RuntimeException: Can't create handler inside thread that has not called Looper.prepare()

问题

I've got a code with an ASyncTask and the problem is that when I execute it several times it crashes with this exception: RuntimeException: Only one Looper may be created per thread

But then I've read this: https://stackoverflow.com/a/7781280/869180 and I remembered that I had a similar error in the past and it was related to the UI stuff (a ProgressDialog in my case) created in the ASyncTask.

So I took off all the UI stuff from the ASyncTask and I removed Looper.prepare too, to avoid that RuntimeException, but know I'm getting this:

12-21 00:34:17.363: W/System.err(18658): java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
12-21 00:34:17.371: W/System.err(18658):    at android.os.Handler.<init>(Handler.java:121)
12-21 00:34:17.371: W/System.err(18658):    at android.app.Activity.<init>(Activity.java:683)
12-21 00:34:17.371: W/System.err(18658):    at com.konex.Alaves.Parser.<init>(Parser.java:29)
12-21 00:34:17.371: W/System.err(18658):    at com.konex.Alaves.News$LoadNews.doInBackground(News.java:131)

Here is the code:

private class LoadNews extends AsyncTask<String, Void, Void> 
{
    private List<Noticia> data = new ArrayList<Noticia>();

    @Override
    protected void onPreExecute() {
        m_dialog.show();
    }

    @Override
    protected Void doInBackground(String... url) {
        try {

//          Looper.myLooper();
//          Looper.prepare();
            Parser parser = new Parser(url[0], url[1]);
            data = parser.run();

           } catch (Exception e) { 
               e.printStackTrace();
           }
        return null;
    }

@Override
    protected void onPostExecute(Void result) {

            m_dialog.dismiss();

        if(data !=null )                
            showNewContent(data);
    }
}

I'm sure I'm missing something or I am doing something bad, but I'm not able to find it anywhere.

Thanks a lot

回答1:

As the stack trace tells you, your problem originates from line 29 of Parser.java, in the Parser initializers. You will note that this is not the source code you included here, which is for LoadNews.

Based on the preceding line of the stack trace, either: