我在我的Android应用程序中创建一个rss feed。 但是我不断发生这个错误。
这是我的logcat错误......
03-12 14:04:04.025: E/RSS ERROR(4808): Error loading RSS Feed Stream >> null //android.os.NetworkOnMainThreadException
03-12 14:04:04.285: I/dalvikvm(4808): threadid=3: reacting to signal 3
03-12 14:04:04.305: I/dalvikvm(4808): Wrote stack traces to '/data/anr/traces.txt'
03-12 14:04:04.335: D/ViewRootImpl(4808): pckname = com.tmm.android.rssreader
03-12 14:04:04.485: D/libEGL(4808): loaded /system/lib/egl/libEGL_mali.so
03-12 14:04:04.525: D/libEGL(4808): loaded /system/lib/egl/libGLESv1_CM_mali.so
03-12 14:04:04.535: D/libEGL(4808): loaded /system/lib/egl/libGLESv2_mali.so
03-12 14:04:04.575: D/OpenGLRenderer(4808): Enabling debug mode 0
有人可以帮忙吗？我是RSS新手
我不确定代码中的哪个部分会出现错误，有什么建议吗？
package com.tmm.android.rssreader.util;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import android.util.Log;
public class RSSHandler extends DefaultHandler {
// Feed and Article objects to use for temporary storage
private Article currentArticle = new Article();
private List<Article> articleList = new ArrayList<Article>();
// Number of articles added so far
private int articlesAdded = 0;
// Number of articles to download
private static final int ARTICLES_LIMIT = 15;
//Current characters being accumulated
StringBuffer chars = new StringBuffer();
/*
* This method is called everytime a start element is found (an opening XML marker)
* here we always reset the characters StringBuffer as we are only currently interested
* in the the text values stored at leaf nodes
*
* (non-Javadoc)
* @see org.xml.sax.helpers.DefaultHandler#startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)
*/
public void startElement(String uri, String localName, String qName, Attributes atts) {
chars = new StringBuffer();
}
/*
* This method is called everytime an end element is found (a closing XML marker)
* here we check what element is being closed, if it is a relevant leaf node that we are
* checking, such as Title, then we get the characters we have accumulated in the StringBuffer
* and set the current Article's title to the value
*
* If this is closing the "Item", it means it is the end of the article, so we add that to the list
* and then reset our Article object for the next one on the stream
*
*
* (non-Javadoc)
* @see org.xml.sax.helpers.DefaultHandler#endElement(java.lang.String, java.lang.String, java.lang.String)
*/
public void endElement(String uri, String localName, String qName) throws SAXException {
if (localName.equalsIgnoreCase("title"))
{
Log.d("LOGGING RSS XML", "Setting article title: " + chars.toString());
currentArticle.setTitle(chars.toString());
}
else if (localName.equalsIgnoreCase("description"))
{
Log.d("LOGGING RSS XML", "Setting article description: " + chars.toString());
currentArticle.setDescription(chars.toString());
}
else if (localName.equalsIgnoreCase("pubDate"))
{
Log.d("LOGGING RSS XML", "Setting article published date: " + chars.toString());
currentArticle.setPubDate(chars.toString());
}
else if (localName.equalsIgnoreCase("encoded"))
{
Log.d("LOGGING RSS XML", "Setting article content: " + chars.toString());
currentArticle.setEncodedContent(chars.toString());
}
else if (localName.equalsIgnoreCase("item"))
{
}
else if (localName.equalsIgnoreCase("link"))
{
try {
Log.d("LOGGING RSS XML", "Setting article link url: " + chars.toString());
currentArticle.setUrl(new URL(chars.toString()));
} catch (MalformedURLException e) {
Log.e("RSA Error", e.getMessage());
}
}
// Check if looking for article, and if article is complete
if (localName.equalsIgnoreCase("item")) {
articleList.add(currentArticle);
currentArticle = new Article();
// Lets check if we've hit our limit on number of articles
articlesAdded++;
if (articlesAdded >= ARTICLES_LIMIT)
{
throw new SAXException();
}
}
}
/*
* This method is called when characters are found in between XML markers, however, there is no
* guarante that this will be called at the end of the node, or that it will be called only once
* , so we just accumulate these and then deal with them in endElement() to be sure we have all the
* text
*
* (non-Javadoc)
* @see org.xml.sax.helpers.DefaultHandler#characters(char[], int, int)
*/
public void characters(char ch[], int start, int length) {
chars.append(new String(ch, start, length));
}
/**
* This is the entry point to the parser and creates the feed to be parsed
*
* @param feedUrl
* @return
*/
public List<Article> getLatestArticles(String feedUrl) {
URL url = null;
try {
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();
XMLReader xr = sp.getXMLReader();
url = new URL(feedUrl);
xr.setContentHandler(this);
xr.parse(new InputSource(url.openStream()));
} catch (IOException e) {
Log.e("RSS Handler IO", e.getMessage() + " >> " + e.toString());
} catch (SAXException e) {
Log.e("RSS Handler SAX", e.toString());
} catch (ParserConfigurationException e) {
Log.e("RSS Handler Parser Config", e.toString());
}
return articleList;
}
}
用于已阅读RSS阅读器的新LOGCAT日志
03-12 16:01:13.882: W/System.err(5792): java.net.UnknownHostException: Unable to resolve host "www.cnn.com": No address associated with hostname
03-12 16:01:13.882: W/System.err(5792): at java.net.InetAddress.lookupHostByName(InetAddress.java:426)
03-12 16:01:13.912: W/System.err(5792): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
03-12 16:01:13.912: W/System.err(5792): at java.net.InetAddress.getAllByName(InetAddress.java:220)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:71)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:351)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:86)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:308)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpEngine.connect(HttpEngine.java:303)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:282)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:232)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:273)
03-12 16:01:13.912: W/System.err(5792): at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:168)
03-12 16:01:13.922: W/System.err(5792): at java.net.URL.openStream(URL.java:462)
03-12 16:01:13.922: W/System.err(5792): at com.exercise.AndroidRssReader.AndroidRssReader$MyTask.doInBackground(AndroidRssReader.java:43)
03-12 16:01:13.922: W/System.err(5792): at com.exercise.AndroidRssReader.AndroidRssReader$MyTask.doInBackground(AndroidRssReader.java:1)
03-12 16:01:13.922: W/System.err(5792): at android.os.AsyncTask$2.call(AsyncTask.java:264)
03-12 16:01:13.922: W/System.err(5792): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
03-12 16:01:13.922: W/System.err(5792): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
03-12 16:01:13.932: W/System.err(5792): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
03-12 16:01:13.932: W/System.err(5792): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
03-12 16:01:13.932: W/System.err(5792): at java.lang.Thread.run(Thread.java:856)
03-12 16:01:13.932: W/System.err(5792): Caused by: libcore.io.GaiException: getaddrinfo failed: EAI_NODATA (No address associated with hostname)
03-12 16:01:13.952: W/System.err(5792): at libcore.io.Posix.getaddrinfo(Native Method)
03-12 16:01:13.952: W/System.err(5792): at libcore.io.ForwardingOs.getaddrinfo(ForwardingOs.java:55)
03-12 16:01:13.952: W/System.err(5792): at java.net.InetAddress.lookupHostByName(InetAddress.java:411)
03-12 16:01:13.962: W/System.err(5792): ... 22 more
答案 0 :(得分：0)
Error loading RSS Feed Stream >> null //android.os.NetworkOnMainThreadException
这意味着您在UI线程中调用xml解析。 xml解析本身通过url.openStream()中的getLatestArticles()获取数据。使用AsyncTask解析xml并在完成后发布结果。