这个例子实现了一个完整的数据库操作示例。首先运行项目，初始化数据库(创建数据库、创建表)；然后点击左方向键向表中插入一条数据，按右方向键删除一条数据，按数字键1修改表中指定的一条数据，数字键2可以删除一个表，数字键1 删除数据库。代码如下：
package eoe.android.Demo; import android.app.Activity; import android.content.ContentValues; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.graphics.Color; import android.os.Bundle; import android.view.KeyEvent; import android.widget.LinearLayout; import android.widget.ListAdapter; import android.widget.ListView; import android.widget.SimpleCursorAdapter; public class Activity01 extends Activity { private static int miCount = 0; /* 数据库对象 */ private SQLiteDatabase mSQLiteDatabase = null; /* 数据库名 */ private final static String DATABASE_NAME = "demo.db"; /* 表名 */ private final static String TABLE_NAME = "table1"; /* 表中的字段 */ private final static String TABLE_ID = "_id"; private final static String TABLE_NUM = "num"; private final static String TABLE_DATA = "data"; /* 创建表的sql语句 */ private final static String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME + " (" + TABLE_ID + " INTEGER PRIMARY KEY," + TABLE_NUM + " INTERGER,"+ TABLE_DATA + " TEXT)"; /* 线性布局 */ LinearLayout m_LinearLayout = null; /* 列表视图-显示数据库中的数据 */ ListView m_ListView = null; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); /* 创建LinearLayout布局对象 */ m_LinearLayout = new LinearLayout( this); /* 设置布局LinearLayout的属性 */ m_LinearLayout.setOrientation(LinearLayout.VERTICAL); m_LinearLayout.setBackgroundColor(android.graphics.Color.BLACK); /* 创建ListView对象 */ m_ListView = new ListView( this); LinearLayout.LayoutParams param = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT); m_ListView.setBackgroundColor(Color.BLACK); /* 添加m_ListView到m_LinearLayout布局 */ m_LinearLayout.addView(m_ListView, param); /* 设置显示m_LinearLayout布局 */ setContentView(m_LinearLayout); // 打开已经存在的数据库 mSQLiteDatabase = this.openOrCreateDatabase(DATABASE_NAME, MODE_PRIVATE, null); // 获取数据库Phones的Cursor try { /* 在数据库mSQLiteDatabase中创建一个表 */ mSQLiteDatabase.execSQL(CREATE_TABLE); } catch (Exception e) { UpdataAdapter(); } } public boolean onKeyUp( int keyCode, KeyEvent event) { switch (keyCode) { case KeyEvent.KEYCODE_DPAD_LEFT: AddData(); break; case KeyEvent.KEYCODE_DPAD_RIGHT: DeleteData(); break; case KeyEvent.KEYCODE_1: UpData(); break; case KeyEvent.KEYCODE_2: DeleteTable(); break; case KeyEvent.KEYCODE_3: DeleteDataBase(); break; } return true; } /* 删除数据库 */ public void DeleteDataBase() { this.deleteDatabase(DATABASE_NAME); this.finish(); } /* 删除一个表 */ public void DeleteTable() { mSQLiteDatabase.execSQL( "DROP TABLE " + TABLE_NAME); this.finish(); } /* 更新一条数据 */ public void UpData() { ContentValues cv = new ContentValues(); cv.put(TABLE_NUM, miCount); cv.put(TABLE_DATA, "修改后的数据" + miCount); /* 更新数据 */ mSQLiteDatabase.update(TABLE_NAME, cv, TABLE_NUM + "=" + Integer.toString(miCount - 1), null); UpdataAdapter(); } /* 向表中添加一条数据 */ public void AddData() { ContentValues cv = new ContentValues(); cv.put(TABLE_NUM, miCount); cv.put(TABLE_DATA, "测试数据库数据" + miCount); /* 插入数据 */ mSQLiteDatabase.insert(TABLE_NAME, null, cv); miCount++; UpdataAdapter(); } /* 从表中删除指定的一条数据 */ public void DeleteData() { /* 删除数据 */ mSQLiteDatabase.execSQL( "DELETE FROM " + TABLE_NAME + " WHERE _id=" + Integer.toString(miCount)); miCount--; if (miCount < 0) { miCount = 0; } UpdataAdapter(); } /* 更行试图显示 */ public void UpdataAdapter() { // 获取数据库Phones的Cursor Cursor cur = mSQLiteDatabase.query(TABLE_NAME, new String[] { TABLE_ID, TABLE_NUM, TABLE_DATA }, null, null, null, null, null); miCount = cur.getCount(); if (cur != null && cur.getCount() >= 0) { // ListAdapter是ListView和后台数据的桥梁 ListAdapter adapter = new SimpleCursorAdapter( this, // 定义List中每一行的显示模板 // 表示每一行包含两个数据项 android.R.layout.simple_list_item_2, // 数据库的Cursor对象 cur, // 从数据库的TABLE_NUM和TABLE_DATA两列中取数据 new String[] { TABLE_NUM, TABLE_DATA }, // 与NAME和NUMBER对应的Views new int[] { android.R.id.text1, android.R.id.text2 }); /* 将adapter添加到m_ListView中 */ m_ListView.setAdapter(adapter); } } /* 按键事件处理 */ public boolean onKeyDown( int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_BACK) { /* 退出时，不要忘记关闭 */ mSQLiteDatabase.close(); this.finish(); return true; } return super.onKeyDown(keyCode, event); } }