21天学习android开发教程之SQLite分页读取

<&＃63;xml version="1.0" encoding="utf-8"&＃63;>

    
    
 

<&＃63;xml version="1.0" encoding="utf-8"&＃63;>

    
    
    
    
    

package com.testSQLite; 
 
import java.util.ArrayList; 
import java.util.HashMap; 
import android.app.Activity; 
import android.database.Cursor; 
import android.database.SQLException; 
import android.database.sqlite.SQLiteDatabase; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.View; 
import android.widget.AdapterView; 
import android.widget.AdapterView.OnItemClickListener; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.GridView; 
import android.widget.SimpleAdapter; 
 
public class testSQLite extends Activity { 
  /** Called when the activity is first created. */ 
  Button btnCreateDB, btnInsert, btnClose; 
  EditText edtSQL;//显示分页数据 
  SQLiteDatabase db; 
  int id;//添加记录时的id累加标记，必须全局 
  static final int PageSize=10;//分页时，每页的数据总数 
  private static final String TABLE_NAME = "stu"; 
  private static final String ID = "id"; 
  private static final String NAME = "name"; 
   
  SimpleAdapter saPageID;// 分页栏适配器 
  ArrayList> lstPageID;// 分页栏的数据源，与PageSize和数据总数相关 
 
  @Override 
  public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 
    btnCreateDB = (Button) this.findViewById(R.id.btnCreateDB); 
    btnCreateDB.setOnClickListener(new ClickEvent()); 
 
    btnInsert = (Button) this.findViewById(R.id.btnInsertRec); 
    btnInsert.setOnClickListener(new ClickEvent()); 
 
    btnClose = (Button) this.findViewById(R.id.btnClose); 
    btnClose.setOnClickListener(new ClickEvent()); 
     
    edtSQL=(EditText)this.findViewById(R.id.EditText01); 
     
    GridView gridview = (GridView) findViewById(R.id.gridview);//分页栏控件 
    // 生成动态数组，并且转入数据 
    lstPageID = new ArrayList>(); 
 
    // 生成适配器的ImageItem <====> 动态数组的元素，两者一一对应 
    saPageID = new SimpleAdapter(testSQLite.this, // 没什么解释 
        lstPageID,// 数据来源 
        R.layout.pagebuttons,//XML实现 
        new String[] { "ItemText" }, 
        new int[] { R.id.ItemText }); 
 
    // 添加并且显示 
    gridview.setAdapter(saPageID); 
    // 添加消息处理 
    gridview.setOnItemClickListener(new OnItemClickListener(){ 
 
      @Override 
      public void onItemClick(AdapterView<&＃63;> arg0, View arg1, int arg2, 
          long arg3) { 
        LoadPage(arg2);//根据所选分页读取对应的数据 
      } 
    }); 
 
  } 
 
   
  class ClickEvent implements View.OnClickListener { 
 
    @Override 
    public void onClick(View v) { 
      if (v == btnCreateDB) { 
        CreateDB(); 
      } else if (v == btnInsert) { 
        InsertRecord(16);//插入16条记录 
        RefreshPage(); 
      }else if (v == btnClose) { 
        db.close(); 
      } 
    } 
 
  } 
   
 
  /* 
   * 读取指定ID的分页数据 
   * SQL:Select * From TABLE_NAME Limit 9 Offset 10; 
   * 表示从TABLE_NAME表获取数据，跳过10行，取9行 
   */ 
  void LoadPage(int pageID) 
  { 
    String sql= "select * from " + TABLE_NAME +  
    " Limit "+String.valueOf(PageSize)+ " Offset " +String.valueOf(pageID*PageSize); 
    Cursor rec = db.rawQuery(sql, null); 
 
    setTitle("当前分页的数据总数:"+String.valueOf(rec.getCount())); 
     
    // 取得字段名称 
    String title = ""; 
    int colCount = rec.getColumnCount(); 
    for (int i = 0; i  map = new HashMap(); 
      map.put("ItemText", "No." + String.valueOf(i));
 
      lstPageID.add(map); 
    } 
    saPageID.notifyDataSetChanged(); 
  } 
}