Listview不会使用带有Asynctask的notifydatasetchanged刷新数据

Question

我在AsyncTask的后台添加项目到ArrayList。在PostExecute上我创建了一个自定义适配器，我传入了ArrayList。
当我想添加更多项目时，ListView不会刷新。到目前为止，我有：

private class ProgressBlogList extends AsyncTask<String, Integer, String> {
    ProgressBar blog_progress;
    ProgressBar laProgress = new ProgressBar(getActivity(), null, android.R.attr.progressBarStyle);
    ArrayList<Integer> posts = new ArrayList<Integer>();
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        blog_lista = (ListView) getView().findViewById(R.id.blog_list);
        blog_progress = (ProgressBar) getView().findViewById(R.id.blog_progress);
        if (blog_lista.getVisibility() == View.VISIBLE) {
            blog_lista.addFooterView(laProgress);
        }
    }

    @Override
    protected String doInBackground(String... strings) {
        DatabaseHelper db = new DatabaseHelper(getActivity());
        arraydir = db.getTenItemBlogList(arraydir, id_number);
        for(int i = 0; i<arraydir.size(); i++){
            Integer post = arraydir.get(i).getId_post();
            posts.add(post);
        }
        arrayImages = db.getImagePost(posts);
        id_number = arraydir.size();

        db.close();
        return null;
    }

    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
        try {
        AdapterBlogList adapter = new AdapterBlogList(getActivity(), arraydir,arrayImages);
        blog_lista.setAdapter(adapter);
        adapter.notifyDataSetChanged();
        index = blog_lista.getFirstVisiblePosition();
        View v = blog_lista.getChildAt(0);
        top = (v == null) ? 0 : v.getTop();
        blog_lista.setVisibility(View.VISIBLE);
        blog_lista.removeFooterView(laProgress);
        blog_progress.setVisibility(View.GONE);
        }catch (Exception e) {
            Log.e(e.getMessage(), "Error IVAN::");
        }
        blog_lista.setSelectionFromTop(index, top);
        blog_lista.setOnScrollListener(new AbsListView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(AbsListView absListView, int i) {

            }

            @Override
            public void onScroll(AbsListView absListView, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
                if (firstVisibleItem + visibleItemCount == totalItemCount) {
                    if (footerProgress != null) {
                        if (footerProgress.getStatus() != Status.RUNNING) {
                            footerProgress = new ProgressBlogList();
                            footerProgress.execute();
                        }
                        }else{
                        footerProgress = new ProgressBlogList();
                        footerProgress.execute();
                    }
                }
            }
        });
        blog_lista.setSelectionFromTop(index, top);

    }
}