Question

我正在开发一款应用。我希望对ArrayList进行排序。我面临的问题是，每当我有重复的条目时，排序都会失败并且应用程序崩溃。

截至目前的布局是：

虽然我希望以下列方式得到结果：

我已编写以下代码进行排序。

private void sortAlphaNumeric() {
        /* Take a temporary list to store the original list */

        /*
         * Remove any white spaces in the question number as it might
         * interfere in sorting
         */
        String[] trimmedArray = new String[m_quesNumber.size()];
        for (int i = 0; i < m_quesNumber.size(); i++) {
            trimmedArray[i] = m_quesNumber.get(i).replace(" ", "");
        }
        m_quesNumber = new ArrayList<String>();
        for (int i = 0; i < trimmedArray.length; i++) {
            m_quesNumber.add(trimmedArray[i]);
        }

        ArrayList<String> temp_quesNumber = new ArrayList<String>(
                m_quesNumber);


        /* Sort the original list */
        Collections.sort(m_quesNumber, new AlphanumComparator());


        /* Temporary arrays */
        String[] temp_prevQuesId = new String[m_quesId.size()];
        String[] temp_quesMaxMarks = new String[m_quesMaxScore.size()];
        Integer[] temp_quesOptional = new Integer[m_quesOptional.size()];

        for (int i = 0; i < m_quesNumber.size(); i++) {
            int old_position = temp_quesNumber.indexOf(m_quesNumber.get(i));

            temp_prevQuesId[i] = m_quesId.get(old_position);
            temp_quesMaxMarks[i] = m_quesMaxScore.get(old_position);
            temp_quesOptional[i] = m_quesOptional.get(old_position);
        }

        m_quesId = new ArrayList<String>();
        m_quesMaxScore = new ArrayList<String>();
        m_quesOptional = new ArrayList<Integer>();

        for (int i = 0; i < temp_prevQuesId.length; i++) {
            m_quesId.add(temp_prevQuesId[i]);

            m_quesMaxScore.add(temp_quesMaxMarks[i]);
            m_quesOptional.add(temp_quesOptional[i]);
        }


    }

Answer 1

制作一个类似......的模型类。

class Result {
    String qNo;
    int marksScored;
    int maximumMarks;
    ...
}

并将Result的arrayList设为

List<Result> results = new ArrayList<>();

添加所需数据，然后按照给定代码对其进行排序。

Collections.sort(results, new Comparator<Result>() {
            @Override
            public int compare(Result lhs, Result rhs) {
                return lhs.qNo.compareToIgnoreCase(rhs.qNo);
            }
        });

Answer 2

只需使用此代码而不是所有代码。

ArrayList<ArrayList<String>> data; //then initialize it

// and pass it here. Sort based on column 0
Collections.sort(data, new Comparator<ArrayList<String>>() {
    @Override
    public int compare(ArrayList<String> row1, ArrayList<String> row2) {
        return row1.get(0).compareTo(row2.get(0));
    }
});

在Android中对ArrayLists进行排序

2 个答案: