解决:pullToRefresh数据未充满界面bug

if(mItemCount++>15){
       mListView.setMode(PullToRefreshBase.Mode.BOTH);
}else{
       mListView.setMode(PullToRefreshBase.Mode.PULL_FROM_START); 
} 
 //将doInBackground返回的String字符串加入数据源 
     mDatas.add(s); 
//listView适配器修改数据展示
    mAdapter.notifyDataSetChanged();
//pull-to-refresh ListView 完成刷新 
    mListView.onRefreshComplete();