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这是我的 DateBaseHelper 公共游标 getQuestionsFromQuizID(int quizID){

             Integer quiz = Integer.valueOf(quizID);

             return myDataBase.rawQuery("select * from Questions where quizID ="+quiz.toString(), null );

     }

     public Cursor getAnswersFromQuestionID(int questionID, int quizID){

             Integer question = Integer.valueOf(questionID);
             Integer quiz = Integer.valueOf(quizID);

             return myDataBase.rawQuery("select * from Answers where questionID = "+question.toString()+" and quizID = "+quiz.toString(), null );
     }

    public Boolean isAnswerCorrect(int answerID) {

            Integer answer = Integer.valueOf(answerID);
            int correctBit;

            Cursor cursor = myDataBase.rawQuery("select * from Answers where _id ="
                            + answer.toString(), null);

            cursor.moveToFirst();
            correctBit = cursor.getInt(3);

            if (correctBit == 1) {
                    return true;
            } else {
                    return false;
            }

    }

    public int getQuestionCountByQuizID(int quizID){

            Integer quiz = Integer.valueOf(quizID);

            Cursor cursor = myDataBase.rawQuery("select * from Questions where quizID ="+quiz.toString(), null);

            cursor.moveToFirst();

            return cursor.getCount();

    }

...我有测验活动的方法

private void getNextQuestion() { 字符串问题;

            // set question count text at the top of screen using string
            // concatenation
            Integer currentCount = new Integer(curQuestion + 1);
            ((TextView) findViewById(R.id.questioncount)).setText("Question "
                            + currentCount.toString() + " of "
                            + totalQuestionCount.toString());

            // get quizID based on which button was pressed on PickQuizActivity
            int quizID = getIntent().getExtras().getInt("quizID");

            // use returned cursor to get question as string
            Cursor questionCursor = myDbHelper.getQuestionsFromQuizID(quizID);

            questionCursor.moveToPosition(curQuestion);

            // getString(3): gets the zero-indexed column 2 from current row cursor
            // is on
            question = questionCursor.getString(2);

            // update UI to show question pulled from database
            ((TextView) findViewById(R.id.question)).setText(question);

            Cursor answerCursor = myDbHelper.getAnswersFromQuestionID(
                            curQuestion + 1, quizID);

            // set each answer text, there will always be 4 answers
            // also collect questionID for isCorrect check when onClick is called
            answerCursor.moveToFirst();
            ((TextView) findViewById(R.id.answer1)).setText(answerCursor
                            .getString(4));
            answerID1 = answerCursor.getInt(0);

            answerCursor.moveToNext();
            ((TextView) findViewById(R.id.answer2)).setText(answerCursor
                            .getString(4));
            answerID2 = answerCursor.getInt(0);

            answerCursor.moveToNext();
            ((TextView) findViewById(R.id.answer3)).setText(answerCursor
                            .getString(4));
            answerID3 = answerCursor.getInt(0);

            answerCursor.moveToNext();
            ((TextView) findViewById(R.id.answer4)).setText(answerCursor
                            .getString(4));
            answerID4 = answerCursor.getInt(0);

            // increment question counter, will be used to retrieve next question
            curQuestion++;

            // set flag for last question reached
            if (questionCursor.isLast()) {
                    lastQuestionReached = true;
            }
    }

所以...当我不显示随机问题时,我编辑 sql,只需添加 SORT BY RANDOM() LIMIT 10,我的问题就会与答案混淆...

任何人都可以知道如何获得随机问题而不重复的解决方案吗?以及如何避免混合来自问题和答案的数据?

4

1 回答 1

1

您可以在 sqlite 数据中有一个额外的列,如果不使用,则为 0,如果使用,则为 1。我会标记该问题已与 1 一起使用。您可以查询数据库以仅返回该字段为 0 的问题。如果没有可用的问题为 0(它们都已被使用),只需重置所有值该列为 0,所有问题都同样可用。

如果您有多个会话,并且希望确保随着时间的推移,所有问题都得到解决,这将有所帮助。

我假设您将答案存储在与您的问题相同的行中。

我会首先进行查询以获取 1 个未使用的问题/答案对。然后,当然,将其标记为已使用。我会用它作为“问题”。然后我会再次查询 3 或 4 个问题/答案对,不用担心它们是否被使用。选择那些错误的答案,并随机将它们与多项选择题的正确答案混合。

于 2013-04-19T01:13:52.073 回答