android - 如何从android中的网站读取xml文件

Question

我想从网站“sjc.com.vn”读取文件 xml，但它不起作用。这是我的源代码，我没有错在哪里

enter code here

公共类 OrderXMLHandler 扩展 DefaultHandler {

boolean currentElement = false;
String currentValue = "";

String ratelist;
String updated;
ProductInfo productInfo;
ArrayList<ProductInfo> cartList;

public String getRatelist() {
    return ratelist;
}
public void setRatelist(String ratelist) {
    this.ratelist = ratelist;
}
public String getUpdated() {
    return updated;
}
public void setUpdated(String updated) {
    this.updated = updated;
}

public ArrayList<ProductInfo> getCartList() {
    return cartList;
}

public void setCartList(ArrayList<ProductInfo> cartList) {
    this.cartList = cartList;
}
public void startElement(String uri, String localName, String qName,
        Attributes attributes) throws SAXException {

    currentElement = true;

    if(qName.equals("root")){
         cartList = new ArrayList<ProductInfo>();

    } else if(qName.equals("city"))
        productInfo = new ProductInfo();


}

public void endElement(String uri, String localName, String qName)
        throws SAXException {

    currentElement = false;
    if(localName.equalsIgnoreCase("city"))
        productInfo.setName(currentValue.trim());
    else if (localName.equalsIgnoreCase("buy"))
        productInfo.setBuy(currentValue.trim());
    else if (localName.equalsIgnoreCase("sell"))
        productInfo.setSell(currentValue.trim());
    else if (localName.equalsIgnoreCase("type"))
        productInfo.setType(currentValue.trim());
    else if (localName.equalsIgnoreCase("city"))
        cartList.add(productInfo);
    currentValue = "";
}

public void characters(char[] ch, int start, int length)
        throws SAXException {

    if (currentElement) {
        currentValue = currentValue + new String(ch, start, length);
    }
}

}

公共类 MainActivity 扩展 Activity {

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //Thực hiện hàm phân tích XML
    parseXML();
}
//Hàm phân tích XML
private void parseXML(){

    try {

        URL url=new URL("http://www.sjc.com.vn/xml/tygiavang.xml");

        SAXParserFactory spf = SAXParserFactory.newInstance();
        SAXParser sp = spf.newSAXParser();

        XMLReader xr = sp.getXMLReader();

        OrderXMLHandler myXMLHandler = new OrderXMLHandler();

        xr.setContentHandler(myXMLHandler);

        xr.parse(new InputSource(url.openStream()));


         TextView tv = new TextView(this);
         LinearLayout ll = (LinearLayout) findViewById(R.id.linearLayout1);

        //In chi tiết sản phẩm ra giao diện ứng dụng
        ArrayList<ProductInfo> cartList = myXMLHandler.getCartList();
        for (ProductInfo productInfo : cartList) {
            tv = new TextView(this);
            tv.setText("Ten Thanh Pho: " + productInfo.getName());
            ll.addView(tv);
            tv = new TextView(this);
            tv.setText("Buy : " + productInfo.getBuy());
            ll.addView(tv);
            tv = new TextView(this);
            tv.setText("sell : " + productInfo.getSell());
            ll.addView(tv);
            tv = new TextView(this);
            tv.setText("type : " + productInfo.getType());
            ll.addView(tv);
            tv = new TextView(this);
            tv.setText("---");
            ll.addView(tv);
        }

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

}

公共类产品信息 {

String type="";
String sell="";
String buy="";
String name ="";
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getType() {
    return type;
}
public void setType(String type) {
    this.type = type;
}
public String getSell() {
    return sell;
}
public void setSell(String sell) {
    this.sell = sell;
}
public String getBuy() {
    return buy;
}
public void setBuy(String buy) {
    this.buy = buy;
}

}