1

我已经按照本教程进行操作,但是当我尝试运行应用程序时,我得到“不幸的是 RSSPro 已停止”。

这是我的 RSSProActivity 代码:

package com.android.rss;

import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;

import android.app.ListActivity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class RSSProActivity extends ListActivity {

    ArrayList<String> headlines;
    ArrayList<String> links;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);


     // Initializing instance variables
        headlines = new ArrayList<String>();
        links = new ArrayList<String>();

        try {
            URL url = new URL("http://www.bom.gov.au/fwo/IDZ00059.warnings_vic.xml");

            XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
            factory.setNamespaceAware(false);
            XmlPullParser xpp = factory.newPullParser();

                // We will get the XML from an input stream
            xpp.setInput(getInputStream(url), "UTF_8");

                /* We will parse the XML content looking for the "<title>" tag which appears inside the "<item>" tag.
                 * However, we should take in consideration that the rss feed name also is enclosed in a "<title>" tag.
                 * As we know, every feed begins with these lines: "<channel><title>Feed_Name</title>...."
                 * so we should skip the "<title>" tag which is a child of "<channel>" tag,
                 * and take in consideration only "<title>" tag which is a child of "<item>"
                 *
                 * In order to achieve this, we will make use of a boolean variable.
                 */
            boolean insideItem = false;

                // Returns the type of current event: START_TAG, END_TAG, etc..
            int eventType = xpp.getEventType();
            while (eventType != XmlPullParser.END_DOCUMENT) {
                if (eventType == XmlPullParser.START_TAG) {

                    if (xpp.getName().equalsIgnoreCase("item")) {
                        insideItem = true;
                    } else if (xpp.getName().equalsIgnoreCase("title")) {
                        if (insideItem)
                            headlines.add(xpp.nextText()); //extract the headline
                    } else if (xpp.getName().equalsIgnoreCase("link")) {
                        if (insideItem)
                            links.add(xpp.nextText()); //extract the link of article
                    }
                }else if(eventType==XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item")){
                    insideItem=false;
                }

                eventType = xpp.next(); //move to next element
            }

        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (XmlPullParserException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        // Binding data
        ArrayAdapter adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1, headlines);
        setListAdapter(adapter);

    }

    public InputStream getInputStream(URL url) {
           try {
               return url.openConnection().getInputStream();
           } catch (IOException e) {
               return null;
             }
        }

    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
        String positions = (String) links.get(position);
       Uri uri = Uri.parse(positions);
       Intent intent = new Intent(Intent.ACTION_VIEW, uri);
       startActivity(intent);
    }

}

我的 main.xml 看起来像这样:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
</ListView>

</LinearLayout>

LogCat 消息:

05-21 19:44:40.528: D/dalvikvm(528): Not late-enabling CheckJNI (already on)
05-21 19:44:41.716: I/dalvikvm(528): threadid=3: reacting to signal 3
05-21 19:44:41.726: I/dalvikvm(528): Wrote stack traces to '/data/anr/traces.txt'
05-21 19:44:41.946: D/dalvikvm(528): GC_FOR_ALLOC freed 87K, 3% free 9136K/9347K, paused 113ms
05-21 19:44:41.956: I/dalvikvm-heap(528): Grow heap (frag case) to 9.904MB for 960016-byte allocation
05-21 19:44:42.056: D/dalvikvm(528): GC_CONCURRENT freed 1K, 3% free 10072K/10311K, paused 6ms+14ms
05-21 19:44:42.176: D/dalvikvm(528): GC_FOR_ALLOC freed 0K, 3% free 10072K/10311K, paused 38ms
05-21 19:44:42.196: I/dalvikvm-heap(528): Grow heap (frag case) to 11.963MB for 2160016-byte allocation
05-21 19:44:42.217: I/dalvikvm(528): threadid=3: reacting to signal 3
05-21 19:44:42.306: I/dalvikvm(528): Wrote stack traces to '/data/anr/traces.txt'
05-21 19:44:42.316: D/dalvikvm(528): GC_CONCURRENT freed 0K, 2% free 12181K/12423K, paused 3ms+4ms
05-21 19:44:42.526: D/gralloc_goldfish(528): Emulator without GPU emulation detected.
05-21 19:44:48.076: I/dalvikvm(528): threadid=3: reacting to signal 3
05-21 19:44:48.206: D/AndroidRuntime(528): Shutting down VM
05-21 19:44:48.206: W/dalvikvm(528): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
05-21 19:44:48.216: I/dalvikvm(528): Wrote stack traces to '/data/anr/traces.txt'
05-21 19:44:48.396: E/AndroidRuntime(528): FATAL EXCEPTION: main
05-21 19:44:48.396: E/AndroidRuntime(528): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.android.rss/com.android.rss.RSSProActivity}: android.os.NetworkOnMainThreadException
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.app.ActivityThread.access$600(ActivityThread.java:123)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.os.Looper.loop(Looper.java:137)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.app.ActivityThread.main(ActivityThread.java:4424)
05-21 19:44:48.396: E/AndroidRuntime(528):  at java.lang.reflect.Method.invokeNative(Native Method)
05-21 19:44:48.396: E/AndroidRuntime(528):  at java.lang.reflect.Method.invoke(Method.java:511)
05-21 19:44:48.396: E/AndroidRuntime(528):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
05-21 19:44:48.396: E/AndroidRuntime(528):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
05-21 19:44:48.396: E/AndroidRuntime(528):  at dalvik.system.NativeStart.main(Native Method)
05-21 19:44:48.396: E/AndroidRuntime(528): Caused by: android.os.NetworkOnMainThreadException
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
05-21 19:44:48.396: E/AndroidRuntime(528):  at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
05-21 19:44:48.396: E/AndroidRuntime(528):  at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
05-21 19:44:48.396: E/AndroidRuntime(528):  at java.net.InetAddress.getAllByName(InetAddress.java:220)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpConnection.<init>(HttpConnection.java:71)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:351)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:86)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:308)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpEngine.connect(HttpEngine.java:303)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:282)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:232)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:273)
05-21 19:44:48.396: E/AndroidRuntime(528):  at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:168)
05-21 19:44:48.396: E/AndroidRuntime(528):  at com.android.rss.RSSProActivity.getInputStream(RSSProActivity.java:92)
05-21 19:44:48.396: E/AndroidRuntime(528):  at com.android.rss.RSSProActivity.onCreate(RSSProActivity.java:48)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.app.Activity.performCreate(Activity.java:4465)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
05-21 19:44:48.396: E/AndroidRuntime(528):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
05-21 19:44:48.396: E/AndroidRuntime(528):  ... 11 more
05-21 19:44:48.616: I/dalvikvm(528): threadid=3: reacting to signal 3
05-21 19:44:48.708: I/dalvikvm(528): Wrote stack traces to '/data/anr/traces.txt'
05-21 19:44:49.116: I/dalvikvm(528): threadid=3: reacting to signal 3
05-21 19:44:49.206: I/dalvikvm(528): Wrote stack traces to '/data/anr/traces.txt'
05-21 19:44:49.436: I/dalvikvm(528): threadid=3: reacting to signal 3
05-21 19:44:49.476: I/dalvikvm(528): Wrote stack traces to '/data/anr/traces.txt'
05-21 19:44:56.997: I/Process(528): Sending signal. PID: 528 SIG: 9

我目前正在使用 SDK 15 版本(Android 4.0.3)。我的代码可以在 Eclipse 中编译,但无法在模拟器上运行。我做错了什么?

4

1 回答 1

1

您正面临NetworkOnMainThreadException因为在主线程中检索 XML。用于AsyncTask在后台执行 XML 的获取和解析。示例可以在:Read RSS in background, using AsyncTask

于 2012-05-21T09:19:58.073 回答