Android实现基于滑动的SQLite数据分页加载技术(附demo源码下载)

<menu xmlns:android="http://schemas.android.com/apk/res/android" >
 <item
 android:id="@+id/action_settings"
 android:orderincategory="100"
 android:showasaction="never"
 android:title="@string/action_settings"/>
</menu>

package com.example.testscrollsqlite;
import java.util.arraylist;
import android.app.actionbar.layoutparams;
import android.app.activity;
import android.os.bundle;
import android.view.gravity;
import android.view.menu;
import android.view.view;
import android.view.viewgroup;
import android.widget.abslistview;
import android.widget.abslistview.onscrolllistener;
import android.widget.adapter;
import android.widget.baseadapter;
import android.widget.linearlayout;
import android.widget.listview;
import android.widget.textview;
public class mainactivity extends activity implements onscrolllistener{
 private textview loadinfo;
 private listview listview;
 private linearlayout loadlayout;
 private arraylist<string> items;
 private databaseservice service;
 private int currentpage = 1; //默认在第一页
 private static final int linesize = 7; //每次显示数 
 private int allrecorders = 0; //全部记录数
 private int pagesize = 1; //默认共一页
 private int lastitem;
 private aleph0 baseadapter;
 @override
 protected void oncreate(bundle savedinstancestate) {
  super.oncreate(savedinstancestate);
  setcontentview(r.layout.activity_main);
  listview = (listview) findviewbyid(r.id.listview);
  //创建一个角标线性布局用来显示"正在加载"
  loadlayout = new linearlayout(this);
  loadlayout.setgravity(gravity.center);
  //定义一个文本显示“正在加载”
  loadinfo = new textview(this); 
  loadinfo.settext("正在加载...");
  loadinfo.setgravity(gravity.center);
  //增加组件 
  loadlayout.addview(loadinfo, new layoutparams(
    linearlayout.layoutparams.match_parent, linearlayout.layoutparams.wrap_content));
  //增加到listview底部
  listview.addfooterview(loadlayout);
  listview.setonscrolllistener(this);
  showalldata();
 }
 /**
  * 读取全部数据
  */
 public void showalldata(){
  service = new databaseservice(this);
  allrecorders = service.getcount();
  //计算总页数
  pagesize = (allrecorders + linesize -1) / linesize; 
  system.out.println("allrecorders = " + allrecorders);
  system.out.println("pagesize = " + pagesize);
  items = service.getallitems(currentpage, linesize);
  for(int i=0; i<items.size(); i++){
   system.out.println(items.get(i));
  }
  baseadapter = new aleph0();
  listview.setadapter(baseadapter);
 }
 @override
 public void onscroll(abslistview view, int firstvisible, int visiblecount,
   int totalcount) {
  lastitem = firstvisible + visiblecount - 1; //统计是否到最后
 }
 @override
 public void onscrollstatechanged(abslistview view, int scorllstate) {
  system.out.println("进入滚动界面了");
  //是否到最底部并且数据没读完
  if(lastitem == baseadapter.getcount() 
    && currentpage < pagesize //不再滚动
    && scorllstate == onscrolllistener.scroll_state_idle){
   currentpage ++;
   //设置显示位置
   listview.setselection(lastitem);
   //增加数据
   appenddate(); 
  }
 }
 /**
  * 增加数据
  */
 private void appenddate(){
  arraylist<string> additems = service.getallitems(currentpage, linesize);
  baseadapter.setcount(baseadapter.getcount() + additems.size());
  //判断，如果到了最末尾则去掉“正在加载”
  if(allrecorders == baseadapter.getcount()){
   listview.removefooterview(loadlayout);
  }
  items.addall(additems);
  //通知记录改变
  baseadapter.notifydatasetchanged();
 }
 class aleph0 extends baseadapter {
  int count = linesize; /* starting amount */
  public int getcount() {
   return count;
  } 
  public void setcount(int count){
   this.count = count;
  }
  public object getitem(int pos) {
   return pos;
  }
  public long getitemid(int pos) {
   return pos;
  }
  public view getview(int pos, view v, viewgroup p) {
   textview view = new textview(mainactivity.this);
   view.settextsize(60);
   if(items != null){
    view.settext(items.get(pos));
   }else{
    view.settext(pos);
   }
   return view;
  }
 }
}