Method Execute In Asynctask Does Not Work With String

I try to execute an AsyncTask like this private static final String REQUESTED_URL = '//my url'; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(

Solution 1:

Your class signature suggests that you are expecting a URL type as parameter, but you are passing a String type in the execute() method. All you need to do is to change your class signature to expect a String as in the one in this code.

privateclassEarthQuakeAsyncTaskextendsAsyncTask<String,Void,ArrayList<EarthQuake>> {
        @Overrideprotected ArrayList<EarthQuake> doInBackground(String... urls) {
            if(urls.length==0||urls[0]== null){
                returnnull;
            }
            // Create a URL object from the String passed to the execute methodURLurl= createUrl(urls[0]);
            try {
                jsonResponse = makeHttpRequest(url);
            } catch (IOException e) {
                // TODO Handle the IOException
            }
            ArrayList<EarthQuake> earthquake = QueryUtils.extractEarthquakes(jsonResponse);
            return earthquake;
        }

        @OverrideprotectedvoidonPostExecute(ArrayList<EarthQuake> earthquake) {
            if (earthquake == null) {
                return;
            }
            updateUi();
        }


        private URL createUrl(String stringUrl) {
            URL url;
            try {
                url = newURL(stringUrl);
            } catch (MalformedURLException exception) {
                Log.e(LOG_TAG, "Error with creating URL", exception);
                returnnull;
            }
            return url;
        }

        private String makeHttpRequest(URL url)throws IOException {
            // If the URL is null, then return early.if (url == null) {
                return jsonResponse;
            }

            HttpURLConnectionurlConnection=null;
            InputStreaminputStream=null;
            try {
                urlConnection = (HttpURLConnection) url.openConnection();
                urlConnection.setReadTimeout(10000/* milliseconds */);
                urlConnection.setConnectTimeout(15000/* milliseconds */);
                urlConnection.setRequestMethod("GET");
                urlConnection.connect();
                // If the request was successful (response code 200),// then read the input stream and parse the response.if (urlConnection.getResponseCode() == 200) {
                    inputStream = urlConnection.getInputStream();
                    jsonResponse = readFromStream(inputStream);
                } else {
                    Log.e(LOG_TAG, "Error response code: " + urlConnection.getResponseCode());
                }
            } catch (IOException e) {
                Log.e(LOG_TAG, "Problem retrieving the earthquake JSON results.", e);
            } finally {
                if (urlConnection != null) {
                    urlConnection.disconnect();
                }
                if (inputStream != null) {
                    inputStream.close();
                }
            }
            return jsonResponse;
        }

        private String readFromStream(InputStream inputStream)throws IOException {
            StringBuilderoutput=newStringBuilder();
            if (inputStream != null) {
                InputStreamReaderinputStreamReader=newInputStreamReader(inputStream, Charset.forName("UTF-8"));
                BufferedReaderreader=newBufferedReader(inputStreamReader);
                Stringline= reader.readLine();
                while (line != null) {
                    output.append(line);
                    line = reader.readLine();
                }
            }
            return output.toString();
        }
    }
    }

Solution 2:

That is because your AsyncTask class isn't defined in a manner to handle the execute method with a String parameter. Let me explain myself.

The AsyncTask class you develop will look like this:

privateclassMyAsyncTaskextendsAsyncTask<TYPE1, TYPE2, TYPE3> {

     protectedTYPE3doInBackground(TYPE1... type1_variables) {
         // Do some long process here..return variable_of_type_TYPE3;
     }

     protectedvoidonPostExecute(TYPE3 result) {
         // Do something here
     }
 }

So for you to call task.execute(REQUESTED_URL); you'd need to implement your AsyncTask class correctly.

For example it might look like this:

privateclassEarthQuakeAsyncTaskextendsAsyncTask<String, Void, Void> {
     ...
}