ListView分页（一）

Android ListView 实现分页数据显示

1、MiaiActivity 类：主要的Activity类

public class MianActivity extends Activity implements OnScrollListener {

 private ListView listView = null;
 private int currentPage = 1;
 private int lineSize = 25;// 每页显示
 private int pageSize = 1;// 总页数
 private int lastitem = 0;
 private int allrecorders = 0;// 总记录数
 private SimpleAdapter adapter = null;
 private List<Map<String, Object>> listdata = null;
 // 定义在下方显示 信息
 private LinearLayout bottomLayout = null;
 private TextView loadInfo = null;
 //
 private android.widget.LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
   LinearLayout.LayoutParams.FILL_PARENT,
   LinearLayout.LayoutParams.WRAP_CONTENT);

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_mian);
  // 初始化
  initWidget();
  // 加载显示数据
  showAlldata();
  // 计算总页数
  this.pageSize = (this.allrecorders % lineSize == 0) ? this.allrecorders
    / lineSize : this.allrecorders / lineSize + 1;

 }

 public void initWidget() {
  bottomLayout = new LinearLayout(this);
  this.loadInfo = new TextView(this);
  this.loadInfo.setText("加载中ING....");
  this.loadInfo.setGravity(Gravity.CENTER);
  this.loadInfo.setTextColor(Color.BLACK);
  this.loadInfo.setTextSize(30);
  bottomLayout.addView(loadInfo, layoutParams);

 }

 @Override
 public boolean onCreateOptionsMenu(Menu menu) {
  // Inflate the menu; this adds items to the action bar if it is present.
  getMenuInflater().inflate(R.menu.mian, menu);
  return true;
 }

 // 显示ListView数据
 public void showAlldata() {
  listView = (ListView) findViewById(R.id.listView1);
  ListQueryDAO queryDao = new ListQueryDAO(this);
  // 求出总记录数
  allrecorders = queryDao.getCountRow();
  listdata = queryDao.findData(currentPage, lineSize);
  this.adapter = new SimpleAdapter(this, listdata,
    R.layout.list_view_layout, DBHelper.LinkanColumns.COLUMNS,
    new int[] { R.id.myviewId, R.id.myviewName, R.id.myviewPhone });
  listView.addFooterView(bottomLayout);
  listView.setAdapter(this.adapter);
  listView.setOnScrollListener(this);
 }

 public void appendData() {
  ListQueryDAO queryDao = new ListQueryDAO(this);
  List<Map<String, Object>> newdata = queryDao.findData(this.currentPage,
    lineSize);
  listdata.addAll(newdata);
  this.adapter.notifyDataSetChanged();

 }

 // 监听来自屏幕滚动
 @Override
 public void onScroll(AbsListView listview, int firstVisiableitem,
   int visiableItemCount, int tatalItemCount) {
  // TODO Auto-generated method stub
  this.lastitem = firstVisiableitem + visiableItemCount - 1;
 }

 @Override
 public void onScrollStateChanged(AbsListView arg0, int scrollstatus) {
  // TODO Auto-generated method stub
  if (this.lastitem == this.adapter.getCount()
    && this.currentPage < this.pageSize
    && scrollstatus == OnScrollListener.SCROLL_STATE_IDLE) {
   this.currentPage++;
   this.listView.setSelection(this.lastitem);
   this.appendData();
  }

 }

}

2、SQLite数据库封装类

  DBHelper.java类

package com.tsinghua.datasource;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class DBHelper {
 private Context context;
 private SQLiteDatabase dbInstance;
 private DBCreator dbCreator;
 private String tableName="myAddressBook";

 public static final int DB_VERSION = 1;

 public static final String DB_NAME = "db_addressbook.db";

 public static final String TABLE_NAME_LINKMAN = "myAddressBook";

 public DBHelper(Context context) {
  this.context = context;
 }

 public static final String CREATE_TABLE = new StringBuffer()
   .append("Create table ").append(TABLE_NAME_LINKMAN).append(" (")
   .append(LinkanColumns.COLUMN_ID).append(" integer primary key,")
   .append(LinkanColumns.COLUMN_NAME).append(" text not null,")  
   .append(LinkanColumns.COLUMN_PHONE).append(" text )")
   .toString();

 public static final String QUERY_LINKMAN_TABLE = new StringBuilder()
   .append("select * from ").append(TABLE_NAME_LINKMAN)
   .toString();

 public static final class LinkanColumns {
  public static final String COLUMN_ID = "_id";//
  public static final String COLUMN_NAME = "name";
  public static final String COLUMN_PHONE = "phoneName";

  public static final String[] COLUMNS = { COLUMN_ID, COLUMN_NAME,
    COLUMN_PHONE };
 }
 //打开
 public void open() {
  dbCreator = new DBCreator(context, DBHelper.DB_NAME, null,
    DBHelper.DB_VERSION, DBHelper.CREATE_TABLE, tableName);
  dbInstance = dbCreator.getWritableDatabase();
 }

 public void close() {
  dbCreator.close();
 }

 public long insert(ContentValues values) {
  return dbInstance.insert(tableName, null, values);
 }

 public int update(ContentValues values, String whereClause,
   String[] whereArgs) {
  return dbInstance.update(tableName, values, whereClause, whereArgs);
 }

 public int delete(String whereClause, String[] whereArgs) {
  return dbInstance.delete(tableName, whereClause, whereArgs);
 }

 public Cursor query(String sql, String[] selectionArgs) {
  return dbInstance.rawQuery(sql, selectionArgs);
 }

 public Cursor query() {
  return dbInstance.query(tableName, null, null, null, null, null,
    DBHelper.LinkanColumns.COLUMN_NAME);
 }

 public void setTableName(String tableName) {
  this.tableName = tableName;
 }

 
 // database Operation 类
 private class DBCreator extends SQLiteOpenHelper {
  private Context context;
  private String createTableSql;
  private String tableName;

  public DBCreator(Context context, String name, CursorFactory factory,
    int version, String createTableSql, String tableName) {
   super(context, name, factory, version);
   this.context = context;
   this.createTableSql = createTableSql;
  // this.tableName = tableName;
  }

  @Override
  public void onCreate(SQLiteDatabase db) {
   db.execSQL(createTableSql);
  }

  @Override
  public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
   db.execSQL("drop table if exists " + tableName);
   onCreate(db);
  }
 }
}

 

  Dao封装类，ListQueryDAO .java 继承自DBHelper类 

 

/**
 *
 * @author Administrator 分页查询
 *
 */
public class ListQueryDAO extends DBHelper {

 public ListQueryDAO(Context context) {
  super(context);
  // TODO Auto-generated constructor stub
 }

 public long addInfo(Integer id, String _name, String phone) {
  open();
  ContentValues values = new ContentValues();
  values.put(DBHelper.LinkanColumns.COLUMN_ID, id);
  values.put(DBHelper.LinkanColumns.COLUMN_NAME, _name);
  values.put(DBHelper.LinkanColumns.COLUMN_PHONE, phone);
  long id_ = insert(values);
  close();
  return id_;
 }

 public Cursor querInfo() {
  open();
  Cursor cursor = query();
  return cursor;
 }

 /**
  * 查询多少条
  *
  * @return
  */
 public int getCountRow() {
  open();
  int count = 0;
  final String sql = new StringBuffer().append(
    "select count(_id) from " + DBHelper.TABLE_NAME_LINKMAN + "")
    .toString();
  
  Cursor row_cursor = query(sql, null);
  for (row_cursor.moveToFirst(); !row_cursor.isAfterLast(); row_cursor
    .moveToNext()) {
   count = row_cursor.getInt(0);

  }
  close();
  return count;
 }

 public List<Map<String, Object>> findData(int current, int lineSize) {
  List<Map<String, Object>> all = new ArrayList<Map<String, Object>>();
  final String sql = new StringBuffer().append("SELECT  ")
    .append(DBHelper.LinkanColumns.COLUMN_ID).append(" ,")
    .append(DBHelper.LinkanColumns.COLUMN_NAME).append(" ,")
    .append(DBHelper.LinkanColumns.COLUMN_PHONE).append(" ")
    .append(" FROM ").append(DBHelper.TABLE_NAME_LINKMAN).append(" LIMIT ?,?")
    .toString();

  System.out.println(sql);
  String selectArgs[] = new String[] {
    String.valueOf((current - 1) * lineSize),
    String.valueOf(lineSize) };
  open();
  Cursor result = query(sql, selectArgs);  
  for (result.moveToFirst(); !result.isAfterLast(); result.moveToNext()) {
   Map<String, Object> maps = new HashMap<String, Object>();
   maps.put(DBHelper.LinkanColumns.COLUMN_ID, result.getInt(0));
   maps.put(DBHelper.LinkanColumns.COLUMN_NAME, result.getString(1));
   maps.put(DBHelper.LinkanColumns.COLUMN_PHONE, result.getString(2));
   all.add(maps);
  }
  return all;
 }

}

二、布局类 activity_mian.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/mylayout"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    tools:context=".MianActivity" >
    <ListView
        android:id="@+id/listView1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" >
    </ListView>

</LinearLayout>

 

Liew的布局文件   list_view_layout.xml

 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal" >

    <TextView
        android:id="@+id/myviewId"
        android:layout_width="100px"
        android:gravity="center_horizontal"
        android:layout_height="wrap_content"
        android:textSize="30px"
            
         />

    <TextView
        android:id="@+id/myviewName"
        android:layout_width="180px"
        android:gravity="center_horizontal"
        android:layout_height="wrap_content"     
        android:textSize="30px"
        />

    <TextView
        android:id="@+id/myviewPhone"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
   
        android:textSize="30px"
        />

</LinearLayout>