Question

I want to fill a ListFragment with certain objects loaded from my MySql database.

It has to load the first 10 ‘objects’ from my ResultSet.
I want to use an AsyncTaskLoader for this and put the loaded object in a ListItem each time I retreive it from the database.

Can anybody help me with this one? Tried searching for good examples or tutorials but I haven’t really found something that’s really useful…

Answer 1

Create your adapter with a new list in your preexecute method. Set that adapter to your listview.

Then in doInBackground read your database, create objects to fit in your list, but don’t add them. Pas each object after made as parameter for your publishprogress method.

In onProgressUpdate add your object to the list and notify your adapter that the dataset is changed.

Below is an example for how I do it reading a twitter call.

private class parseTwitterTask extends AsyncTask<Void, TCListObject2, List<TCListObject2>> {
    TCListObjectAdapter2 adapter;
    List<TCListObject2> list;

    @Override
    protected void onPreExecute() {
        list = new ArrayList<TCListObject2>();
        ListView lv = (ListView)findViewById(R.id.twitterlist);
        adapter = new TCListObjectAdapter2(list);
        lv.setAdapter(adapter);
        super.onPreExecute();
    }

    @Override
    protected List<TCListObject2> doInBackground(Void... params) {
        try {
            String url = social.get("twittersearchurl");//"http://search.twitter.com/search.json?q=" + social.get("twitter");
            String json = Internet.request(url, null);
            JSONObject jo = new JSONObject(json);
            if(jo.has("results")) {                 
                JSONArray ar = jo.getJSONArray("results");
                for(int i = 0; i < ar.length(); i++) {
                    TCListObject2 tweet = new TCListObject2();
                    JSONObject jobj = (JSONObject) ar.get(i);
                    tweet.id = "false";
                    tweet.img = jobj.getString("profile_image_url");

                    String text = jobj.getString("text");
                    text = Html.fromHtml(text).toString();
                    tweet.params.put(R.id.sub2, text);

                    String name = jobj.getString("from_user");
                    name = Html.fromHtml(name).toString();
                    tweet.params.put(R.id.text, name);

                    String time = jobj.getString("created_at");
                    tweet.params.put(R.id.sub1, Converter.timeToTimeAgo(time));

                    try {
                        tweet.time = new Date(time);
                    } catch(Exception e) {
                        e.printStackTrace();
                    }

                    tweet.celLayout = R.layout.cell_tweetobject;
                    publishProgress(tweet);
                }
            }
        } catch(Exception e) {
            e.printStackTrace();
        }

        return list;
    }

    @Override
    protected void onProgressUpdate(TCListObject2... values) {
        list.add(values[0]);
        adapter.notifyDataSetChanged();
        super.onProgressUpdate(values);
    }