Question

我对Trivia游戏感到担忧，我需要为用户回答的每个正确问题做得分++，我怎样才能在SQLITe中做到这一点？这是我的DBHELPER 我想通过他的用户名为用户名添加1，有人可以帮我吗？

private static final String DATABASE_NAME = "ScoreUsers.db";

public DBHelper(Context context ) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
    //All necessary tables you like to create will create here

    String CREATE_TABLE_STUDENT = "CREATE TABLE IF NOT EXISTS " + User.TABLE  + "("
            + User.KEY_ID  + " INTEGER PRIMARY KEY AUTOINCREMENT ,"
            + User.KEY_name + " TEXT, "
            + User.KEY_score + " INTEGER, "
            + User.KEY_pass + " TEXT )";

    db.execSQL(CREATE_TABLE_STUDENT);

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("DROP TABLE IF EXISTS " + User.TABLE);

    onCreate(db);

}

public int insert(User user) {

    //Open connection to write data
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(User.KEY_ID, user.ID);
    values.put(User.KEY_pass,user.Password);
    values.put(User.KEY_name, user.name);
    values.put(User.KEY_score,user.score);

    // Inserting Row
    long student_Id = db.insert(User.TABLE, null, values);
    db.close(); // Closing database connection
    return (int) student_Id;
}

/*public boolean updateScore(String name)
{
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(User.KEY_ID, user.ID);
    values.put(User.KEY_pass,user.Password);
    values.put(User.KEY_name, user.name);
    values.put(User.KEY_score,user.score);

    db.update(User.TABLE,values,User.KEY_name + "=?",new String[]{username});
    db.close();
    return true;
}*/


public User getUserById(int Id){
    SQLiteDatabase db = this.getReadableDatabase();
    String selectQuery =  "SELECT  " +
            User.KEY_ID + "," +
            User.KEY_name + "," +
            User.KEY_pass +
            " FROM " + User.TABLE
            + " WHERE " +
            User.KEY_ID + "=?";// It's a good practice to use parameter ?, instead of concatenate string;// It's a good practice to use parameter ?, instead of concatenate string

    //int iCount =0;
    User user = new User();

    Cursor cursor = db.rawQuery(selectQuery, new String[] { String.valueOf(Id) } );

    if (cursor.moveToFirst()) {
        do {
            user.ID =cursor.getInt(cursor.getColumnIndex(User.KEY_ID));
            user.name =cursor.getString(cursor.getColumnIndex(User.KEY_name));
            user.Password  =cursor.getString(cursor.getColumnIndex(User.KEY_pass));

        } while (cursor.moveToNext());
    }

    cursor.close();
    db.close();
    return user;
}

public boolean loginByUserName(User user)
{
    String pass="";
    SQLiteDatabase db = this.getReadableDatabase();
    String selectQuery =  "SELECT  " +
            User.KEY_name + "," +
            User.KEY_pass +
            " FROM " + User.TABLE
            + " WHERE " +
            User.KEY_name + "=?";

    Cursor cursor = db.rawQuery(selectQuery, new String[] { String.valueOf(user.name) } );

    if (cursor.moveToFirst()) {
        do {
            pass  =cursor.getString(cursor.getColumnIndex(User.KEY_pass));
        } while (cursor.moveToNext());
    }
    if(pass.equals(user.Password)) return true;
    return false;
}


public ArrayList<String> getUserList() {
    //Open connection to read only
    SQLiteDatabase db = this.getReadableDatabase();
    String selectQuery =  "SELECT  " +
            User.KEY_name + "," +
            User.KEY_pass + "," +
            User.KEY_score +
            " FROM " + User.TABLE;

    //Student student = new Student();
    ArrayList<String> userList1 = new ArrayList<String>();

    Cursor cursor = db.rawQuery(selectQuery, null);
    // looping through all rows and adding to list

    if (cursor.moveToFirst()) {
        do {

            userList1.add(cursor.getString(cursor.getColumnIndex(User.KEY_name)) +" "+ cursor.getString(cursor.getColumnIndex(User.KEY_pass))+" "+cursor.getString(cursor.getColumnIndex(User.KEY_score)));


        } while (cursor.moveToNext());
    }

    cursor.close();
    db.close();
    return userList1;

}

public void deleteByID(int ID) {

    SQLiteDatabase db = this.getWritableDatabase();
    // It's a good practice to use parameter ?, instead of concatenate string
    db.delete(User.TABLE, User.KEY_ID + "= ?", new String[] { String.valueOf(ID) });
    db.close(); // Closing database connection
}

public void deleteByName(String name) {

    SQLiteDatabase db = this.getWritableDatabase();
    // It's a good practice to use parameter ?, instead of concatenate string
    db.delete(User.TABLE, User.KEY_name + "= ?", new String[] { String.valueOf(name) });
    db.close(); // Closing database connection
}

public void clearTable()   {
    SQLiteDatabase db = this.getWritableDatabase();
}
}

Answer 1

您可以使用SQLite dbHelper中的更新。

尝试此命令

 UPDATE User.TABLE SET User.KEY_score= User.KEY_score + 1 WHERE User.KEY_ID = {enter the one you want to update score for}

SQLite Android studio，更新值

1 个答案: