Android--資料庫操作輔助類:SQLiteOpenHelper

來源:互聯網
上載者:User

Android--資料庫操作輔助類:SQLiteOpenHelper

1.MyDatabaseHelper.java代碼如下:

package org.lxh.demo;import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteDatabase.CursorFactory;import android.database.sqlite.SQLiteOpenHelper;public class MyDatabaseHelper extends SQLiteOpenHelper {private static final String DATABASENAME = "test.db";private static final int DATABASEVERSION = 1;private static final String TABLENAME = "mytab";public MyDatabaseHelper(Context context) {super(context, DATABASENAME, null, DATABASEVERSION);}@Overridepublic void onCreate(SQLiteDatabase db) {/* * String sql="CREATE TABLE"+TABLENAME+"("+ * "id    INTEGER    PRIMARY KEY,"+ "name   VARCHAR(50)  NOT NULL,"+ * "birthday   DATE   NOT NULL)"; */String sql = "CREATE TABLE " + TABLENAME+ "("+ "idINTEGERPRIMARY KEY ," // 在SQLite中設定為Integer、PRIMARY// KEY則ID自動成長+ "name VARCHAR(50) NOT NULL ," + "birthday DATE NOT NULL"+ ")";db.execSQL(sql); // 執行SQL}@Overridepublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {String sql = "DROP TABLE IF EXISTS" + TABLENAME;db.execSQL(sql);this.onCreate(db);}}
2.Hello.java代碼如下:

package org.lxh.demo;import android.app.Activity;import android.app.AlertDialog;import android.app.Dialog;import android.content.DialogInterface;import android.database.sqlite.SQLiteOpenHelper;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.view.View.OnFocusChangeListener;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;public class Hello extends Activity {public void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState); // 生命週期方法super.setContentView(R.layout.main); // 設定要使用的布局管理器SQLiteOpenHelper helper=new MyDatabaseHelper(this);helper.getWritableDatabase();}}

運行後如下:



聯繫我們

該頁面正文內容均來源於網絡整理,並不代表阿里雲官方的觀點,該頁面所提到的產品和服務也與阿里云無關,如果該頁面內容對您造成了困擾,歡迎寫郵件給我們,收到郵件我們將在5個工作日內處理。

如果您發現本社區中有涉嫌抄襲的內容,歡迎發送郵件至: info-contact@alibabacloud.com 進行舉報並提供相關證據,工作人員會在 5 個工作天內聯絡您,一經查實,本站將立刻刪除涉嫌侵權內容。

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.