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解析XML Android – 标记解析

发布时间:2020-12-16 22:50:18 所属栏目:百科 来源:网络整理
导读:我正在尝试构建一个应用程序来阅读此Feed: http://loc.grupolusofona.pt/index.php/?format=feed 它工作得很好,除了它到达元素时,它只是跳过它,留空. 继承人我得到了什么: public class AndroidXMLParsingActivity extends ListActivity {// All static va
我正在尝试构建一个应用程序来阅读此Feed: http://loc.grupolusofona.pt/index.php/?format=feed

它工作得很好,除了它到达元素时,它只是跳过它,留空.

继承人我得到了什么:

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,KEY_TITLE));
        map.put(KEY_DESC,KEY_DESC));
        map.put(KEY_LINK,KEY_LINK));
        map.put(KEY_PUBDATE,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));
    }

}

对于我做错了什么的任何想法?

谢谢

解决方法

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.

我尝试使用您的代码并获取描述内容.

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..,.试试吧..,.

(编辑:李大同)

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