数据库的创建以及添加查询方法

//dao层
public class Dao {
private Context context;
private final SQLiteDatabase db;

public Dao(Context context) {
    this.context = context;
    Sqlite sqlite=new Sqlite(context);
    db = sqlite.getWritableDatabase();
}
public long insert(String table, String nullColumnHack, ContentValues values){
    return db.insert(table, nullColumnHack, values);
}
public Cursor query(String table, String[] columns, String selection,
                    String[] selectionArgs, String groupBy, String having,
                    String orderBy){
    return db.query(table, columns, selection,
            selectionArgs, groupBy, having,
             orderBy);
}

}
//sqlite
public class Sqlite extends SQLiteOpenHelper {
public Sqlite(Context context) {
super(context, “bw.db”, null, 1);
}

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL("create table chen(id integer primary key autoincrement,title text,reader text)");
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}

}

//添加方法

//查询方法
Cursor query = dao.query(“chen”, null, null, null, null, null, null);
if (query.moveToFirst()){
do {
Log.e(“wzq”,“dowhile”);
String title = query.getString(query.getColumnIndex(“title”));
String reader = query.getString(query.getColumnIndex(“reader”));

                //Toast.makeText(getActivity(),list.toString(),Toast.LENGTH_LONG).show();
                list.add(new Jsonbean.DataBean("",title,reader,""));

            }while (query.moveToNext());
        }