Sqlite教程(1) SQLiteOpenHelper

首先，创建DbHelper对象，继承SQLiteOpenHelper。

Configuration是自行创建的工具类，里面都是App的一些环境设置。

public class DbHelper extends SQLiteOpenHelper {

    private Configuration config = new Configuration();

    private static DbHelper Instance = null;
    private Context context;

    // 饿汉式
    public static DbHelper getInstance(Context context) {
        if (Instance == null) {
            Instance = new DbHelper(context.getApplicationContext());
        }
        return Instance;
    }

    /*
    *    @param [Context]context，来自DAO的上下文图
    */
    private DbHelper(Context context) {
        super(context, Configuration.DB_NAME, null, Configuration.DB_VERSION);
        this.context = context;
    }

    public void onCreate(SQLiteDatabase db) {
        db.execSQL(config.CREATE_USER_TABLE);
        db.execSQL(config.CREATE_POST_TABLE);
    }

    /*
    *    call this method if you need to update SQlite but I really don't suggest to use this
    */
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL(" DROP TABLE IF EXISTS "+config.DB_USER);
        db.execSQL(" DROP TABLE IF EXISTS "+config.DB_POST);
    }

}