Android RSS阅读器问题

我一直在试图创建一个简单的应用程序，它将整个频道解析为一个字符串并打印出来，还可以将解析后的数据保存到sqlite数据库中。我一直在关注tutorial1和tutorial2 我也有RSS阅读器的3-4其他实现一起阅读IBM教程，但不能弄清楚什么是错Android RSS阅读器问题

Item.java

public class Item extends Object { 
private String Data= null; 
Item() { 

} 
Item(String data) { 
    this.Data = data; 
} 
public void setData(String data) { 
    this.Data = data; 
} 
public String getData() { 
    return this.Data; 
}

}

RSSHandler的.java

public class RSSHandler extends DefaultHandler { 
public static final String ITEMS_TABLE="items"; 
private final String MY_DEBUG_TAG = "handler"; 
boolean inChannel = false; 
public Item item; 
LearDB leardb = null; 
RSSHandler(Context context) 
{ 
    leardb = new LearDB(context); 
    item =new Item(); 
} 
@Override 
public void startDocument() throws SAXException { 
    this.item = new Item(); 
} 
@Override 
public void endDocument() throws SAXException{ 
} 

@Override 
public void startElement(String Uri, String localName, String qName, 
     Attributes atts) throws SAXException { 
    if (localName.equals("channel")) { 
     this.inChannel = true; 
    } 
    else { 
     return; 
    } 
} 
@Override 
public void endElement(String Uri, String localName, String qName) 
throws SAXException { 
    if (localName.equals("channel")) { 
     this.inChannel = false; 
    } 
    else { 
     return; 
    } 
} 
@Override 
public void characters(char ch[], int start, int length) { 
    String temp = new String(ch, start, length); 
    try { 
     if (this.inChannel) { 
      this.item.setData(temp); 
     } 
    } catch (Exception e) { 
     Log.e(MY_DEBUG_TAG, "Parsing Error", e); 
    } 
} 
public String getData() { 
    return this.item.getData(); 

} 
public Item getItem() { 
    return this.item; 
}  
public void insertItem(String temp) { 
    SQLiteDatabase db = leardb.getWritableDatabase(); 
    ContentValues value=new ContentValues(); 
    value.put("data", temp); 
    db.insert(ITEMS_TABLE, null, value);   
}

}

LearDB.java

public class LearDB extends SQLiteOpenHelper { 
private static final String DATABASE_NAME="lear.db"; 
public static final String ITEMS_TABLE="items"; 

public LearDB(Context context) { 
    super(context, DATABASE_NAME, null, 1);  
} 

@Override 
public void onCreate(SQLiteDatabase db) { 
    String sql = ("CREATE TABLE items (_id INTEGER PRIMARY KEY AUTOINCREMENT, data TEXT);"); 
    db.execSQL(sql);  
} 

@Override 
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { 
    if (oldVersion == 1 && newVersion == 2) { 
     String sql = "drop table items;"; 
     db.execSQL(sql); 
     sql = ("CREATE TABLE items (_id INTEGER PRIMARY KEY AUTOINCREMENT, data TEXT);"); 
     db.execSQL(sql); 
    } 
}

}

主要活动

public class test3 extends Activity { 
private final String MY_DEBUG_TAG = "test2"; 
@Override 
public void onCreate(Bundle icicle) { 
    super.onCreate(icicle); 
    TextView text = new TextView(this); 
    try { 
     URL url = new URL("http://achdre.freehostia.com/example.xml");// URL of XML document to be parsed 
     InputSource source = new InputSource(url.openStream()); 
     SAXParserFactory LearParseFactory = SAXParserFactory.newInstance(); 
     SAXParser LearParser = LearParseFactory.newSAXParser(); //SAX Parser object 
     XMLReader LearReader = LearParser.getXMLReader(); // Object that scans the XML document 
     RSSHandler LearHandler = new RSSHandler(this); //Handler object 
     LearReader.setContentHandler(LearHandler); 
     LearReader.parse(source); //Parses the XML document 
     String temp=LearHandler.getData(); 
     text.setText("12345"); 
     LearHandler.insertItem("android"); //inserting test string to DB 
     } 
    catch (Exception e) { 
     text.setText("Error: " + e.getMessage()); 
     Log.e(MY_DEBUG_TAG, "Parsing Error", e); 
     } 
    this.setContentView(text); 
}}

和清单文件

<uses-sdk android:minSdkVersion="8" /> 
<uses-permission android:name="android.permission.INTERNET"></uses-permission> 
<application android:icon="..." android:label="..."android:debuggable="true"> 
<activity android:name=".test3"android:label="@string/app_name"> 
<intent-filter> 
<action android:name="android.intent.action.MAIN" /> 
<category android:name="android.intent.category.LAUNCHER" /> 
</intent-filter> 
</activity> 
</application> 
android:label="@string/app_name"android:debuggable="true">

编辑：我设法使其运行。错误都是在我尝试解析的xml和我的处理程序类回调事件上。无需更多的援助

来源

2011-03-01 pmantz

这是相当多的处理。你可以通过添加一个虚拟的“Hello World！”来验证你的活动是否正在加载？文本域？此外，您可以尝试在try块中尽早设置断点（在Eclipse中双击左边距），然后在Debug中运行应用程序。 – 2011-03-01 01:31:33

我认为它的加载正常，因为在我的主要活动中创建的'LearHandler'对象的SQLite数据库已正确创建，并且主要的命令实际上是在数据库中插入数据，因为我可以看到当我检索并打开至于断点和调试运行我;我会在早上做，并给你答案感谢您的帮助 – pmantz 2011-03-01 03:32:25

我在调试中运行应用程序。我可以确定发生了什么事情，因为我可以使用'text.setText（“1234”）;' 而不是当我尝试 'String temp = LearHandler.getData（）; 'text.setText（“12345”）;'这样我的处理程序类有什么问题，除此之外，我真的不知道用调试运行找到什么 – pmantz 2011-03-01 12:12:54

可能会帮助

public class RSSHandler extends DefaultHandler 
{ 
    RSSFeed rssFeed; 
    RSSItem rssItem; 
    String lastElementName = ""; 
    final int RSS_TITLE = 1; 
    final int RSS_LINK = 2; 
    final int RSS_DESCRIPTION = 3; 
    final int RSS_CATEGORY = 4; 
    final int RSS_PUBDATE = 5; 

    int currentstate = 0; 

    public RSSHandler() 
    { 
    } 

    public RSSFeed getFeed() 
    { 
     return rssFeed; 
    } 

    //开始解析文档 
    public void startDocument() throws SAXException 
    { 
     rssFeed = new RSSFeed(); 
     rssItem = new RSSItem(); 
    } 

    //文档解析结束 
    public void endDocument() throws SAXException 
    { 
    } 

    public void startElement(String namespaceURI, String localName,String qName, Attributes atts) throws SAXException 
    { 
     if (localName.equals("channel")) 
     { 
      currentstate = 0; 
      return; 
     } 

     if (localName.equals("item")) 
     { 
      rssItem = new RSSItem(); 
      return; 
     } 

     if (localName.equals("title")) 
     { 
      currentstate = RSS_TITLE; 
      return; 
     } 

     if (localName.equals("description")) 
     { 
      currentstate = RSS_DESCRIPTION; 
      return; 
     } 

     if (localName.equals("link")) 
     { 
      currentstate = RSS_LINK; 
      return; 
     } 

     if (localName.equals("category")) 
     { 
      currentstate = RSS_CATEGORY; 
      return; 
     } 

     if (localName.equals("pubDate")) 
     { 
      currentstate = RSS_PUBDATE; 
      return; 
     } 

     currentstate = 0; 
    } 

    public void endElement(String namespaceURI, String localName, String qName) throws SAXException 
    { 
     //如果解析一个item节点结束，就将rssItem添加到rssFeed中。 
     if (localName.equals("item")) 
     { 
      rssFeed.addItem(rssItem); 
      return; 
     } 
    } 

    public void characters(char ch[], int start, int length) 
    { 
     String theString = new String(ch,start,length); 

     switch (currentstate) 
     { 
      case RSS_TITLE: 
       rssItem.setTitle(theString); 
       currentstate = 0; 
       break; 

      case RSS_LINK: 
       rssItem.setLink(theString); 
       currentstate = 0; 
       break; 

      case RSS_DESCRIPTION: 
       rssItem.setDescription(theString); 
       currentstate = 0; 
       break; 

      case RSS_CATEGORY: 
       rssItem.setCategory(theString); 
       currentstate = 0; 
       break; 

      case RSS_PUBDATE: 
       rssItem.setPubDate(theString); 
       currentstate = 0; 
       break; 

      default: 
       return; 
     } 
    } 
}

来源

2011-03-01 01:43:55 Xhinking

Android RSS阅读器问题

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