从Url执行Xml Parsing应用程序时，listview中没有显示任何内容

Question

这是我的代码。在给出Internet权限的情况下执行时未显示任何内容。 但它并没有给任何力量关闭错误

public class MainActivity extends Activity {

private ListView listView;

 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  listView = (ListView) findViewById(R.id.listview);
  bindDataToListing();
 }

 private void bindDataToListing() {
  try {
   SAXParserFactory saxparser = SAXParserFactory.newInstance();
   SAXParser parser = saxparser.newSAXParser();
   XMLReader xmlReader = parser.getXMLReader();
   ParsingClass pc = new ParsingClass();
   xmlReader.setContentHandler(pc);


   URL url = new URL("https://222.165.187.91/ex_rate/XML_LOLC_EXRT.xml");
   URLConnection connection = url.openConnection();
   HttpURLConnection httpConn = (HttpURLConnection)connection;
   httpConn.setDoInput(true);
   httpConn.setRequestProperty("charset", "utf-8");
   int responseCode = httpConn.getResponseCode();
   if(responseCode != HttpStatus.SC_OK) {
       InputStream xmlStream = httpConn.getInputStream();
   xmlReader.parse(new InputSource(xmlStream));
   BindingData bindingData = new BindingData(this,pc.date, pc.from_currency,pc.to_currency, pc.exrt_buy,pc.exrt_sell);
   listView.setAdapter(bindingData);
   }
  } catch (Exception e) {
   e.getMessage();
  }
 }
}


public class BindingData extends BaseAdapter {

ArrayList<String> date;
ArrayList<String> from_currency;
 ArrayList<String> to_currency;
 ArrayList<String> exrt_buy;
 ArrayList<String> exrt_sell;
 LayoutInflater inflater;

 public BindingData() {

 }

 public BindingData(Activity act,ArrayList<String> date, ArrayList<String> from_currency,
   ArrayList<String> to_currency, ArrayList<String> exrt_buy,ArrayList<String> exrt_sell) {

  this.date=date;
  this.from_currency = from_currency;
  this.to_currency = to_currency;
  this.exrt_buy = exrt_buy;
  this.exrt_sell = exrt_sell;

  inflater = (LayoutInflater) act
    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
 }

 @Override
 public int getCount() {
  return date.size();
 }

 @Override
 public Object getItem(int position) {
  return null;
 }

 @Override
 public long getItemId(int position) {
  return 0;
 }

 @Override
 public View getView(int position, View convertView, ViewGroup parent) {
  Holder holder;
  if (convertView == null) {
   holder = new Holder();

   convertView = inflater.inflate(R.layout.listview_row, null);
   holder.txt_date = (TextView) convertView.findViewById(R.id.date);
   holder.txt_FromCurrency = (TextView) convertView.findViewById(R.id.from_currency);
   holder. txt_toCurrency = (TextView) convertView.findViewById(R.id.to_currency);
   holder.txt_exrtBuy = (TextView) convertView.findViewById(R.id.exrt_buy);
   holder.txt_exrtSell = (TextView) convertView.findViewById(R.id.exrt_sell);
   convertView.setTag(holder);
  } else {
   holder = (Holder) convertView.getTag();
  }

  holder.txt_date.setText(Html.fromHtml("" + date.get(position)));
  holder.txt_FromCurrency.setText(Html.fromHtml("" + from_currency.get(position)));
  holder.txt_toCurrency.setText(Html.fromHtml("<b>To Currency : </b>"+ to_currency.get(position)));
  holder.txt_exrtBuy.setText(Html.fromHtml("<b>Buying : </b>" + exrt_buy.get(position)));
  holder.txt_exrtSell.setText(Html.fromHtml("<b>Selling : </b>" + exrt_sell.get(position)));
  return convertView;
 }

 private class Holder {
  TextView txt_date,txt_FromCurrency, txt_toCurrency, txt_exrtBuy,txt_exrtSell;
 }
}



public class ParsingClass extends DefaultHandler {

ArrayList<String> date = new ArrayList<String>();
ArrayList<String> from_currency = new ArrayList<String>();
 ArrayList<String> to_currency = new ArrayList<String>();
 ArrayList<String> exrt_buy = new ArrayList<String>();
 ArrayList<String> exrt_sell = new ArrayList<String>();


 @Override
 public void startElement(String uri, String localName, String qName,
   Attributes attributes) throws SAXException {
  super.startElement(uri, localName, qName, attributes);

  if (localName.equalsIgnoreCase("Date")) {
       tempStore = "";
  }else if (localName.equalsIgnoreCase("From_Currency")) {
   tempStore = "";
  } else if (localName.equalsIgnoreCase("To_Currency")) {
   tempStore = "";
  } else if (localName.equalsIgnoreCase("exrt_buy")) {
   tempStore = "";
  } else if (localName.equalsIgnoreCase("exrt_sell")) {
       tempStore = "";
  }else{
   tempStore = "";
  }
 }

 @Override
 public void endElement(String uri, String localName, String qName)
   throws SAXException {
  super.endElement(uri, localName, qName);

  if (localName.equalsIgnoreCase("Date")) {
      date.add(tempStore);
  }
  else if (localName.equalsIgnoreCase("From_Currency")) {
      from_currency.add(tempStore);
  } else if (localName.equalsIgnoreCase("To_Currency")) {
      to_currency.add(tempStore);
  } else if (localName.equalsIgnoreCase("exrt_buy")) {
      exrt_buy.add(tempStore);
  } else if (localName.equalsIgnoreCase("exrt_sell")) {
      exrt_sell.add(tempStore);
  }
  tempStore = "";
 }

 private String tempStore = "";

 @Override
 public void characters(char[] ch, int start, int length)
   throws SAXException {
  super.characters(ch, start, length);
  tempStore += new String(ch, start, length);
 }
}