title: Android dynamic loading list view onScrollListener issues
body: <p>I have implemented a list view, every user scroll to bottom screen, it auto add new data to list view
  Once the scroll has completed, onScroll() call for every new item that enters the displaying view, from the beginning to the end of the scrolling.</p>
  
  <pre><code>lv_best = (ListView) findViewById(R.id.lv_best);
  bestadapter = new LazyAdapter(this, lst_tab_best);
  lv_best.setAdapter(bestadapter);
  lv_best.setOnScrollListener(new AbsListView.OnScrollListener() {
  
      @Override
      public void onScrollStateChanged(AbsListView view, int scrollState) { }
  
      @Override
      public void onScroll(AbsListView view, int firstVisibleItem,
                          int visibleItemCount, int totalItemCount) {
  
      Log.d("onScroll ", firstVisibleItem+"-"+visibleItemCount+"-"+totalItemCount);
      boolean loadMore = firstVisibleItem + visibleItemCount &gt;= totalItemCount;
      if(loadMore){
              new ChangeTab_best().execute();
       }
       }
      });
  </code></pre>
  
  <p>I run in emulator, list above display with 5 items
  but I can't detect the end of scrolling in a ListView, ChangeTab_best() is called many time.When I see Logcat android , all variables firstVisibleItem,visibleItemCount,totalItemCount always equal 0</p>
  
  <p>So what's happen here? </p>