如何用Android实现listview分页

import java.util.Collections; 
import java.util.List; 
/** 
 * 注意所有序号从1开始. 
 * 
 * @param  Page中记录的类型. 
 * 
 */ 
public class Page { 
  //-- 公共变量 --// 
  public static final String ASC = "asc"; 
  public static final String DESC = "desc"; 
  //-- 分页参数 --// 
  protected int pageNo = 0;// 当前页号 
  protected int pageSize = 1;// 每页显示的记录数 
  protected String orderBy = null; 
  protected String order = null; 
  protected boolean autoCount = true; 
  //-- 返回结果 --// 
  protected List result = Collections.emptyList(); 
  protected long totalCount = -1;// 总记录数 
  //-- 构造函数 --// 
  public Page() { 
  } 
  public Page(final int pageSize) { 
    setPageSize(pageSize); 
  } 
  public Page(final int pageSize, final boolean autoCount) { 
    setPageSize(pageSize); 
    setAutoCount(autoCount); 
  } 
  //-- 访问查询参数函数 --// 
  /** 
   * 获得当前页的页号,序号从0开始,默认为0. 
   */ 
  public int getPageNo() { 
    return pageNo; 
  } 
  /** 
   * 设置当前页的页号,序号从0开始,低于0时自动调整为0. 
   */ 
  public void setPageNo(final int pageNo) { 
    this.pageNo = pageNo; 
    if (pageNo  getResult() { 
    return result; 
  } 
  /** 
   * 设置页内的记录列表. 
   */ 
  public void setResult(final List result) { 
    this.result = result; 
  } 
  /** 
   * 取得总记录数, 默认值为-1. 
   */ 
  public long getTotalCount() { 
    return totalCount; 
  } 
  /** 
   * 设置总记录数. 
   */ 
  public void setTotalCount(final long totalCount) { 
    this.totalCount = totalCount; 
  } 
  /** 
   * 根据pageSize与totalCount计算总页数, 默认值为-1. 
   */ 
  public long getTotalPages() { 
    if (totalCount  0) { 
      count++; 
    } 
    return count; 
  } 
  /** 
   * 是否还有下一页. 
   */ 
  public boolean isHasNext() { 
    return (pageNo + 1 = 0); 
  } 
  /** 
   * 取得上页的页号, 序号从1开始. 
   * 当前页为首页时返回首页序号. 
   */ 
  public int getPrePage() { 
    if (isHasPre()) 
      return pageNo - 1; 
    else 
      return pageNo; 
  } 
}

public class Record { 
  private Integer rId; 
  private String fromUser; 
  private String toUser; 
  private String content; 
  private String rTime; 
  private Integer isReaded; 
  public Integer getrId() { 
    return rId; 
  } 
  public void setrId(Integer rId) { 
    this.rId = rId; 
  } 
  public String getFromUser() { 
    return fromUser; 
  } 
  public void setFromUser(String fromUser) { 
    this.fromUser = fromUser; 
  } 
  public String getToUser() { 
    return toUser; 
  } 
  public void setToUser(String toUser) { 
    this.toUser = toUser; 
  } 
  public String getContent() { 
    return content; 
  } 
  public void setContent(String content) { 
    this.content = content; 
  } 
  public String getrTime() { 
    return rTime; 
  } 
  public void setrTime(String rTime) { 
    this.rTime = rTime; 
  } 
  public Integer getIsReaded() { 
    return isReaded; 
  } 
  public void setIsReaded(Integer isReaded) { 
    this.isReaded = isReaded; 
  }
}

public Page getRecordPage(Page page, String loginName, 
      String contactName) { 
    int pageSize = page.getPageSize(); 
    int pageNo = page.getPageNo(); 
    String sql = "select * from " 
        + ContactsManagerDbAdapter.TABLENAME_RECORD 
        + " where (fromUser = ? and toUser = ?) or (fromUser = ? and toUser = ?)" 
        + " Limit " + String.valueOf(pageSize) + " Offset " 
        + String.valueOf(pageNo * pageSize); 
    String[] selectionArgs = { loginName, contactName, contactName, 
        loginName }; 
    Cursor cursor = mSQLiteDatabaseWritable.rawQuery(sql, selectionArgs); 
    List result = new ArrayList(); 
    for(cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext()){ 
      Record record = new Record(); 
      record.setrId(cursor.getInt(0)); 
      record.setFromUser(cursor.getString(1)); 
      record.setToUser(cursor.getString(2)); 
      record.setContent(cursor.getString(3)); 
      record.setrTime(cursor.getString(4)); 
      record.setIsReaded(cursor.getInt(5)); 
      result.add(record); 
    } 
    page.setTotalCount(getRowCount(loginName, contactName)); 
    page.setResult(result); 
    cursor.close(); 
    return page; 
} 
/** 
* 总记录数 
*/ 
public int getRowCount(String loginName, String contactName){ 
    String sql = "select * from " 
      + ContactsManagerDbAdapter.TABLENAME_RECORD 
      + " where (fromUser = ? and toUser = ?) or (fromUser = ? and toUser = ?)"; 
    String[] selectionArgs = { loginName, contactName, contactName,
        loginName }; 
    Cursor cursor = mSQLiteDatabaseWritable.rawQuery(sql, selectionArgs); 
    int count = cursor.getCount(); 
    cursor.close(); 
    return count; 
} 

public class ChatHistory extends Activity { 
  ListView historyView; 
  Button prevPageBtn; 
  Button nextPageBtn; 
  TextView historyPageTv; 
  Button backChatsHistoryBtn; 
  Button deleteHistoryBtn; 
  List historyRecordList;  
  Page page; 
  String loginName; 
  String contactName; 
  ChatHistoryService chatHistoryService; 
  ContactsManagerDbAdapter dbAdapter; 
  private BaseAdapter adapter; 
  private static final int STATUS_CHANGE = 0; 
  private Handler mHandler; 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    // TODO Auto-generated method stub 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.chats_history); 
    historyView = (ListView) findViewById(android.R.id.list); 
    prevPageBtn = (Button) findViewById(R.id.chat_prev_page); 
    nextPageBtn = (Button) findViewById(R.id.chat_next_page); 
    historyPageTv = (TextView) findViewById(R.id.history_page); 
    backChatsHistoryBtn = (Button) findViewById(R.id.back_chats_history); 
    deleteHistoryBtn = (Button) findViewById(R.id.delete_history); 
    SharedPreferences sharedata = ChatHistory.this.getSharedPreferences("data", 0); 
    loginName = sharedata.getString("loginName", ""); 
    contactName = getIntent().getStringExtra("contactName"); 
    dbAdapter = new ContactsManagerDbAdapter(getApplicationContext()); 
    dbAdapter.open(); 
    chatHistoryService = new ChatHistoryService(ChatHistory.this);
    page = new Page(); 
    page.setPageSize(8); 
    page = chatHistoryService.getHistoryPage(page, loginName, contactName, dbAdapter); 
    historyRecordList = page.getResult(); 
    updateTextView(); 
    prevPageBtn.setOnClickListener(prevPageButtonListener); 
    nextPageBtn.setOnClickListener(nextPageButtonListener); 
    backChatsHistoryBtn.setOnClickListener(backButtonListener); 
    deleteHistoryBtn.setOnClickListener(deleteHistoryButtonListener); 
    adapter = new HistoryListAdapter(ChatHistory.this); 
    historyView.setAdapter(adapter); 
    mHandler = new Handler(){  
       public void handleMessage(Message msg) { 
          switch(msg.what){ 
          case STATUS_CHANGE: 
            // 处理UI更新等操作 
            updateUI(); 
          } 
       }; 
    }; 
  } 
  private void updateUI() { 
    //详细的更新 
    adapter.notifyDataSetChanged();// 更新ListView 
    updateTextView(); 
  } 
  /** 
   * 更新页码 
   */ 
  private void updateTextView(){    
    if(historyRecordList.size() == 0){ 
      historyPageTv.setText(0 + "/" + 0); 
    } else{ 
      historyPageTv.setText(page.getPageNo() + 1 + "/" + page.getTotalPages()); 
    } 
  } 
  public class HistoryListAdapter extends BaseAdapter{ 
    private class RecentViewHolder { 
      TextView sender_context; 
      TextView rTime; 
    } 
    Context context; 
    LayoutInflater mInflater; 
    public HistoryListAdapter(Context context){ 
      this.context = context; 
      mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
    } 
    @Override 
    public int getCount() { 
      // TODO Auto-generated method stub 
      return historyRecordList.size(); 
    } 
    @Override 
    public Object getItem(int position) { 
      // TODO Auto-generated method stub 
      return historyRecordList.get(position); 
    } 
    @Override 
    public long getItemId(int position) { 
      // TODO Auto-generated method stub 
      return position; 
    } 
    @Override 
    public View getView(int position, View convertView, ViewGroup parent) { 
      // TODO Auto-generated method stub 
      RecentViewHolder holder; 
      if (convertView == null) { 
        convertView = mInflater.inflate(R.layout.message_layout, null); 
        holder = new RecentViewHolder(); 
        holder.sender_context = (TextView) convertView 
            .findViewById(R.id.message_view_sender_content);
        holder.rTime = (TextView) convertView 
            .findViewById(R.id.message_view_timestamp); 
        convertView.setTag(holder); 
      } else { 
        holder = (RecentViewHolder) convertView.getTag(); 
      } 
      Record record = historyRecordList.get(position); 
      if (record != null) { 
        holder.sender_context.setText(record.getFromUser() + ":" + record.getContent()); 
        holder.rTime.setText(record.getrTime()); 
      } 
      return convertView; 
    } 
  } 
  /** 
   * 上一页按钮的监听事件 
   */ 
  OnClickListener prevPageButtonListener = new OnClickListener(){ 
    @Override 
    public void onClick(View v) { 
      // TODO Auto-generated method stub 
      if(page.isHasPre()){ 
        page.setPageNo(page.getPageNo() - 1); 
        historyRecordList = chatHistoryService.getHistoryPage(page, loginName, contactName, dbAdapter).getResult(); 
        Message msg = new Message(); 
        msg.what = STATUS_CHANGE; 
        mHandler.sendMessage(msg);// 向Handler发送消息,更新UI 
      } 
    } 
  }; 
  /** 
   * 下一页按钮的监听事件 
   */ 
  OnClickListener nextPageButtonListener = new OnClickListener(){ 
    @Override 
    public void onClick(View v) { 
      // TODO Auto-generated method stub 
      if(page.isHasNext()){ 
        page.setPageNo(page.getPageNo() + 1); 
        historyRecordList = chatHistoryService.getHistoryPage(page, loginName, contactName, dbAdapter).getResult(); 
        Message msg = new Message(); 
        msg.what = STATUS_CHANGE; 
        mHandler.sendMessage(msg);// 向Handler发送消息,更新UI 
      } 
    } 
  }; 
  /** 
   * 删除历史记录按钮监听器 
   */ 
  OnClickListener deleteHistoryButtonListener = new OnClickListener() { 
    @Override 
    public void onClick(View v) { 
      // TODO Auto-generated method stub      
    } 
  }; 
  /** 退出聊天界面监听器 */ 
  OnClickListener backButtonListener = new OnClickListener() { 
    @Override 
    public void onClick(View v) { 
      // TODO Auto-generated method stub 
      // 返回到聊天界面 
      finish(); 
      dbAdapter.close(); 
    } 
  }; 
  @Override 
  public boolean onKeyDown(int keyCode, KeyEvent event) { 
    // 按下键盘上返回按钮 
    if (keyCode == KeyEvent.KEYCODE_BACK) { 
      finish(); 
      dbAdapter.close(); 
      return true; 
    } else { 
      return super.onKeyDown(keyCode, event); 
    }
  }
}

public class ChatHistoryService { 
  Context context; 
  public ChatHistoryService(Context context) { 
    this.context = context; 
  } 
  public Page getHistoryPage(Page page, String loginName, 
      String contactName, ContactsManagerDbAdapter dbAdapter) { 
    RecordDao recordDao = new RecordDao(dbAdapter); 
    return recordDao.getRecordPage(page, loginName, contactName); 
  } 
  public int deleteHistory(String loginName, 
      String contactName, ContactsManagerDbAdapter dbAdapter){ 
    RecordDao recordDao = new RecordDao(dbAdapter); 
    return recordDao.deleteHistoryRecord(loginName, contactName); 
  } 
}