using AsyncTask to display data in ListView

Question

I need me a little help. I need to use asynctask to display data in ListView. But I don\'t know how becouse I\'m new in Android programming ... thank you ve

Answer 1

Try this

new MyAsyncTask.execute("http://10.10.10.10/data.php");

Declare the task as

class MyAsyncTask extends AsyncTask<String, Integer, ArrayList<HashMap<String, String>> > {

    ArrayList<HashMap<String, String>> mylist = new ArrayList<HashMap<String, String>>();

    @Override
    protected ArrayList<HashMap<String, String>> doInBackground(String... params) {

        JSONObject json = JSONfunctions.getJSONfromURL(params[0]);

        try {
            JSONArray  ip = json.getJSONArray("ip");

            for (int i=0;i<ip.length();i++) {                     
                HashMap<String, String> map = new HashMap<String, String>();    
                JSONObject e = ip.getJSONObject(i);

                map.put("id",  String.valueOf(i));
                map.put("data1", e.getString("date"));
                map.put("data2", "Location:" +  e.getString("location") + "   Status:" + e.getString("status"));
                mylist.add(map);            
            } 
            return mylist
        } catch (JSONException e) {
            Log.e("log_tag", "Error parsing data "+e.toString());
        }
        return null;
    }

    @Override
    protected void onPostExecute(ArrayList<HashMap<String, String>> result) {
        ListAdapter adapter = new SimpleAdapter(YourActivity.this, result , R.layout.main, 
                new String[] { "data1", "data2" }, 
                new int[] { R.id.item_title, R.id.item_subtitle });
        YourActivity.this.setListAdapter(adapter); // If Activity extends ListActivity
        final ListView lv = getListView();
        lv.setTextFilterEnabled(true);

    }

Hope it helps.

Answer 2

Do not download any data in your onCreate() - if it takes too long then you will get ANR exception (Activity Not Responding). You should use AsyncTask as in your question. For AsyncTask you have very good example on android site:

http://developer.android.com/reference/android/os/AsyncTask.html

you should put JSONfunctions.getJSONfromURL() inside doInBackground()

and all whats below in onPostExecute()