Question

我已经看过很多关于此的帖子，但实际上我没有得到任何工作。我正在构建一个简单的电视指南android应用程序。我只是使用tvprofil.net上的RSS来显示今天的电视节目。问题是，我不知道如何在XML中解析CDATA。我正在使用一些带DOM的标准解析器......至少我是这么认为的。

这是一点XML：

.
.
.
<item>
<title>RTS1 14.08.2012</title>
<pubDate>Tue, 14 Aug 2012 06:00:00</pubDate>
<content:encoded><![CDATA[06:00 Vesti<br>06:05 Jutarnji program<br>08:00 Dnevnik
<br>8:15 Jutarnji Program<br>09:00 Vesti ... ]]></content:encoded>
</item>
.
.
.

现在，这是我的主要应用程序：

public class Main extends ListActivity {

// All static variables
static final String URL = "http://tvprofil.net/rss/feed/channel-group-2.xml";
// XML node keys
static final String KEY_ITEM = "item"; // parent node
static final String KEY_NAME = "title";
static final String KEY_DATE = "pubDate";
static final String KEY_DESC = "content:encoded";

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


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



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



    NodeList nl = doc.getElementsByTagName(KEY_ITEM);
    //loop
    for (int i=0; i< nl.getLength(); i++){
        HashMap<String, String> map = new HashMap<String, String>();
        Element e = (Element) nl.item(i);
        //add to map
        map.put(KEY_NAME, parser.getValue(e, KEY_NAME));
        map.put(KEY_DATE, parser.getValue(e, KEY_DATE));
        map.put(KEY_DESC, parser.getValue(e, KEY_DESC));

        // hash => list
        menuItems.add(map);
    }

    ListAdapter adapter = new SimpleAdapter(this, menuItems, R.layout.list_item,
            new String[]{KEY_NAME, KEY_DESC, KEY_DATE}, new int[]{
            R.id.name, R.id.description, R.id.date
    });
    setListAdapter(adapter);

    //singleView
    ListView lv = getListView();

    lv.setOnItemClickListener(new OnItemClickListener(){
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id){
            String name = ((TextView)view.findViewById(R.id.name)).getText().toString();
            String date = ((TextView)view.findViewById(R.id.date)).getText().toString();
            String description = ((TextView)view.findViewById(R.id.description)).getText().toString();

            //intent
            Intent in = new Intent(getApplicationContext(), SingleMenuItemActivity.class);
            in.putExtra(KEY_NAME, name);
            in.putExtra(KEY_DATE, date);
            in.putExtra(KEY_DESC, description);
            startActivity(in);
        }
    });

}

}

和解析器类：

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));
    }
}

单个菜单项还有一个类..但我认为在这种情况下它是无关紧要的。现在，我只想在解析它并处理CDATA之后看不到HTML标签...... 有人知道这个吗？

Answer 1

添加此

 dbf.setCoalescing(true);

其中dbf是

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

Answer 2

首先添加此方法

public String getCharacterDataFromElement(Element e, String str) {
NodeList n = e.getElementsByTagName(str);   
Element e1=(Element) n.item(0);

Node child = e1.getFirstChild();
if (child instanceof CharacterData) {
  CharacterData cd = (CharacterData) child;
  return cd.getData();
}
return "";
}

调用上述方法 -

map.put(KEY_DESC, parser.getCharacterDataFromElement(e, KEY_DESC));

这应该以String格式获取CDATA。 HOpe这有帮助

Answer 3

getTextContent。此属性返回此节点及其的文本内容后代

getNodeValue（）此节点的值，取决于其类型;

通常你会使用getTextContent。

Answer 4

当我需要从一组“description”xml元素中提取CDATA中的图像URL时，zg_spring的答案对我来说非常有用：

//Get the content of all "item" elements    
DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = db.parse(new InputSource(new StringReader(xml)));
NodeList nlDetails = doc.getElementsByTagName("item");    

//Loop through elements and extract content of "description" elements    
for(int k = 0; k < numDetails; k++) {
    Element nDetails = (Element)nlDetails.item(k);
    NodeList nlCoverURL = nDetails.getElementsByTagName("description");         
    Node nCoverURL = nlCoverURL.item(0);
    String sCoverURL = nCoverURL.getTextContent();

    //Isolate the relevant part of the String and load it into an ArrayList
    String[] descriptionContent = sCoverURL.split("\"");
    String s = descriptionContent[11]
    alImages.add(s);
}

在针对ANDROID的此特定情况下，使用XMLParser解析CDATA

4 个答案: