AsyncTask无法在4.0.4上运行

Vla*_*mir 2 compatibility android android-asynctask

我创建了一个下面的类,它上网并向php脚本发送请求.AsyncTask为了在4.0.4上工作,我创建了它而不是在主线程中创建它,但是当我测试它时它不起作用,虽然它在2.2上工作正常.你知道这是什么问题吗?

class download extends AsyncTask<String, Integer, String> {

        protected String doInBackground(String s1, String s2) {
            String result = "";
            //http post

            ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
            nameValuePairs.add(new BasicNameValuePair("Vreme", s1));
            nameValuePairs.add(new BasicNameValuePair("Datum", s2));

            InputStream is = null;
            try {

                String adresa = "http://senzori.open.telekom.rs/script.php";
                HttpPost httppost = new HttpPost(adresa);
                httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                HttpClient httpclient = new DefaultHttpClient();

                HttpResponse response = httpclient.execute(httppost);
                HttpEntity entity = response.getEntity();
                is = entity.getContent();
            } catch (Exception e) {
                Log.e("log_tag", "Error in http connection " + e.toString());
            }
            //convert response to string
            try {
                BufferedReader reader = new BufferedReader(new InputStreamReader(is, "iso-8859-1"), 8);
                StringBuilder sb = new StringBuilder();
                String line = null;
                while ((line = reader.readLine()) != null) {
                    sb.append(line + "\n");
                }
                is.close();

                result = sb.toString();

            } catch (Exception e) {
                Log.e("log_tag", "Error converting result " + e.toString());
            }
            return result;
        }

        @Override
        protected String doInBackground(String... params) {
            // TODO Auto-generated method stub
            return null;
        }
    }
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A--*_*--C 7

它可能不起作用,因为你重载了doInBackground,但没有调用重载方法.

改变它,所以原始方法是这样的:

@Override
protected String doInBackground(String... params) {

    return doInBackground (params[0], params[1]);
}
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请注意,它现在使重载无效,将代码移回覆盖doInBackground (String... params),并且还需要确保在调用时execute(),提供两个字符串作为参数.