import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {

    private Button create_database = null;
    private Button update_database = null;
    private Button insert = null;
    private Button update = null;
    private Button query = null;
    private Button delete = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        create_database = (Button)findViewById(R.id.create_database);
        create_database.setOnClickListener(new CreateDatabaseOnClickListener());
        update_database = (Button)findViewById(R.id.update_database);
        update_database.setOnClickListener(new UpdateDatabaseOnClickListener());
        insert = (Button)findViewById(R.id.insert);
        insert.setOnClickListener(new InsertOnClickListener());
        update = (Button)findViewById(R.id.update);
        update.setOnClickListener(new UpdateOnClickListener());
        query = (Button)findViewById(R.id.query);
        query.setOnClickListener(new QueryOnClickListener());
        delete = (Button)findViewById(R.id.delete);
        delete.setOnClickListener(new DeleteOnClickListener());
    }

    public class CreateDatabaseOnClickListener implements OnClickListener{

        public void onClick(View v) {
            // TODO Auto-generated method stub
            //創(chuàng)建一個DatabaseHelper類的對象，該類是單獨一個java文件,這里采用2個參數(shù)的構(gòu)造函數(shù)，建立的數(shù)據(jù)
            //庫的名字為tornadomeet.db
            DatabaseHelper database_helper = new DatabaseHelper(MainActivity.this, "tornadomeet.db");
            //只有調(diào)用getReadableDatabase()或者getWriteableDatabase()函數(shù)后才能返回一個SQLiteDatabase對象
            SQLiteDatabase db = database_helper.getReadableDatabase();
        }               
    }

    public class UpdateDatabaseOnClickListener implements OnClickListener{

        public void onClick(View v) {
            // TODO Auto-generated method stub
            DatabaseHelper database_helper = new DatabaseHelper(MainActivity.this, "tornadomeet.db", 2);
            SQLiteDatabase db = database_helper.getReadableDatabase();
        }       
    }

    public class InsertOnClickListener implements OnClickListener{

        public void onClick(View v) {
            // 生成contentvallues對象，該對象用來存數(shù)據(jù)的
            ContentValues values = new ContentValues();
            values.put("id", 1);//注意值的類型要匹配
            values.put("name", "tornado");
            DatabaseHelper database_helper = new DatabaseHelper(MainActivity.this, "tornadomeet.db");
            SQLiteDatabase db = database_helper.getWritableDatabase();//這里是獲得可寫的數(shù)據(jù)庫
            db.insert("user1", null, values);
        }      
    }

    public class UpdateOnClickListener implements OnClickListener{

        public void onClick(View v) {
            // TODO Auto-generated method stub
            DatabaseHelper database_helper = new DatabaseHelper(MainActivity.this, "tornadomeet.db");
            SQLiteDatabase db = database_helper.getWritableDatabase();
            ContentValues values = new ContentValues();
            values.put("name", "tornadomeet");
            //參數(shù)1為表名，參數(shù)2為更新后的值，參數(shù)3表示滿足條件的列名稱，參數(shù)4為該列名下的值
            db.update("user1", values, "id=?", new String[]{"1"});
        }       
    }

    public class QueryOnClickListener implements OnClickListener{

        public void onClick(View v) {
            // TODO Auto-generated method stub
            DatabaseHelper database_helper = new DatabaseHelper(MainActivity.this, "tornadomeet.db");
            SQLiteDatabase db = database_helper.getWritableDatabase();
            //查詢的語法，參數(shù)1為表名；參數(shù)2為表中的列名；參數(shù)3為要查詢的列名；參數(shù)時為對應(yīng)列的值；該函數(shù)返回的是一個游標
            Cursor cursor = db.query("user1", new String[]{"id", "name"}, "id=?", new String[]{"1"},  null, null, null);
            //遍歷每一個記錄
            while(cursor.moveToNext()) {
                String name = cursor.getString(cursor.getColumnIndex("name"));//返回列名為name的值
                System.out.println("query---->" + name);
            }
        }      
    }

    public class DeleteOnClickListener implements OnClickListener{

        public void onClick(View v) {
            // TODO Auto-generated method stub
            DatabaseHelper database_helper = new DatabaseHelper(MainActivity.this, "tornadomeet.db");
            SQLiteDatabase db = database_helper.getWritableDatabase();
            //直接刪除名為tornadomeet對應(yīng)的那條記錄
            db.delete("user1", "name=?" ,new String[]{"tornadomeet"});
        }

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
}

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class DatabaseHelper extends SQLiteOpenHelper {

    private static final int  VERSON = 1;//默認的數(shù)據(jù)庫版本

    //繼承SQLiteOpenHelper類的類必須有自己的構(gòu)造函數(shù)
    //該構(gòu)造函數(shù)4個參數(shù)，直接調(diào)用父類的構(gòu)造函數(shù)。其中第一個參數(shù)為該類本身；第二個參數(shù)為數(shù)據(jù)庫的名字；
    //第3個參數(shù)是用來設(shè)置游標對象的，這里一般設(shè)置為null；參數(shù)四是數(shù)據(jù)庫的版本號。
    public DatabaseHelper(Context context, String name, CursorFactory factory, int verson){
        super(context, name, factory, verson);
    }

    //該構(gòu)造函數(shù)有3個參數(shù)，因為它把上面函數(shù)的第3個參數(shù)固定為null了
    public DatabaseHelper(Context context, String name, int verson){
        this(context, name, null, verson);
    }

    //該構(gòu)造函數(shù)只有2個參數(shù)，在上面函數(shù) 的基礎(chǔ)山將版本號固定了
    public DatabaseHelper(Context context, String name){
        this(context, name, VERSON);
    }

    //該函數(shù)在數(shù)據(jù)庫第一次被建立時調(diào)用
    @Override
    public void onCreate(SQLiteDatabase arg0) {
        // TODO Auto-generated method stub
        System.out.println("create a sqlite database");
        //execSQL()為執(zhí)行參數(shù)里面的SQL語句，因此參數(shù)中的語句需要符合SQL語法,這里是創(chuàng)建一個表
        arg0.execSQL("create table user1(id int, name varchar(20))");
    }

    @Override
    public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
        // TODO Auto-generated method stub
        System.out.println("update a sqlite database");
    }

}

    <Button
        android:id="@+id/create_database"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:text="@string/create_database"
        />

    <Button
        android:id="@+id/update_database"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_above="@id/create_database"
        android:layout_alignParentLeft="true"
        android:text="@string/update_database" />

    <Button
        android:id="@+id/insert"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_above="@id/update_database"
        android:layout_alignParentLeft="true"
        android:text="@string/insert" />

    <Button
        android:id="@+id/update"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_above="@id/insert"
        android:layout_alignParentLeft="true"
        android:text="@string/update" />

    <Button
        android:id="@+id/query"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_above="@id/update"
        android:text="@string/query"
        />
    <Button
        android:id="@+id/delete"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_above="@id/query"
        android:text="@string/delete"
        />

</RelativeLayout>