Android SQLiteOpenHelper的使用

package com.Aina.Android;import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;import android.database.sqlite.SQLiteDatabase.CursorFactory;/** * com.Aina.Android Pro_SQLiteDatabase *  * @author Aina.huang E-mail: 674023920@qq.com * @version 创建时间：2010 Jun 29, 2010 9:57:21 AM 类说明 */public class DatabaseHelper extends SQLiteOpenHelper {private Context mContext = null;private String str = "";private String table = "";public DatabaseHelper(Context context, String name, CursorFactory factory,int version, String str, String table) {super(context, name, factory, version);this.mContext = context;this.str = str;this.table = table;}@Overridepublic void onCreate(SQLiteDatabase db) {// TODO Auto-generated method stubdb.execSQL(str);}@Overridepublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {db.execSQL("DROP TABLE "+table);this.onCreate(db);}}

package com.Aina.Android;import android.content.ContentValues;import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;/** * com.Aina.Android Pro_SQLiteDatabase *  * @author Aina.huang E-mail: 674023920@qq.com * @version 创建时间：2010 Jun 29, 2010 10:11:57 AM 类说明 */public class MyDataBaseAdapter {private Context mContext = null;private SQLiteDatabase mSQLiteDatabase = null;private DatabaseHelper dh = null;private static final String DB_NAME = "Text.db";private static final int DB_VERSION = 1;private static final String TABLE_NAME = "table1";private static final String COLUMN_ID = "_id";public static final String COLUMN_NAME = "name";public static final String COLUMN_DATA = "data";private static final String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME+ " (" + COLUMN_ID + " INTEGER PRIMARY KEY," + COLUMN_NAME+ " TEXT," + COLUMN_DATA + " INTEGER NOT NULL)";public MyDataBaseAdapter(Context context){mContext = context;}/** * 打开数据库 */public void open(){dh = new DatabaseHelper(mContext,DB_NAME,null,DB_VERSION,CREATE_TABLE,TABLE_NAME);mSQLiteDatabase = dh.getWritableDatabase();}/** * 关闭数据库 */public void close(){dh.close();}/** * 插入 */public void insert(){try{ContentValues cv = new ContentValues();cv.put(COLUMN_NAME, "张三");cv.put(COLUMN_DATA, 10);mSQLiteDatabase.insert(TABLE_NAME, null, cv);}catch(Exception ex){ex.printStackTrace();}}/** * 修改 */public void update(){try{String sql = "UPDATE "+TABLE_NAME+" SET "+COLUMN_NAME+" ='李四' WHERE  _id=1";mSQLiteDatabase.execSQL(sql);}catch(Exception ex){ex.printStackTrace();}}/** * 修改 */public void delete(){try{mSQLiteDatabase.delete(TABLE_NAME, "_id=2", null);}catch(Exception ex){ex.printStackTrace();}}/** * 查询 */public Cursor select(){Cursor cursor = null;try{String sql = "SELECT * FROM "+TABLE_NAME;cursor = mSQLiteDatabase.rawQuery(sql, null);return cursor;}catch(Exception ex){ex.printStackTrace();return null;}}}

package com.Aina.Android;import android.app.Activity;import android.database.Cursor;import android.graphics.Color;import android.os.Bundle;import android.view.KeyEvent;import android.widget.LinearLayout;import android.widget.ListAdapter;import android.widget.SimpleCursorAdapter;import android.widget.LinearLayout.LayoutParams;import android.widget.ListView;public class Test extends Activity {/** Called when the activity is first created. */private MyDataBaseAdapter mdba = null;private LinearLayout ll = null;private ListView lv = null;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);ll = new LinearLayout(this);ll.setOrientation(LinearLayout.VERTICAL);ll.setBackgroundColor(Color.BLACK);ll.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));lv = new ListView(this);lv.setBackgroundColor(Color.BLACK);ll.addView(lv, new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));setContentView(ll);mdba = new MyDataBaseAdapter(this);mdba.open();this.show();}@Overrideprotected void onPause() {super.onPause();mdba.close();}@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {switch (keyCode) {case KeyEvent.KEYCODE_DPAD_LEFT:mdba.insert();break;case KeyEvent.KEYCODE_DPAD_RIGHT:mdba.delete();break;case KeyEvent.KEYCODE_DPAD_UP:mdba.update();break;}this.show();return super.onKeyDown(keyCode, event);}private void show() {Cursor cursor = mdba.select();if (cursor != null) {ListAdapter adapter = new SimpleCursorAdapter(this,android.R.layout.simple_list_item_2, cursor, new String[] {MyDataBaseAdapter.COLUMN_NAME,MyDataBaseAdapter.COLUMN_DATA }, new int[] {android.R.id.text1, android.R.id.text2 });lv.setAdapter(adapter);}}}

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