Android使用ListView实现下拉刷新及上拉显示更多的方法
本文实例讲述了Android使用ListView实现下拉刷新及上拉显示更多的方法。分享给大家供大家参考，具体如下：
今天得需求是做listview+上下拉动在header和footer显示progressdialog，但不影响用户操作
直接上代码，我已经加上注释了，自己看。
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;
/**
*@authorStay
*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;
privateNearbyAdapteradapter;
privateListViewnearby_lv;
privateRelativeLayoutnearby_lv_header;
privateButtonlist_bottom_btn;
privateLinearLayoutlist_bottom_linear;
privateTextViewbottom_progress_text;
privateRelativeLayoutnearby_lv_footer;
privateButtonlist_header_btn;
privateLinearLayoutlist_header_linear;
privateTextViewheard_progress_text;
privateArrayList<JSONObject>nearby_data=newArrayList<JSONObject>();
privateintlastItem;
privateHashMap<String,Drawable>imageCache;
privatecom.stay.main.ListViewActivity.MyHandlermyHandler;
privateProgressDialogdialog;
privateintcurPage=1;
privatebooleanisMember=false;
privateintfirstItem;
publicintcount;
/**Calledwhentheactivityisfirstcreated.*/
@Override
publicvoidonCreate(BundlesavedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
initView();
myHandler.sendEmptyMessage(LOAD);
}
@Override
publicvoidonScrollStateChanged(AbsListViewview,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(AbsListViewview,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headerfooter
lastItem=firstVisibleItem+visibleItemCount-2;
firstItem=firstVisibleItem;
}
publicintgetData(){
try{
HttpURLConnectionconn=DownloadUtil.download(url//自己写咯);
ArrayList<JSONObject>temp=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(Exceptione){
returnERROR;
}
}
privateHandlerhandler=newHandler(){
@Override
publicvoidhandleMessage(Messagemsg){
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,missingdata");
break;
caseMEMBER:
DebugUtil.debug("youmustregistformalmember");
break;
default:
break;
}
}
};
//创建子线程加载数据，然后更新
privateclassMyHandlerextendsHandler{
privateintstatus;
publicMyHandler(Looperlooper){
super(looper);
}
@Override
publicvoidhandleMessage(Messagemsg){
synchronized(this){
switch(msg.what){
caseLOAD://getdatafromserver
handler.sendEmptyMessage(DIALOG);//显示等待框
status=getData();
handler.sendEmptyMessageDelayed(status,1000);
break;
default:
break;
}
}
}
}
publicvoidinitView(){
imageCache=newHashMap<String,Drawable>();
HandlerThreadhandlerThread=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);
}
}
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