获取tabhost的当前view，并从中取出list，刷新

if (tabHost.getCurrentTabTag().equals("tab2")) {             LinearLayout listLayout = (LinearLayout) tabHost                 .getCurrentView().findViewById(                     R.id.downloadmanage_linearlayou);             Adapter_Download_list downloadList = (Adapter_Download_list) listLayout                 .getChildAt(0);             downloadList.refreshListData();         }