android SQLite数据库基本操作示例

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;private final static String DATABASE_NAME = "SQLite.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;@Overridepublic 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Cursortry {/* 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CursorCursor 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,// 数据库的Cursor对象new String[] { TABLE_NUM, TABLE_DATA },// 与NAME和NUMBER对应的Viewsnew 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) {/* 关闭数据库（易忘） */mSQLiteDatabase.close();this.finish();return true;}return super.onKeyDown(keyCode, event);}}
上面的测试数据8是之前创建的。。
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