Android使用ListView实现下拉刷新及上拉显示更多的方法

packagecom.stay.main;

importjava.net.HttpURLConnection;

importjava.util.ArrayList;

importjava.util.HashMap;

importorg.json.JSONObject;

importandroid.app.Activity;

importandroid.app.ProgressDialog;

importandroid.graphics.drawable.Drawable;

importandroid.os.Bundle;

importandroid.os.Handler;

importandroid.os.HandlerThread;

importandroid.os.Looper;

importandroid.os.Message;

importandroid.view.LayoutInflater;

importandroid.view.View;

importandroid.widget.AbsListView;

importandroid.widget.AbsListView.OnScrollListener;

importandroid.widget.Button;

importandroid.widget.LinearLayout;

importandroid.widget.ListView;

importandroid.widget.RelativeLayout;

importandroid.widget.TextView;

importcom.stay.wifi.R;

/**

* @author Stay

* 动态加载listview数据，上拉 刷新，下拉 更多

*/

publicclassListViewActivityextendsActivityimplementsOnScrollListener {

privatestaticfinalintLOAD =0;

privatestaticfinalintERROR =0;

privatestaticfinalintMEMBER =1;

privatestaticfinalintLOADED =2;

privatestaticfinalintDIALOG =3;

privatestaticfinalintFULL =4;

privateNearbyAdapter adapter;

privateListView nearby_lv;

privateRelativeLayout nearby_lv_header;

privateButton list_bottom_btn;

privateLinearLayout list_bottom_linear;

privateTextView bottom_progress_text;

privateRelativeLayout nearby_lv_footer;

privateButton list_header_btn;

privateLinearLayout list_header_linear;

privateTextView heard_progress_text;

privateArrayListnearby_data =newArrayList();

privateintlastItem;

privateHashMapimageCache;

privatecom.stay.main.ListViewActivity.MyHandler myHandler;

privateProgressDialog dialog;

privateintcurPage =1;

privatebooleanisMember =false;

privateintfirstItem;

publicintcount;

/** Called when the activity is first created. */

@Override

publicvoidonCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

initView();

myHandler.sendEmptyMessage(LOAD);

}

@Override

publicvoidonScrollStateChanged(AbsListView view,intscrollState) {

DebugUtil.debug("onScrollStateChanged");

//当滚动停止且滚动的总数等于数据的总数，去加载

if(lastItem == count && scrollState == SCROLL_STATE_IDLE) {

DebugUtil.debug("onScrollStateChanged--------next");

if(curPage ==4&& !isMember) {

DebugUtil.show(this,"您不是正式会员，请申请正式会员，");

list_bottom_linear.setVisibility(View.GONE);

}else{

//加载数据

myHandler.sendEmptyMessage(LOAD);

}

return;

}

//当往上拉时更新数据，将data清空然后去重新加载

if(firstItem ==0&& scrollState == SCROLL_STATE_IDLE) {

DebugUtil.debug("onScrollStateChanged--------refresh");

curPage =0;

myHandler.sendEmptyMessage(LOAD);

}

}

@Override

publicvoidonScroll(AbsListView view,intfirstVisibleItem,intvisibleItemCount,inttotalItemCount) {

DebugUtil.debug("firstVisibleItem="+ firstVisibleItem);

DebugUtil.debug("visibleItemCount="+ visibleItemCount);

DebugUtil.debug("totalItemCount="+ totalItemCount);

//这里要减二，因为我加了header footer

lastItem = firstVisibleItem + visibleItemCount -2;

firstItem = firstVisibleItem;

}

publicintgetData() {

try{

HttpURLConnection conn = DownloadUtil.download(url//自己写咯);

ArrayListtemp = JSONUtil.streamToJsonList(conn.getInputStream());

if(curPage ==0&& nearby_data.size() >0) {

nearby_data.clear();

count =0;

}

if(temp !=null&& temp.size() >0) {

count += temp.size();

nearby_data.addAll(temp);

DebugUtil.debug("nearby_data.size()="+nearby_data.size());

}else{

returnFULL;

}

returnLOADED;

}catch(Exception e) {

returnERROR;

}

}

privateHandler handler =newHandler() {

@Override

publicvoidhandleMessage(Message msg) {

super.handleMessage(msg);

switch(msg.what) {

caseDIALOG:

list_bottom_linear.setVisibility(View.VISIBLE);

list_header_linear.setVisibility(View.VISIBLE);

break;

caseLOADED:

list_bottom_linear.setVisibility(View.GONE);

list_header_linear.setVisibility(View.GONE);

curPage++;

adapter.notifyDataSetChanged();

break;

caseERROR:

DebugUtil.debug("error,missing data");

break;

caseMEMBER:

DebugUtil.debug("you must regist formal member");

break;

default:

break;

}

}

};

//创建子线程加载数据，然后更新

privateclassMyHandlerextendsHandler {

privateintstatus;

publicMyHandler(Looper looper) {

super(looper);

}

@Override

publicvoidhandleMessage(Message msg) {

synchronized(this) {

switch(msg.what) {

caseLOAD:// get data from server

handler.sendEmptyMessage(DIALOG);//显示等待框

status = getData();

handler.sendEmptyMessageDelayed(status,1000);

break;

default:

break;

}

}

}

}

publicvoidinitView() {

imageCache =newHashMap();

HandlerThread handlerThread =newHandlerThread("nearby");

// 在使用HandlerThread的getLooper()方法之前，必须先调用该类的start();

handlerThread.start();

myHandler =newMyHandler(handlerThread.getLooper());

nearby_lv = (ListView) findViewById(R.id.nearby_lv);

nearby_lv_footer = (RelativeLayout) LayoutInflater.from(ListViewActivity.this).inflate(R.layout.nearby_lv_header,null);

list_bottom_btn = (Button) nearby_lv_footer.findViewById(R.id.list_bottom_btn);

list_bottom_linear = (LinearLayout) nearby_lv_footer.findViewById(R.id.list_bottom_linear);

bottom_progress_text = (TextView) nearby_lv_footer.findViewById(R.id.progress_text);

nearby_lv_header = (RelativeLayout) LayoutInflater.from(ListViewActivity.this).inflate(R.layout.nearby_lv_header,null);

list_header_btn = (Button) nearby_lv_header.findViewById(R.id.list_bottom_btn);

list_header_linear = (LinearLayout) nearby_lv_header.findViewById(R.id.list_bottom_linear);

heard_progress_text = (TextView) nearby_lv_header.findViewById(R.id.progress_text);

list_header_btn.setText("刷新");

list_bottom_btn.setText("更多");

list_header_linear.setVisibility(View.GONE);

nearby_lv.addHeaderView(nearby_lv_header);

nearby_lv.addFooterView(nearby_lv_footer);

// list_header_btn.setOnClickListener(header_click);

adapter =newNearbyAdapter(ListViewActivity.this, nearby_data);

nearby_lv.setAdapter(adapter);

nearby_lv.setOnScrollListener(ListViewActivity.this);

}

}