Java 自定义列表视图捕获异常

参考教程

我正在努力从url获取缩略图。customizedListView类：

public class CustomizedListView extends Activity

{
// All static variables
static final String URL = "http://173.193.24.66/~kanz/video/XML/9.xml";
// XML node keyse.
static final String KEY_SONG = "item"; // parent node
static final String KEY_TITLE = "title";
static final String KEY_ARTIST = "description";
static final String KEY_DURATION = "duration";
static final String KEY_THUMB_URL = "image";
ListView list;
LazyAdapter adapter;

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

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

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

    NodeList nl = doc.getElementsByTagName(KEY_SONG);
    // looping through all song nodes <song>
    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_TITLE, parser.getValue(e, KEY_TITLE));
        map.put(KEY_ARTIST, parser.getValue(e, KEY_ARTIST));
        map.put(KEY_DURATION, parser.getValue(e, KEY_DURATION));
        map.put(KEY_THUMB_URL, parser.getValue(e, KEY_THUMB_URL));

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

    list=(ListView)findViewById(R.id.list);

    // Getting adapter by passing xml data ArrayList
    adapter=new LazyAdapter(this, songsList);
    list.setAdapter(adapter);

    // Click event for single list row
    list.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {
            Context context = getApplicationContext();
             Intent in = new Intent(context, SingleMenuItemActivity.class);
             in.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);                
             context.startActivity(in);

        }
    });
}

请帮帮我，我做错了什么。logcat给出了这个异常，在emulator上，我收到一个警告，说“不幸的是，myApp已经停止”，我们将非常感谢您的帮助。谢谢PS：我已经提到了清单中的所有活动，并且拥有所有权限

编辑：这是我的XML：

<playlist><title>![CDATA[New Playlist]]</title>
<items>
<item>
<title>HAMD(LA ILAHA ILLALLAH)</title>
<description>Recited By :Alhaaj Muhammad Owais Raza Qadri -- Written By: Mufti-e-Azam Hind Molana Mustafa Raza Khan Noori</description>
<image>http://173.193.24.66/~kanz/video/Images/9.jpg</image>

<startFromThis>true</startFromThis>
<duration>510</duration>
<source>http://173.193.24.66/~kanz/video/flv/9.flv</source>
<sourceAlt>http://173.193.24.66/~kanz/video/mp4/9.mp4</sourceAlt>    

<sourceType>direct</sourceType>
</item>
</items>
</playlist>

！[CDATA[新播放列表]]
哈姆德（拉伊拉哈·伊拉拉）
朗诵人：Alhaaj Muhammad Owais Raza Qadri——作者：Mufti-e-Azam Hind Molana Mustafa Raza Khan Noori
http://173.193.24.66/~kanz/video/Images/9.jpg
真的
510
http://173.193.24.66/~kanz/video/flv/9.flv
http://173.193.24.66/~kanz/video/mp4/9.mp4
直接的

两个原因

• 您是否已将清单中的活动声明为：

• 如果不是上述原因，那么您可以检查活动类的名称，其中一定有一些输入错误

您是否有

内部布局文件

---

它可能没有找到id为

list

的元素。我使用编辑过的方法getDoElement（在XMLParser类中）解决了这个问题，如下所示：

 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("http://x.x.x.x/~kanz/video/XML/9.xml"); 

        } 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;
}

我不知道为什么，但在评论完

InputSource is = new InputSource();
is.setCharacterStream(new StringReader(xml));

---

将URL直接传递给db.parse解决了我的问题。希望它也能帮助别人

如果您发布完整的日志消息，这将对人们有所帮助。@android.fryo查看我的更新问题您可以发布完整的定制ListView类吗？日志文件中的行号没有告诉我们任何信息。@coderek它是完整的类。

import

语句不包括在内，我不知道com.example.razatubevidurl.CustomizedListView.onCreate上的

（CustomizedListView.java:49）

指向哪一行。@AbdusSamiKhan发布完整日志。查看更新的问题，如果您认为有问题，请告诉我。

 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("http://x.x.x.x/~kanz/video/XML/9.xml"); 

        } 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;
}

InputSource is = new InputSource();
is.setCharacterStream(new StringReader(xml));