android listview数据的分批显示
布局文件activity_call_safe2.xml
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<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<relativelayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<textview
style="@style/titlestyle"
android:text="黑名单管理"
/>
<button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignparentright="true"
android:text="添加"
/>
</relativelayout>
<framelayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="11"
>
<linearlayout
android:id="@+id/ll_pb"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:visibility="invisible"
android:orientation="vertical"
>
<progressbar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
<textview
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="玩命加载中..."
/>
</linearlayout>
<include
android:id="@+id/list_view_callsafe"
layout="@layout/list_view_callsafe"/>
</framelayout>
</linearlayout>逻辑文件，实现页面的分页显示，监听listview的滑动事件，滑动的时候就更新数据
casllsafeactivity.java
package com.ldw.safe.activity;
import java.util.list;
import android.app.activity;
import android.content.context;
import android.os.bundle;
import android.os.handler;
import android.os.message;
import android.view.view;
import android.view.view.onclicklistener;
import android.view.viewgroup;
import android.widget.abslistview;
import android.widget.abslistview.onscrolllistener;
import android.widget.edittext;
import android.widget.imageview;
import android.widget.linearlayout;
import android.widget.listview;
import android.widget.textview;
import android.widget.toast;
import com.ldw.safe.r;
import com.ldw.safe.adapter.mybaseadapter;
import com.ldw.safe.bean.blacknumberinfo;
import com.ldw.safe.db.dao.blacknumberdao;
public class callsafeactivity extends activity {
private listview list_view_callsafe;
private list<blacknumberinfo> blacknumberinfos;
private linearlayout ll_pb;
private blacknumberdao dao;
private callsafeadapter adapter;
private int totalnumber;//总的条数
private int mstartindex = 0;//开始加载的位置
private int maxcount = 20;//每页加载多少数据
@override
protected void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.activity_call_safe2);
initui();
initdata();
}
//初始化数据
private handler handler = new handler(){
@override
public void handlemessage(message msg) {
//数据初始化结束，关闭家在全的展示
ll_pb.setvisibility(view.invisible);
//防止适配器一直刷新
if(adapter == null){
adapter = new callsafeadapter(blacknumberinfos, callsafeactivity.this);
//配置适配器
list_view_callsafe.setadapter(adapter);
}else{
adapter.notifydatasetchanged();
}
}
};
private edittext et_page_number;
//初始化数据
private void initdata() {
//防止阻塞主线程，在子线程中初始化数据（后期数据会很多）
new thread(){
@override
public void run(){
dao = new blacknumberdao(callsafeactivity.this);
//一共有多少条数据
totalnumber = dao.gettotalnumber();
//分批加载数据
if(blacknumberinfos == null){
//第一次加载
blacknumberinfos = dao.findpar2(mstartindex, maxcount);
}else{
//把后面的数据。追加到blacknumberinfos集合里面。防止黑名单被覆盖
blacknumberinfos.addall(dao.findpar2(mstartindex, maxcount));
}
handler.sendemptymessage(0);
}
}.start();
}
//初始化ui
private void initui() {
ll_pb = (linearlayout) findviewbyid(r.id.ll_pb);
//初始化的时候展示加载的圆圈
ll_pb.setvisibility(view.visible);
list_view_callsafe = (listview) findviewbyid(r.id.list_view_callsafe);
//设置listview的滚动监听器
list_view_callsafe.setonscrolllistener(new onscrolllistener(){
//状态改变时候回调的方法
/*
* @param scrollstate 表示滚动的状态
*abslistview.onscrolllistener.scroll_state_idle 闲置状态
*abslistview.onscrolllistener.scroll_state_touch_scroll 手指触摸的时候的状态
*abslistview.onscrolllistener.scroll_state_fling 惯性
*/
@override
public void onscrollstatechanged(abslistview view, int scrollstate) {
switch (scrollstate) {
case abslistview.onscrolllistener.scroll_state_idle:
//获取到最后一条显示的数据条数
int lastvisibleposition = list_view_callsafe.getlastvisibleposition();
system.out.println("lastvisibleposition==========" + lastvisibleposition);
if(lastvisibleposition == blacknumberinfos.size() - 1){//判断最后一个数据是不是每页显示的数据-1
// 加载更多的数据。 更改加载数据的开始位置
mstartindex += maxcount;
if (mstartindex >= totalnumber) {
toast.maketext(getapplicationcontext(),
"没有更多的数据了。", toast.length_short).show();
return;
}
initdata();
}
break;
}
}
//listview滚动的时候调用的方法
//时时调用。当我们的手指触摸的屏幕的时候就调用
@override
public void onscroll(abslistview view, int firstvisibleitem,
int visibleitemcount, int totalitemcount) {
// todo auto-generated method stub
}
});
}
//对代码进行优化，继承自定义mybaseadapter，mybaseadapter继承自baseadapter封装一些常用的方法
private class callsafeadapter extends mybaseadapter<blacknumberinfo>{
private callsafeadapter(list lists, context mcontext){
super(lists, mcontext);
}
@override
public view getview(int position, view convertview, viewgroup parent) {
//谷歌推出的优化方案
viewholder holder;
if(convertview == null){
convertview = view.inflate(callsafeactivity.this, r.layout.item_call_safe, null);
holder = new viewholder();
holder.tv_number = (textview) convertview.findviewbyid(r.id.tv_number);
holder.tv_mode = (textview) convertview.findviewbyid(r.id.tv_mode);
holder.iv_delete = (imageview) convertview.findviewbyid(r.id.iv_delete);
convertview.settag(holder);
}else{
holder = (viewholder) convertview.gettag();
}
holder.tv_number.settext(lists.get(position).getnumber());
string mode = lists.get(position).getmode();
if(mode.equals("1")){
holder.tv_mode.settext("电话和短信拦截");
}else if(mode.equals("2")){
holder.tv_mode.settext("电话拦截");
}else if(mode.equals("3")){
holder.tv_mode.settext("短信拦截");
}
final blacknumberinfo info = lists.get(position);
//监听删除数据按钮，删除数据
holder.iv_delete.setonclicklistener(new onclicklistener(){
@override
public void onclick(view v) {
string number = info.getnumber();
boolean result = dao.delete(number);
if(result){
toast.maketext(callsafeactivity.this, "删除成功", toast.length_short).show();
lists.remove(info);
//更新listview
adapter.notifydatasetchanged();
}else{
toast.maketext(callsafeactivity.this, "删除失败", toast.length_short).show();
}
}
});
return convertview;
/*
//谷歌推出的优化方案
viewholder holder;
if(convertview == null){
convertview = view.inflate(callsafeactivity.this, r.layout.item_call_safe, null);
holder = new viewholder();
holder.tv_number = (textview) convertview.findviewbyid(r.id.tv_number);
holder.tv_mode = (textview) convertview.findviewbyid(r.id.tv_mode);
convertview.settag(holder);
}else{
holder = (viewholder) convertview.gettag();
}
holder.tv_number.settext(blacknumberinfos.get(position).getnumber());
string mode = blacknumberinfos.get(position).getmode();
if(mode.equals("1")){
holder.tv_mode.settext("电话和短信拦截");
}else if(mode.equals("2")){
holder.tv_mode.settext("电话拦截");
}else if(mode.equals("3")){
holder.tv_mode.settext("短信拦截");
}
return convertview;
*/
/*初步的优化
convertview = view.inflate(callsafeactivity.this, r.layout.item_call_safe, null);
textview tv_number = (textview) convertview.findviewbyid(r.id.tv_number);
textview tv_mode = (textview) convertview.findviewbyid(r.id.tv_mode);
tv_number.settext(blacknumberinfos.get(position).getnumber());
string mode = blacknumberinfos.get(position).getmode();
if(mode.equals("1")){
tv_mode.settext("电话和短信拦截");
}else if(mode.equals("2")){
tv_mode.settext("电话拦截");
}else if(mode.equals("3")){
tv_mode.settext("短信拦截");
}
return convertview;
*/
/*传统的方式
view view = view.inflate(callsafeactivity.this, r.layout.item_call_safe, null);
textview tv_number = (textview) view.findviewbyid(r.id.tv_number);
textview tv_mode = (textview) view.findviewbyid(r.id.tv_mode);
tv_number.settext(blacknumberinfos.get(position).getnumber());
string mode = blacknumberinfos.get(position).getmode();
if(mode.equals("1")){
tv_mode.settext("电话和短信拦截");
}else if(mode.equals("2")){
tv_mode.settext("电话拦截");
}else if(mode.equals("3")){
tv_mode.settext("短信拦截");
}
return view;
*/
}
}
static class viewholder{
textview tv_number;
textview tv_mode;
imageview iv_delete;
}
}
以上所述是小编给大家介绍的android listview数据的分批显示功能，希望对大家有所帮助
如对本文有疑问， 点击进行留言回复！！
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