android load rss item into listview

Question

Hi i would load rss item into a listview in my MainActivity. For this, i'm using this RSS-Reader-Library

https://github.com/matshofman/Android-RSS-Reader-Library

In his description developer explain how use these library, simply using

URL url = new URL("http://example.com/feed.rss");
RssFeed feed = RssReader.read(url);

ArrayList<RssItem> rssItems = feed.getRssItems();
for(RssItem rssItem : rssItems) {
    Log.i("RSS Reader", rssItem.getTitle());
}

I have tried but my application crash at start. Here my MainActivity:

public class MainActivity extends ActionBarActivity{

    private ListView listview;
    URL url = null;
    RssFeed feed = null;

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

        listview = (ListView) findViewById(R.id.listView);

        try {
            url = new URL("http://www.unikore.it/index.php/ingegneria-informatica-home?format=feed");
        } catch (MalformedURLException e) {
            e.printStackTrace();
        }

        try {
            feed = RssReader.read(url);
        } catch (SAXException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        ArrayList<RssItem> rssItems = (ArrayList<RssItem>)feed.getRssItems();
        ArrayAdapter<RssItem> list = new ArrayAdapter<RssItem>(getBaseContext(), android.R.layout.simple_list_item_1, rssItems);
        listview.setAdapter(list);
        for(RssItem rssItem : rssItems) {

            Log.i("RSS Reader", rssItem.getTitle());
        }
    }
}

This is the logacat:

04-24 13:09:03.120  32415-32415/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.asuspc.rssfeed/com.example.asuspc.rssfeed.MainActivity}: android.os.NetworkOnMainThreadException
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
            at android.app.ActivityThread.access$600(ActivityThread.java:141)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:5103)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:525)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: android.os.NetworkOnMainThreadException
            at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1133)
            at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
            at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
            at java.net.InetAddress.getAllByName(InetAddress.java:214)
            at libcore.net.http.HttpConnection.<init>(HttpConnection.java:70)
            at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
            at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:340)
            at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87)
            at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
            at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:316)
            at libcore.net.http.HttpEngine.connect(HttpEngine.java:311)
            at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:290)
            at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:240)
            at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:282)
            at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:177)
            at java.net.URL.openStream(URL.java:462)
            at com.example.asuspc.rssfeed.RssReader.read(RssReader.java:36)
            at com.example.asuspc.rssfeed.MainActivity.onCreate(MainActivity.java:46)
            at android.app.Activity.performCreate(Activity.java:5133)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
            at android.app.ActivityThread.access$600(ActivityThread.java:141)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:5103)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:525)

The exception is: android.os.NetworkOnMainThreadException Can you explain me how load rss items and show eachone into my listview please?

Thanks

You are doing Network operation on main thread see line no 46 of MainActivity. put your operation under AsyncTask and every thing will be fine. — MrDumb, Apr 24 '15 at 11:17

Euporie · Accepted Answer · 2015-04-24T12:27:56.043

Try to use AsyncTask like this:

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

    listview = (ListView) findViewById(R.id.listView);

    try {
        url = new URL(
                "http://www.unikore.it/index.php/ingegneria-informatica-home?format=feed");
    } catch (MalformedURLException e) {
        e.printStackTrace();
    }
    new ReadRssTask().execute(url);
}

private class ReadRssTask extends AsyncTask<URL, Void, RssFeed> {

    @Override
    protected RssFeed doInBackground(URL... params) {
        RssFeed result = null;
        URL url = params[0];
        if (!TextUtils.isEmpty(url)) {
            try {
                result = RssReader.read(url);
            } catch (SAXException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return result;
    }

    protected void onPostExecute(RssFeed result) {
        if (result != null) {
            ArrayList<RssItem> rssItems = (ArrayList<RssItem>) result
                    .getRssItems();
            List<String> titles = new ArrayList<String>();
            for (RssItem rssItem : rssItems) {
                titles.add(rssItem.getTitle());
            }
            ArrayAdapter<String> list = new ArrayAdapter<String>(
                    getBaseContext(), android.R.layout.simple_list_item_1,
                    titles);
            listview.setAdapter(list);
        }
    }

}

Hope it helps.

thanks now it works...but items listed in listview aren't correct,why? am i parsing wronged information? — xXJohnRamboXx, Apr 24 '15 at 11:58
it should shows me tag content of the webpage but it shows me wrong string..i think the problem is that my listview has RssItem adapter but i should insert rssItem.getTitle(); — xXJohnRamboXx, Apr 24 '15 at 12:04
@xXJohnRamboXx if you mean to show title in the ListView, please see the edited post. — Euporie, Apr 24 '15 at 12:27

android load rss item into listview

1 Answers1