog;
private static final String READ_HISTORY_URL = "http://192.168.43.15:8080/DoctorScheduler/activities/history.php";

private static final String TAG_POST    = "post";
private static final String TAG_DATE    = "date";
private static final String TAG_DESC    = "description";
private static final String TAG_ID      = "id";

JSONParser jsonParser = new JSONParser();
JSONArray history = null;
String patient_id , remarks_id;
ArrayList<HashMap<String, String>> historyList;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_history);

    //get patient_id
    Intent i = getIntent();
    patient_id = i.getStringExtra("id");

    //hashmap for history listview
    historyList = new ArrayList<HashMap<String, String>>();

    new LoadHistory().execute();

    ListView lv = getListView();
    lv.setOnItemClickListener(new OnItemClickListener(){

        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position,
                long id) {
            // TODO Auto-generated method stub

            // INSERT ALL PREVIOUS CONSULTATIONS OF THE PATIENT HERE
            Intent viewhistory = new Intent(History.this, Singlehistory.class);

            String patient_id = ((TextView) view.findViewById(R.id.txtPid)).getText().toString();
            String remarks_id = ((TextView) view.findViewById(R.id.txtRid)).getText().toString();

            Toast.makeText(getApplicationContext(), "p_id: " + patient_id + ", r_id: " + remarks_id, Toast.LENGTH_LONG).show();

            viewhistory.putExtra("patient_id", patient_id);
            viewhistory.putExtra("remarks_id", remarks_id);

            startActivity(viewhistory);
        }
    });

    create = (Button) findViewById(R.id.BtnNew);
    create.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

            Intent createInfo = new Intent(History.this, Addhistory.class);
            startActivity(createInfo);
        }
    });

}

class LoadHistory extends AsyncTask<String, String, String> {

    @Override
    protected void onPreExecute() {
        // TODO Auto-generated method stub
        super.onPreExecute();

        pDialog = new ProgressDialog(History.this);
        pDialog.setMessage("Loading all patient consultations....");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show(); 

    }

    @Override
    protected String doInBackground(String... args) {
        // TODO Auto-generated method stub
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("id", patient_id));

        String json = jsonParser.getJSONFromURL(READ_HISTORY_URL, "GET", params);

        Log.d("Response: ", json);

        try{
            JSONObject jObj = new JSONObject(json);

            if(jObj!=null){

                String patient_id = jObj.getString(TAG_ID);
                history = jObj.getJSONArray(TAG_POST);

                if(history != null){
                    //looping through all patient's remarks
                    for(int i=0; i<history.length(); i++){
                    JSONObject c = history.getJSONObject(i);

                        //storing into json variable

                        String remarks_id = c.getString(TAG_ID);
                        String date = c.getString(TAG_DATE);
                        String description = c.getString(TAG_DESC);

                        //creating new HashMap
                        HashMap<String, String> map = new HashMap<String, String>();
                        map.put("patient_id", patient_id);
                        map.put(TAG_ID, remarks_id);
                        map.put(TAG_DATE, date);
                        map.put(TAG_DESC, description);

                        historyList.add(map);
                    }
                }else{
                    Log.d("History:", "null");
                }
            }
        }catch(JSONException e){
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(String result) {
        // TODO Auto-generated method stub
        //super.onPostExecute(result);
        pDialog.dismiss();

        ListAdapter adapter = new SimpleAdapter(
                History.this, historyList,  R.layout.mainhistory,
                new String[] {"patient_id", "TAG_ID", TAG_DATE, TAG_DESC},
                new int[] {R.id.txtPid, R.id.txtRid, R.id.txtRdate, R.id.txtRdesc});

        setListAdapter(adapter);
    }
}

我对listview的第一级没有问题，但是每当我试图检索我在第一个listview中单击的患者的所有备注时，它在第二个listview中不会显示任何内容

$query = "SELECT * FROM remarks WHERE patient_id = :id";
$query_params = array(':id' => $_GET['id']);    

try{
    $stmt = $dbname->prepare($query);
    $result = $stmt->execute($query_params);    

    $id = $_GET["id"];

    // check if p.patient_id = r.patient_id ($remarks' patient_id)

    $query = "SELECT date, description FROM remarks WHERE patient_id = $id";

    $q = $dbname->prepare($query); 
    $q->execute();


}catch(PDOException $ex){
        $response["success"] = 0;
        $response["message"] = $ex;

        die(json_encode($response));
    }

//retrieve all the rows
$rows = $stmt->fetchAll();

if($rows){
    $response["success"] = 1;
    $response["message"] = "Patient Available";
    $response["post"] = array();

    foreach($rows as $row){
        $post               = array();
        $post["id"]         = $row["patient_id"];
        $post["date"]       = $row["date"];
        $post["description"]= $row["description"];

        //update json response
        array_push($response["post"], $post);
        }

    echo json_encode($response);
}
else{
    $response["success"] = 0;
    $response["message"] = "No available patient's record";

    die(json_encode($response));

}