Networkonmainthreadexception error

Question

People are giving this exception because by what I researched, from Android 3.0 you can no longer make network call in an Activity, but I need this to be done:

Check out my Rssfeed reading class :

public class XmlReader {

    private String rssUrl;

    /**
     * Constructor
     */
    public XmlReader(String rssUrl) {
        this.rssUrl = rssUrl;

    }

    /**
     * Pega uma lista de XML.
     * 
     * @return
     */
    public List<Segmento> getItems() throws Exception {
        // SAX parse RSS data
        SAXParserFactory factory = SAXParserFactory.newInstance();
        SAXParser saxParser = factory.newSAXParser();
        XmlParseHandler handler = new XmlParseHandler();
        saxParser.parse(rssUrl, handler);
        return handler.getItems();
    }

}

I’m calling her on View thus:

RssReader reader = new RssReader("endereco.xml");

It needs to be done, but make the mistake

android.iosNetworkOnMainThreadException

. I saw that the solution was to use Asynctask, but I didn’t understand at least how to apply in my model, how would the implementation and the call?

Answer 1

This exception occurs, as I said very well, when trying to do an operation on the Thread main. You have to run your code in a AsyncTask:

class RetrieveFeedTask extends AsyncTask<String, Void, RssReader> {

    private Exception exception;

    protected RssReader doInBackground(String... urls) {
        try {
            SAXParserFactory factory =SAXParserFactory.newInstance();
            SAXParser saxParser=factory.newSAXParser();
            XmlParseHandler handler = new XmlParseHandler();
            saxParser.parse(urls[0], handler);
            saveInBD(handler.getItems());

        } catch (Exception e) {
            this.exception = e;
            return null;
        }
    }

    protected void onPostExecute(RssReader reader) {

    }
}

Instead of

RssReader reader = new RssReader("endereco.xml");

perform the task:

new RetrieveFeedTask().execute(urlToRssFeed);

Don’t forget to add to AndroidManifest.xml this:

<uses-permission android:name="android.permission.INTERNET"/>

^{Soen source}

Example

Answer 2

I was having the same problem, just implemented it in the onCreate method and ran normally

StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);