Android应用程序中的Facebook RSS Feed崩溃

Question

So I tried to set up an RSS feed for my Android application with the attached code, yet when I run it on the emulator, it crashes and I receive the attached errors in my LogCat. Any ideas for what could be wrong? Thanks in advance!!!

package com.fixed_gear_app;

import java.io.IOException;
import java.net.URL;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
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;

public class RSSFeed extends Activity {
     /** Called when the activity is first created. */
    String rssResult = "";
    boolean item = false;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_rssfeed);
        TextView rss = (TextView) findViewById(R.id.rss);
        try {
            URL rssUrl = new URL("https://www.facebook.com/feeds/page.php?format=rss20&id=619608694724497");
            SAXParserFactory factory = SAXParserFactory.newInstance();
            SAXParser saxParser = factory.newSAXParser();
            XMLReader xmlReader = saxParser.getXMLReader();
            RSSHandler rssHandler = new RSSHandler();
            xmlReader.setContentHandler(rssHandler);
            InputSource inputSource = new InputSource(rssUrl.openStream());
            xmlReader.parse(inputSource);

        } catch (IOException e) {rss.setText(e.getMessage());
        } catch (SAXException e) {rss.setText(e.getMessage());
        } catch (ParserConfigurationException e) {rss.setText(e.getMessage());
        }

        rss.setText(rssResult);
    }
    /**public String removeSpaces(String s) {
          StringTokenizer st = new StringTokenizer(s," ",false);
          String t="";
          while (st.hasMoreElements()) t += st.nextElement();
          return t;
        }*/
    private class RSSHandler extends DefaultHandler {

        public void startElement(String uri, String localName, String qName,
                Attributes attrs) throws SAXException {
            if (localName.equals("item"))
                item = true;

            if (!localName.equals("item") && item == true)
                rssResult = rssResult + localName + ": ";

        }

        public void endElement(String namespaceURI, String localName,
                String qName) throws SAXException {

        }

        public void characters(char[] ch, int start, int length)
                throws SAXException {
            String cdata = new String(ch, start, length);
            if (item == true)
                rssResult = rssResult +(cdata.trim()).replaceAll("\\s+", " ")+"\t";

        }

    }
}

Answer 1

You are attempting to do network communication on the main Activity thread. Android, by default, disallows this, (as you do not know how long it can take) so you will have to move your networking code to a class extending AsyncTask. Have a read of this , which shows you how to put it on an AsyncTask.