4

我试图建立一个应用程序来阅读这个提要：http ://loc.grupolusofona.pt/index.php/?format=feed

它工作得很好，除了当它到达元素时，它只是跳过它，让它空白。

这是我得到的：

public class AndroidXMLParsingActivity extends ListActivity {

// All static variables
static final String URL = "http://loc.grupolusofona.pt/index.php/?format=feed";
// XML node keys
static final String KEY_ITEM = "item"; // parent node
static final String KEY_ID = "id";
static final String KEY_TITLE = "title";
static final String KEY_DESC = "description";
static final String KEY_LINK = "link";
static final String KEY_PUBDATE = "pubDate";

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

    ArrayList<HashMap<String, String>> menuItems = new ArrayList<HashMap<String, String>>();

    XMLParser parser = new XMLParser();
    String xml = parser.getXmlFromUrl(URL); // getting XML
    Document doc = parser.getDomElement(xml); // getting DOM element

    NodeList nl = doc.getElementsByTagName(KEY_ITEM);
    // looping through all item nodes <item>
    for (int i = 0; i < nl.getLength(); i++) {
        // creating new HashMap
        HashMap<String, String> map = new HashMap<String, String>();
        Element e = (Element) nl.item(i);
        // adding each child node to HashMap key => value
        map.put(KEY_ID, parser.getValue(e, KEY_ID));
        map.put(KEY_TITLE, parser.getValue(e, KEY_TITLE));
        map.put(KEY_DESC, parser.getValue(e, KEY_DESC));
        map.put(KEY_LINK, parser.getValue(e, KEY_LINK));
        map.put(KEY_PUBDATE, parser.getValue(e, KEY_PUBDATE));

        // adding HashList to ArrayList
        menuItems.add(map);
    }

    // Adding menuItems to ListView
    ListAdapter adapter = new SimpleAdapter(this, menuItems,
            R.layout.list_item,
            new String[] { KEY_TITLE, KEY_DESC, KEY_PUBDATE, KEY_LINK }, new int[] {
                    R.id.title, R.id.desc, R.id.pub, R.id.link});

    setListAdapter(adapter);

    // selecting single ListView item
    ListView lv = getListView();

    lv.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {
            // getting values from selected ListItem

            String title = ((TextView) view.findViewById(R.id.title)).getText().toString();
            String description = ((TextView) view.findViewById(R.id.desc)).getText().toString();
            String link = ((TextView) view.findViewById(R.id.link)).getText().toString();

            // Starting new intent

            System.out.println("Title: " + title);
            System.out.println("Link: " + link);
            System.out.println("Description:" + description);
            Intent in = new Intent(Intent.ACTION_VIEW);
            in.setData(Uri.parse(link));

            startActivity(in);

        }
    });
}
}

和 XMLParser：

public class XMLParser {

// constructor
public XMLParser() {

}

/**
 * Getting XML from URL making HTTP request
 * @param url string
 * */
public String getXmlFromUrl(String url) {
    String xml = null;

    try {
        // defaultHttpClient
        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);

        HttpResponse httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        xml = EntityUtils.toString(httpEntity);

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    // return XML
    return xml;
}

/**
 * Getting XML DOM element
 * @param XML string
 * */
public Document getDomElement(String xml){
    Document doc = null;
    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    try {

        DocumentBuilder db = dbf.newDocumentBuilder();

        InputSource is = new InputSource();
            is.setCharacterStream(new StringReader(xml));
            doc = db.parse(is); 

        } catch (ParserConfigurationException e) {
            Log.e("Error: ", e.getMessage());
            return null;
        } catch (SAXException e) {
            Log.e("Error: ", e.getMessage());
            return null;
        } catch (IOException e) {
            Log.e("Error: ", e.getMessage());
            return null;
        }

        return doc;
}

/** Getting node value
  * @param elem element
  */
 public final String getElementValue( Node elem ) {
     Node child;
     if( elem != null){
         if (elem.hasChildNodes()){
             for( child = elem.getFirstChild(); child != null; child = child.getNextSibling() ){
                 if( child.getNodeType() == Node.TEXT_NODE  ){
                     return child.getNodeValue();
                 }
             }
         }
     }
     return "";
 }

 /**
  * Getting node value
  * @param Element node
  * @param key string
  * */
 public String getValue(Element item, String str) {     
        NodeList n = item.getElementsByTagName(str);        
        return this.getElementValue(n.item(0));
    }

}

关于我做错了什么的任何想法？

谢谢

4

3 回答 3

2

我认为，问题在于<description>该站点返回的标签都包含<![CDATA[部分，而不是文本。您的代码XMLParser.getElementValue仅返回TEXT节点的值。改变这个：

if( child.getNodeType() == Node.TEXT_NODE  ){
    return child.getNodeValue();
}

至：

if( child.getNodeType() == Node.TEXT_NODE || child.getNodeType() == Node.CDATA_NODE ){
    return child.getNodeValue();
}
于 2012-11-01T17:25:05.813 回答
0 
public final String getElementValue( Node elem ) {
 Node child;
 if( elem != null){
     if (elem.hasChildNodes()){
         for( child = elem.getFirstChild(); child != null; child = child.getNextSibling() ){
             if( child.getNodeType() == Node.TEXT_NODE  ){
                 return child.getNodeValue();
             }
         }
     }
 }
 return "";
}

您正在使用此代码在解析描述时给出 null 。

我尝试您的代码并获取描述的内容。

我用

child.getTextContent()

它给了我内容。

将您的代码更改为

public final String getElementValue( Node elem ) {
 Node child;
 if( elem != null){
 if (elem.hasChildNodes()){
     for( child = elem.getFirstChild(); child != null; child = child.getNextSibling() ){
         if(child.getNodeName().equalsIgnoreCase("description"))
         {
             return child.getTextContent();
         }
         if( child.getNodeType() == Node.TEXT_NODE  ){
             return child.getNodeValue();
         }
     }
 }
 }
 return "";
}

你也得到了描述的内容...... 试试看..，。

于 2012-11-01T17:53:49.663 回答
0

描述标签包含一个 CDATA 元素。因此它不是一个文本节点，所以你检查

if( child.getNodeType() == Node.TEXT_NODE  )

这些节点将是错误的。孩子很可能是 CDATA_SECTION_NODE。该节点也可能有多个子节点（如果 CDATA 之外的文本包括空格，则为文本节点），在这种情况下您需要处理选择正确的子节点。

于 2012-11-01T17:24:42.270 回答