Question

这是我的DateBaseHelper public Cursor 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();

    }

...我用方法

进行测验活动

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......当我不想显示随机问题时，我编辑sql，只需添加SORT BY RANDOM（）LIMIT 10 而我的问题与答案混在一起......

任何人都可以知道解决方案如何获得随机问题而不重复？以及如何避免问题和答案中的混合数据？

Answer 1

你可以在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。我会标记这个问题已经用过1.您可以查询数据库，只返回该字段为0的问题。如果没有问题可用0（它们都已被使用）只需重置所有值该列为0，所有问题同样可用。

如果您有多个会话，这将有所帮助，并希望确保随着时间的推移，所有问题都会受到影响。

我假设您将答案存储在与问题相同的行中。

我会首先进行查询，以获得1个尚未使用的问题/答案对。然后，当然，将其标记为已使用。我会用它作为“问题”。然后我会针对3或4个问题/答案对进行第二次查询，不用担心它们是否被使用。拿出那些错误的答案，然后将它们与正确的答案混合在一起，形成一个多项选择题。

Android如何获取随机sqlite数据？

1 个答案: