Android提高第九篇之SQLite分页表格

 

本文来自http://blog.csdn.net/hellogv/ ，引用必须注明出处！

       上次讲的Android上的SQLite分页读取，只用文本框显示数据而已，这次就讲得更加深入些，实现并封装一个SQL分页表格控件，不仅支持分页还是以表格的形式展示数据。先来看看本文程序运行的动画：

       这个SQL分页表格控件主要分为“表格区”和“分页栏”这两部分，这两部分都是基于GridView实现的。网上介绍Android上实现表格的DEMO一般都用ListView。ListView与GridView对比，ListView最大的优势是格单元的大小可以自定义，可以某单元长某单元短，但是难于实现自适应数据表的结构；而GridView最大的优势就是自适应数据表的结构，但是格单元统一大小。。。对于数据表结构多变的情况，建议使用GridView实现表格。

本文实现的SQL分页表格控件有以下特点：

1.自适应数据表结构，但是格单元统一大小；

2.支持分页；

3.“表格区”有按键事件回调处理，“分页栏”有分页切换事件回调处理。

本文程序代码较多，可以到这里下载整个工程的源码：http://www.rayfile.com/files/72e78b68-f2e5-11df-8469-0015c55db73d/

items.xml的代码如下，它是“表格区”和“分页栏”的格单元实现：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout android:id="@+id/LinearLayout01"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent" android:background="#555555"
    android:layout_height="wrap_content">
    <TextView android:layout_below="@+id/ItemImage" android:text="TextView01"
        android:id="@+id/ItemText" android:bufferType="normal"
        android:singleLine="true" android:background="#000000"
        android:layout_width="fill_parent" android:gravity="center"
        android:layout_margin="1dip" android:layout_gravity="center"
        android:layout_height="wrap_content">
    </TextView>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?> <LinearLayout android:id="@+id/LinearLayout01" xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:background="#555555" android:layout_height="wrap_content"> <TextView android:layout_below="@+id/ItemImage" android:text="TextView01" android:id="@+id/ItemText" android:bufferType="normal" android:singleLine="true" android:background="#000000" android:layout_width="fill_parent" android:gravity="center" android:layout_margin="1dip" android:layout_gravity="center" android:layout_height="wrap_content"> </TextView> </LinearLayout>

main.xml的代码如下：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="fill_parent"
    android:layout_height="fill_parent" android:id="@+id/MainLinearLayout">
    <Button android:layout_height="wrap_content"
        android:layout_width="fill_parent" android:id="@+id/btnCreateDB"
        android:text="创建数据库"></Button>
    <Button android:layout_height="wrap_content"
        android:layout_width="fill_parent" android:text="插入一串实验数据" android:id="@+id/btnInsertRec"></Button>
    <Button android:layout_height="wrap_content" android:id="@+id/btnClose"
        android:text="关闭数据库" android:layout_width="fill_parent"></Button>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" android:id="@+id/MainLinearLayout"> <Button android:layout_height="wrap_content" android:layout_width="fill_parent" android:id="@+id/btnCreateDB" android:text="创建数据库"></Button> <Button android:layout_height="wrap_content" android:layout_width="fill_parent" android:text="插入一串实验数据" android:id="@+id/btnInsertRec"></Button> <Button android:layout_height="wrap_content" android:id="@+id/btnClose" android:text="关闭数据库" android:layout_width="fill_parent"></Button> </LinearLayout>

演示程序testSQLite.java的源码：

package com.testSQLite;
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.Button;
import android.widget.LinearLayout;
import android.widget.Toast;
public class testSQLite extends Activity {
    GVTable table;
    Button btnCreateDB, btnInsert, btnClose;
    SQLiteDatabase db;
    int id;//添加记录时的id累加标记，必须全局
    private static final String TABLE_NAME = "stu";
    private static final String ID = "id";
    private static final String NAME = "name";
    private static final String PHONE = "phone";
    private static final String ADDRESS = "address";
    private static final String AGE = "age";

    @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());
        table=new GVTable(this);
        table.gvSetTableRowCount(8);//设置每个分页的ROW总数
        LinearLayout ly = (LinearLayout) findViewById(R.id.MainLinearLayout);
        table.setTableOnClickListener(new GVTable.OnTableClickListener() {
            @Override
            public void onTableClickListener(int x,int y,Cursor c) {
                c.moveToPosition(y);
                String str=c.getString(x)+" 位置:("+String.valueOf(x)+","+String.valueOf(y)+")";
                Toast.makeText(testSQLite.this, str, 1000).show();
            }
        });
        table.setOnPageSwitchListener(new GVTable.OnPageSwitchListener() {

            @Override
            public void onPageSwitchListener(int pageID,int pageCount) {
                String str="共有"+String.valueOf(pageCount)+
                " 当前第"+String.valueOf(pageID)+"页";
                Toast.makeText(testSQLite.this, str, 1000).show();
            }
        });

        ly.addView(table);
    }
    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
                table.gvUpdatePageBar("select count(*) from " + TABLE_NAME,db);
                table.gvReadyTable("select * from " + TABLE_NAME,db);
            }else if (v == btnClose) {
                table.gvRemoveAll();
                db.close();

            }
        }
    }

    /**
     * 在内存创建数据库和数据表
     */
    void CreateDB() {
        // 在内存创建数据库
        db = SQLiteDatabase.create(null);
        Log.e("DB Path", db.getPath());
        String amount = String.valueOf(databaseList().length);
        Log.e("DB amount", amount);
        // 创建数据表
        String sql = "CREATE TABLE " + TABLE_NAME + " (" +
                ID  + " text not null, " + NAME + " text not null," +
                ADDRESS + " text not null, " + PHONE + " text not null," +
                AGE + " text not null "+");";
        try {
            db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
            db.execSQL(sql);
        } catch (SQLException e) {}
    }
    /**
     * 插入N条数据
     */
    void InsertRecord(int n) {
        int total = id + n;
        for (; id < total; id++) {
            String sql = "insert into " + TABLE_NAME + " (" +
            ID + ", " + NAME+", " + ADDRESS+", " + PHONE+", "+AGE
                    + ") values('" + String.valueOf(id) + "', 'man','address','123456789','18');";
            try {
                db.execSQL(sql);
            } catch (SQLException e) {
            }
        }
    }


}

package com.testSQLite; 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.Button; import android.widget.LinearLayout; import android.widget.Toast; public class testSQLite extends Activity { GVTable table; Button btnCreateDB, btnInsert, btnClose; SQLiteDatabase db; int id;//添加记录时的id累加标记，必须全局 private static final String TABLE_NAME = "stu"; private static final String ID = "id"; private static final String NAME = "name"; private static final String PHONE = "phone"; private static final String ADDRESS = "address"; private static final String AGE = "age"; @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()); table=new GVTable(this); table.gvSetTableRowCount(8);//设置每个分页的ROW总数 LinearLayout ly = (LinearLayout) findViewById(R.id.MainLinearLayout); table.setTableOnClickListener(new GVTable.OnTableClickListener() { @Override public void onTableClickListener(int x,int y,Cursor c) { c.moveToPosition(y); String str=c.getString(x)+" 位置:("+String.valueOf(x)+","+String.valueOf(y)+")"; Toast.makeText(testSQLite.this, str, 1000).show(); } }); table.setOnPageSwitchListener(new GVTable.OnPageSwitchListener() { @Override public void onPageSwitchListener(int pageID,int pageCount) { String str="共有"+String.valueOf(pageCount)+ " 当前第"+String.valueOf(pageID)+"页"; Toast.makeText(testSQLite.this, str, 1000).show(); } }); ly.addView(table); } 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 table.gvUpdatePageBar("select count(*) from " + TABLE_NAME,db); table.gvReadyTable("select * from " + TABLE_NAME,db); }else if (v == btnClose) { table.gvRemoveAll(); db.close(); } } } /** * 在内存创建数据库和数据表 */ void CreateDB() { // 在内存创建数据库 db = SQLiteDatabase.create(null); Log.e("DB Path", db.getPath()); String amount = String.valueOf(databaseList().length); Log.e("DB amount", amount); // 创建数据表 String sql = "CREATE TABLE " + TABLE_NAME + " (" + ID + " text not null, " + NAME + " text not null," + ADDRESS + " text not null, " + PHONE + " text not null," + AGE + " text not null "+");"; try { db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME); db.execSQL(sql); } catch (SQLException e) {} } /** * 插入N条数据 */ void InsertRecord(int n) { int total = id + n; for (; id < total; id++) { String sql = "insert into " + TABLE_NAME + " (" + ID + ", " + NAME+", " + ADDRESS+", " + PHONE+", "+AGE + ") values('" + String.valueOf(id) + "', 'man','address','123456789','18');"; try { db.execSQL(sql); } catch (SQLException e) { } } } }

分页表格控件GVTable.java的源码：

package com.testSQLite;
import java.util.ArrayList;
import java.util.HashMap;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.LinearLayout;
import android.widget.SimpleAdapter;
import android.widget.AdapterView.OnItemClickListener;
public class GVTable extends LinearLayout {
    protected GridView gvTable,gvPage;
    protected SimpleAdapter saPageID,saTable;// 适配器
    protected ArrayList<HashMap<String, String>> srcPageID,srcTable;// 数据源

    protected int TableRowCount=10;//分页时，每页的Row总数
    protected int TableColCount=0;//每页col的数量
    protected SQLiteDatabase db;
    protected String rawSQL="";
    protected Cursor curTable;//分页时使用的Cursor
    protected OnTableClickListener clickListener;//整个分页控件被点击时的回调函数
    protected OnPageSwitchListener switchListener;//分页切换时的回调函数

    public GVTable(Context context) {
        super(context);
        this.setOrientation(VERTICAL);//垂直
        //----------------------------------------
        gvTable=new GridView(context);
        addView(gvTable, new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT,
                LayoutParams.WRAP_CONTENT));//宽长式样

        srcTable = new ArrayList<HashMap<String, String>>();
        saTable = new SimpleAdapter(context,
                srcTable,// 数据来源
                R.layout.items,//XML实现
                new String[] { "ItemText" },// 动态数组与ImageItem对应的子项
                new int[] { R.id.ItemText });
        // 添加并且显示
        gvTable.setAdapter(saTable);
        gvTable.setOnItemClickListener(new OnItemClickListener(){
            @Override
            public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                    long arg3) {
                int y=arg2/curTable.getColumnCount()-1;//标题栏的不算
                int x=arg2 % curTable.getColumnCount();
                if (clickListener != null//分页数据被点击
                        && y!=-1) {//点中的不是标题栏时
                    clickListener.onTableClickListener(x,y,curTable);
                }
            }
        });

        //----------------------------------------
        gvPage=new GridView(context);
        gvPage.setColumnWidth(40);//设置每个分页按钮的宽度
        gvPage.setNumColumns(GridView.AUTO_FIT);//分页按钮数量自动设置
        addView(gvPage, new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT,
                LayoutParams.WRAP_CONTENT));//宽长式样
        srcPageID = new ArrayList<HashMap<String, String>>();
        saPageID = new SimpleAdapter(context,
                srcPageID,// 数据来源
                R.layout.items,//XML实现
                new String[] { "ItemText" },// 动态数组与ImageItem对应的子项
                new int[] { R.id.ItemText });
        // 添加并且显示
        gvPage.setAdapter(saPageID);
        // 添加消息处理
        gvPage.setOnItemClickListener(new OnItemClickListener(){
            @Override
            public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                    long arg3) {
                LoadTable(arg2);//根据所选分页读取对应的数据
                if(switchListener!=null){//分页切换时
                    switchListener.onPageSwitchListener(arg2,srcPageID.size());
                }
            }
        });
    }
    /**
     * 清除所有数据
     */
    public void gvRemoveAll()
    {
        if(this.curTable!=null)
            curTable.close();
        srcTable.clear();
        saTable.notifyDataSetChanged();

        srcPageID.clear();
        saPageID.notifyDataSetChanged();

    }
    /**
     * 读取指定ID的分页数据,返回当前页的总数据
     * 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
     * @param pageID 指定的分页ID
     */
    protected void LoadTable(int pageID)
    {
        if(curTable!=null)//释放上次的数据
            curTable.close();

        String sql= rawSQL+" Limit "+String.valueOf(TableRowCount)+ " Offset " +String.valueOf(pageID*TableRowCount);
        curTable = db.rawQuery(sql, null);

        gvTable.setNumColumns(curTable.getColumnCount());//表现为表格的关键点！
        TableColCount=curTable.getColumnCount();
        srcTable.clear();
        // 取得字段名称
        int colCount = curTable.getColumnCount();
        for (int i = 0; i < colCount; i++) {
            HashMap<String, String> map = new HashMap<String, String>();
            map.put("ItemText", curTable.getColumnName(i));
            srcTable.add(map);
        }

        // 列举出所有数据
        int recCount=curTable.getCount();
        for (int i = 0; i < recCount; i++) {//定位到一条数据
            curTable.moveToPosition(i);
            for(int ii=0;ii<colCount;ii++)//定位到一条数据中的每个字段
            {
                HashMap<String, String> map = new HashMap<String, String>();
                map.put("ItemText", curTable.getString(ii));
                srcTable.add(map);
            }
        }

        saTable.notifyDataSetChanged();
    }
    /**
     * 设置表格的最多显示的行数
     * @param row 表格的行数
     */
    public void gvSetTableRowCount(int row)
    {
        TableRowCount=row;
    }

    /**
     * 取得表格的最大行数
     * @return 行数
     */
    public int gvGetTableRowCount()
    {
        return TableRowCount;
    }

    /**
     * 取得当前分页的Cursor
     * @return 当前分页的Cursor
     */
    public Cursor gvGetCurrentTable()
    {
        return curTable;
    }

    /**
     * 准备分页显示数据
     * @param rawSQL sql语句
     * @param db 数据库
     */
    public void gvReadyTable(String rawSQL,SQLiteDatabase db)
    {
        this.rawSQL=rawSQL;
        this.db=db;
    }

    /**
     * 刷新分页栏，更新按钮数量
     * @param sql SQL语句
     * @param db 数据库
     */
    public void gvUpdatePageBar(String sql,SQLiteDatabase db)
    {
        Cursor rec = db.rawQuery(sql, null);
        rec.moveToLast();
        long recSize=rec.getLong(0);//取得总数
        rec.close();
        int pageNum=(int)(recSize/TableRowCount) + 1;//取得分页数

        srcPageID.clear();
        for (int i = 0; i < pageNum; i++) {
            HashMap<String, String> map = new HashMap<String, String>();
            map.put("ItemText", "No." + String.valueOf(i));// 添加图像资源的ID
            srcPageID.add(map);
        }
        saPageID.notifyDataSetChanged();
    }
    //---------------------------------------------------------
    /**
     * 表格被点击时的回调函数
     */
    public void setTableOnClickListener(OnTableClickListener click) {
        this.clickListener = click;
    }

    public interface OnTableClickListener {
        public void onTableClickListener(int x,int y,Cursor c);
    }
    //---------------------------------------------------------
    /**
     * 分页栏被点击时的回调函数
     */
    public void setOnPageSwitchListener(OnPageSwitchListener pageSwitch) {
        this.switchListener = pageSwitch;
    }
    public interface OnPageSwitchListener {
        public void onPageSwitchListener(int pageID,int pageCount);
    }
}