Question

I have an AsyncTask which loads Tweets from Twitter.
I also have a PullToRefresh ListView… Whenever i pull to refresh it, the listview immediately clears and as soon as the data has been loaded, it’s getting filled into the listview.

I have other ListViews in my App all with the same stuff (PullToRefresh and Async data loading…). On the other ListViews this does not happen. Only on the Twitter ListView. What am I doing wrong?

Here is my Code:

    public class TwitterDownloader extends AsyncTask<Void, Void, String> {

    final Handler mHandler = new Handler();

    public TwitterDownloader() {
    }

    @Override
    public void onPreExecute() {
        super.onPreExecute();
    }

    @Override
    protected String doInBackground(Void... params) {
        twitter4j.Twitter twitter = new TwitterFactory().getInstance();

        listTweets.clear();

            List<twitter4j.Status> statuses = null;

            try {
                statuses = twitter.getUserTimeline(
                        MainActivity.TWITTER_USERNAME, new Paging(1, 50));
            } catch (TwitterException e) {
                e.printStackTrace();
                Log.e(MainActivity.LOG_TAG, "TwitterException");
            }

            try {
                for (twitter4j.Status status : statuses) {
                    listTweets.add(status.getText());
                }
            } catch (NullPointerException npe) {
            }
        return null;
    }

    @Override
    public void onPostExecute(String unused) {
        MyCustomAdapter myAdapter = new MyCustomAdapter(myContext,
                R.layout.row_twitter, listTweets);
        setListAdapter(myAdapter);
        getListView().setTextFilterEnabled(true);

        String lastUpdate = (new SimpleDateFormat(
                "HH:mm")).format(new Date());

        pullToRefreshView.onRefreshComplete();
        pullToRefreshView.setLastUpdatedLabel(getString(R.string.last_updated) + ": "
                + lastUpdate);
    }

Answer 1

I finally fixed it by adding all my clear() statements right before I fill up my list again (which is inside a try catch).

So the new code inside my doInBackground method is:

try {
            listTweets.clear();
            listUsernames.clear();
            listDates.clear();
            listImageURLs.clear();
            listURLsOfTweets.clear();
            for (twitter4j.Status status : statuses) {
                listTweets.add(status.getText());
                listUsernames.add(status.getUser().getName());
                listDates.add(android.text.format.DateFormat
                        .getDateFormat(getApplicationContext()).format(
                                status.getCreatedAt())
                        + " "
                        + android.text.format.DateFormat.getTimeFormat(
                                getApplicationContext()).format(
                                status.getCreatedAt()));
                listImageURLs.add(status.getUser().getProfileImageURL()
                        .toString());

                StringBuffer address = new StringBuffer();
                address.append("http://twitter.com/#!/");
                address.append(status.getUser().getScreenName());
                address.append("/status/");
                address.append(status.getId());

                listURLsOfTweets.add(address.toString());
}