jsonArray cannot be converted to JSONObject fetch data from mysql to a list view

Question

I am trying to fetch Data from MySql Database to a list view. I am getting one exception JSONArray cannot be converted to JSONObject. Please help me I am new in Android. How I can convert JASONArray to JASONObject. Please help me.

08-19 09:44:43.640: E/JSON(895): {"STATUS":"1","user_id":"92","role":"Clamper","area":"Uptown","street":"Tom Mboya"}
08-19 09:44:44.980: I/Choreographer(895): Skipped 109 frames!  The application may be doing too much work on its main thread.
08-19 09:44:48.200: E/JSON(895): [{"car_no":"MP04","fine_id":"51769","area":"Uptown","street":"Tom Mboya"},{"car_no":"MP09878","fine_id":"51768","area":"Uptown","street":"Tom Mboya"},{"car_no":"MP071256","fine_id":"51767","area":"Uptown","street":"Tom Mboya"},{"car_no":"MP07123","fine_id":"51766","area":"Uptown","street":"Tom Mboya"}]
08-19 09:44:48.530: E/JSON Parser(895): Error parsing data org.json.JSONException:     Value 
[
{"fine_id":"51769"
,"street":"Tom Mboya"
,"area":"Uptown"
,"car_no":"MP04"
},
{"fine_id":"51768"
,"street":"Tom Mboya"
,"area":"Uptown"
,"car_no":"MP09878"
},{"fine_id":"51767","street":"Tom Mboya","area":"Uptown","car_no":"MP071256"}, {"fine_id":"51766","street":"Tom Mboya","area":"Uptown","car_no":"MP07123"}
]
 of type org.json.JSONArray cannot be converted to JSONObject
08-19 09:44:48.530: D/Fetching Response(895): {"role":"Clamper","user_id":"92","area":"Uptown","STATUS":"1","street":"Tom Mboya"}

here my activity code is

public class ClamperActivity extends Activity {

 private ProgressDialog pDialog;
 private ListView list;
 private int success;
 JSONParser jsonParser = new JSONParser();

 public static String user_id="";

 static String url= "http://192.168.1.13/testkrcs/main/get_clamped";

 // JSON Node names
 private static final String TAG_SUCCESS = "success";

  private void minimizeApp()
  {
    Intent localIntent = new Intent("android.intent.action.MAIN");
    localIntent.addCategory("android.intent.category.HOME");
    localIntent.setFlags(268435456);
    startActivity(localIntent);
  }

  public void onBackPressed()
  {
    minimizeApp();
  }

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

    list = (ListView)findViewById(R.id.list);
    new FetchVehiclesTask().execute();

}

class FetchVehiclesTask extends AsyncTask<String, String, String>
{
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(ClamperActivity.this);
        pDialog.setMessage("Fetching Vehicles List...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }

    protected String doInBackground(String... args)
    {
        List<NameValuePair> params = new ArrayList<NameValuePair>();
           params.add(new BasicNameValuePair("street",LoginActivity.street));
           params.add(new BasicNameValuePair("area",LoginActivity.area));
           params.add(new BasicNameValuePair("user_id",LoginActivity.user_id));

            JSONObject json = jsonParser.getJSONFromUrl(url, params);

            Log.d("Fetching Response", json.toString());

               return null;
    }
    protected void onPostExecute(String file_url) {
        // dismiss the dialog once done
        pDialog.dismiss();
    }
}

}

here is my JASONPArser class code

public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) {

    // Making HTTP request
    try {
        // defaultHttpClient
        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);
        httpPost.setEntity(new UrlEncodedFormEntity(params));

        HttpResponse httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        is = httpEntity.getContent();

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                is, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }
        is.close();
        json = sb.toString();
        Log.e("JSON", json);
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }

    // try parse the string to a JSON object
    try {
        jObj = new JSONObject(json);            
    } catch (JSONException e) {
        Log.e("JSON Parser", "Error parsing data " + e.toString());
    }

    // return JSON String
    return jObj;

}

Answer 1

It means you have to change your code to a JSON array to match the data:

Create a new function:

getJSONStringFromUrl

public String getJSONStringFromUrl(String url, List<NameValuePair> params) {
 String json = null;
    // Making HTTP request
    try {
        // defaultHttpClient
        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);
        httpPost.setEntity(new UrlEncodedFormEntity(params));

        HttpResponse httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        is = httpEntity.getContent();

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                is, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }
        is.close();
        json = sb.toString();
        Log.e("JSON", json);
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }

    // return JSON String
    return json;

}

doInBackground

protected String doInBackground(String... args)
{
    List<NameValuePair> params = new ArrayList<NameValuePair>();
    params.add(new BasicNameValuePair("street",LoginActivity.street));
    params.add(new BasicNameValuePair("area",LoginActivity.area));
    params.add(new BasicNameValuePair("user_id",LoginActivity.user_id));
    try {
        String jsonString = jsonParser.getJSONStringFromUrl(url, params);
        JSONObject jsonObj = new JSONObject(jsonString);
        Log.d("Fetching Response", jsonObj.toString());

        String userId jsonObj.getString("user_id");
        Log.d("mylog", "userId = " + userId);      
    } catch (JSONException e) {
            Log.e("JSON Parser", "Error parsing data " + e.toString());
    }

}

Answer 2

Your JSONArray is an array of JSONObject; you should access the elements in your array (loop on your JSONArray) to get your JSONObjects.

I would something like this:

JSONArray jsonA = jsonParser.getJSONFromUrl(url, params);

if (jsonA!=null){
    for (int i=0;i<jsonA.length();i++){
        JSONObject json=jsonA.getJSONObject(i);
       // Deal with each of your JSONObject
    }
}