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POPopulating a ListView w/ AsyncTask
 

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    <p>This is probably not very elegant, but what I'm trying to do is connect to a web service, fetch the JSON, parse it, create an object out of it, add that object to an ArrayList and then use that ArrayList to populate my ListView. </p> <p>I'm trying to do all of this with AsyncTask.</p> <p>SUMMARY: doInBackgroud takes a String of a url, uses it to connect to a web service. I get the JSON data as a string, parse it, construct a new object out of the data, and add it to ArrayList. Then in <code>onPostExecute</code> I'm trying to set the listadapter using an <code>ArrayAdapter</code> that utilizes my ArrayList.</p> <p>Here's what I have:</p> <pre><code>import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.Reader; import java.io.StringWriter; import java.io.Writer; import java.net.HttpURLConnection; import java.net.URL; import java.util.ArrayList; import java.util.Arrays; import org.json.JSONArray; import org.json.JSONObject; import oauth.signpost.OAuthConsumer; import oauth.signpost.basic.DefaultOAuthConsumer; import android.app.ListActivity; import android.app.ProgressDialog; import android.os.AsyncTask; import android.os.Bundle; import android.widget.ArrayAdapter; public class AllOffersListActivity extends ListActivity { private static final String CONSUMER_KEY = "bla"; private static final String CONSUMER_SECRET = "bla"; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); new CreateArrayListTask().execute("http://example.com/sample.json"); } private class CreateArrayListTask extends AsyncTask&lt;String, Void, ArrayList&lt;Offer&gt;&gt; { private final ProgressDialog dialog = new ProgressDialog(AllOffersListActivity.this); @Override protected void onPreExecute() { this.dialog.setMessage("Fetching offers..."); this.dialog.show(); } @Override protected ArrayList&lt;Offer&gt; doInBackGround(String...urls) { ArrayList&lt;Offer&gt; offerList = new ArrayList&lt;Offer&gt;(); for(String url: urls) { OAuthConsumer consumer = new DefaultOAuthConsumer(CONSUMER_KEY, CONSUMER_SECRET); consumer.setTokenWithSecret("", ""); try { URL url1 = new URL(url); HttpURLConnection request = (HttpURLConnection) url1.openConnection(); // sign the request consumer.sign(request); // send the request request.connect(); String JSONString = convertStreamToString(request.getInputStream()); JSONObject jObject = new JSONObject(JSONString); JSONObject offerObject = jObject.getJSONObject("offer"); String titleValue = offerObject.getString("title"); //System.out.println(titleValue); String descriptionValue = offerObject.getString("description"); //System.out.println(attributeValue); JSONObject businessObject = offerObject.getJSONObject("business"); String nameValue = businessObject.getString("name"); Offer myOffer = new Offer(titleValue, descriptionValue, nameValue); offerList.add(myOffer); } catch (Exception e) { e.printStackTrace(); } } return offerList; } @Override protected void onPostExecute(ArrayList&lt;Offer&gt; offerList) { if(this.dialog.isShowing()) this.dialog.dismiss(); setListAdapter(new ArrayAdapter&lt;Offer&gt;(AllOffersListActivity.this, android.R.layout.simple_list_item_1, offerList)); } } private String convertStreamToString(InputStream inputStream) throws IOException { if(inputStream != null) { Writer writer = new StringWriter(); char[] buffer = new char[1024]; try { Reader reader = new BufferedReader( new InputStreamReader(inputStream, "UTF-8")); int n; while((n = reader.read(buffer)) != -1) { writer.write(buffer, 0, n); } } finally { inputStream.close(); } return writer.toString(); } else { return ""; } } } </code></pre> <p>I'm seeing two errors. One is on my private Async class: <code>"The type AllOffersListActivity.CreateArrayListTask must implement the inherited abstract method AsyncTask&lt;String,Void,ArrayList&lt;Offer&gt;&gt;.doInBackground(String...)"</code></p> <p>Secondly, on my <code>doInBackGround</code> Override, I'm getting: <code>The method doInBackGround(String...) of type AllOffersListActivity.CreateArrayListTask must override or implement a supertype method</code></p> <p>What am I missing here?</p>
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