Estou tentando exibir o resultado JSON do link de URL JSON. Atualmente, quando carrego, ele não exibe nada, apenas página em branco.Esta é a fonte onde obtive informações sobre JSON.

Este é o meu código:

public class DVLAresult extends AppCompatActivity {


    public class DVLAlist extends ListActivity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {

            super.onCreate(savedInstanceState);
            setContentView(R.layout.content_dvlaresult);


            setListAdapter(new ArrayAdapter(
                    this,android.R.layout.simple_list_item_2,
                    this.populate()));
        }


        private ArrayList<String> populate() {
            ArrayList<String> items = new ArrayList<String>();

            TextView newtext = (TextView) findViewById(R.id.view_number);

            try {
                URL url = new URL
                        ("https://dvlasearch.appspot.com/DvlaSearch?licencePlate=mt09nks&apikey=DvlaSearchDemoAccount");
                HttpURLConnection urlConnection =
                        (HttpURLConnection) url.openConnection();
                urlConnection.setRequestMethod("GET");
                urlConnection.connect();
                // gets the server json data
                BufferedReader bufferedReader =
                        new BufferedReader(new InputStreamReader(
                                urlConnection.getInputStream()));
                String next;
                while ((next = bufferedReader.readLine()) != null) {
                    JSONArray ja = new JSONArray(next);

                    for (int i = 0; i < ja.length(); i++) {
                        JSONObject jo = (JSONObject) ja.get(i);
                        items.add(jo.getString("text"));
                    }
                }
            } catch (MalformedURLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return items;
        }
    }
}

E este é o meu arquivo XML simple_list_2.xml

<?xml version="1.0" encoding="utf-8"?>

<TwoLineListItem xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:minHeight="?attr/listPreferredItemHeight"
    android:mode="twoLine"
    android:paddingStart="?attr/listPreferredItemPaddingStart"
    android:paddingEnd="?attr/listPreferredItemPaddingEnd">

    <TextView android:id="@id/text1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:textAppearance="?attr/textAppearanceListItem" />

    <TextView android:id="@id/text2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/text1"
        android:layout_alignStart="@id/text1"
        android:textAppearance="?attr/textAppearanceListItemSecondary" />

    <TextView android:id="@id/text3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/text2"
        android:layout_alignStart="@id/text2"
        android:textAppearance="?attr/textAppearanceListItemSecondary" />

... Continue up to text18, because I have 18 fields.

</TwoLineListItem>

E este é o principal XML ListView

 <ListView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/list"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:layout_above="@+id/button2"
        android:layout_below="@+id/view_number" />