【android】如何定位listview中的某一项item呢

布局是PullToRefreshScrollView里面包含一个ListView，该怎么定位listview中的某一项item呢,下面贴出一段代码

 @Override
 protected void onPostExecute(InterestThemeReplyBean result) {
        if (result != null) {
            pageCount = result.getPageCount();
            if (actionFlag == 0) {
                reply_list.clear();
            }
            if (result.getError() == 0) {
                if (result.getResult() != null) {
                    for (int i = 0; i < result.getResult().size(); i++) {
                        InterestThemeReplyResultBean tBean = result.getResult().get(i);
                        reply_list.add(tBean);
                    }
                    ListViewForScrollView.setListViewHeightBaseOnChildren(tListview);
                    adapter.notifyDataSetChanged();

                    if (replyId != 0) {
                        LogUtil.e("Tag", replyId + "--------replyId--------");
                        for (int i = 0; i < reply_list.size(); i++) {
                            LogUtil.e("Tag", reply_list.get(i).getReplyId() + "--------reply_list.get(i).getReplyId()--------");
                            if (reply_list.get(i).getReplyId() == replyId) {
                                position = i;
                                LogUtil.e("Tag", position + "--------i--------");
                            }
                        }
                        tListview.setSelection(position);
                        adapter.notifyDataSetChanged();
                    }


                } else {
                    tv_none_discuss.setVisibility(View.VISIBLE);
                    ll_listview.setVisibility(View.GONE);
                }
            }
        } else {
            LogUtil.e("Tag", "贴子列表");
            Toast.makeText(InterestThemeDetailActivity.this, "网络超时", Toast.LENGTH_SHORT).show();
        }
        pScrollview.onRefreshComplete();

        QrProgressDialog.removeProgressDialog(InterestThemeDetailActivity.this);

        super.onPostExecute(result);
    }