Android对Cursor排序

import java.util.Collections;
import java.util.Comparator;
import java.util.List;

/**
 * Created by XU on 2017/3/2.
 */

public class SortCursor extends CursorWrapper {
    /**
     * Creates a cursor wrapper.
     *
     * @param cursor The underlying cursor to wrap.
     */
    private static final String LOGTAG = \"SortCursor\";
    public static final int SORT_LETTER_BEFORE_NUM = 1;

    private int mSortType;
    private int mPos;

    private Cursor mCursor;
    

    /**
     * @param cursor
     * @param sortType
     */
    public SortCursor(Cursor cursor, int sortType) {
        super(cursor);
        mSortType = sortType;
        mPos = -1;
        mCursor = cursor;
        initSortList();
        EexecuteSortList();
    }

    /**
     * 建立与Cursor对应的索引表
     */
    public  void initSortList() {
        LogUtils.i(LOGTAG, \"56 SortCursor initSortList\");
        int i = 0;
        DOWAApp.mRosterInfoList.clear();
        
        if (mCursor == null || !mCursor.moveToFirst()) {
            return;
        }
        LogUtils.i(LOGTAG, mCursor.getCount() + \"\");
        do {
            RosterInfo rosterInfo = new RosterInfo();
            //sortKey.clearRoster();
            rosterInfo.otherJid = mCursor.getString(mCursor
                    .getColumnIndexOrThrow(RosterConstants.OTHER_JID));
            rosterInfo.alias = mCursor.getString(mCursor
                    .getColumnIndexOrThrow(RosterConstants.ALIAS));
//            sortKey.status_mode = mCursor.getString(mCursor
//                    .getColumnIndexOrThrow(RosterConstants.STATUS_MODE));
//            sortKey.status_message = mCursor.getString(mCursor
//                    .getColumnIndexOrThrow(RosterConstants.STATUS_MESSAGE));
//            sortKey.group = mCursor.getString(mCursor
//                    .getColumnIndexOrThrow(RosterConstants.GROUP));
            rosterInfo.order = i++;

            LogUtils.v(LOGTAG, rosterInfo.toString());
            DOWAApp.mRosterInfoList.add(rosterInfo);
        } while (mCursor.moveToNext());
    }

    /**
     * 对表进行排序
     */
    protected void EexecuteSortList() {
        if (DOWAApp.mRosterInfoList == null || DOWAApp.mRosterInfoList.size() <= 1) {
            return;
        }
        LogUtils.i(LOGTAG, \"DOWAApp.mRosterInfoList.size()=\" + DOWAApp.mRosterInfoList.size());

        for (int i = 0; i < DOWAApp.mRosterInfoList.size(); i++) {
            LogUtils.i(LOGTAG, \"i=\" + i);
            LogUtils.i(LOGTAG, \"DOWAApp.mRosterInfoList.get(i)=\" + DOWAApp.mRosterInfoList.get(i));
            LogUtils.i(LOGTAG, \"DOWAApp.mRosterInfoList.get(i).getAlias()=\" + DOWAApp.mRosterInfoList.get(i).getAlias());
            //DOWAApp.mRosterInfoList.get(i).getOtherJid();
        }
        ComparatorEx comparator = new ComparatorEx();
        Collections.sort(DOWAApp.mRosterInfoList, comparator);

        LogUtils.i(LOGTAG, \"排序后的 列表 DOWAApp.mRosterInfoList.size()=\" + DOWAApp.mRosterInfoList.size());
        for (int i = 0; i < DOWAApp.mRosterInfoList.size(); i++) {
            LogUtils.i(LOGTAG, \"DOWAApp.mRosterInfoList.get(i).getAlias()=\" + DOWAApp.mRosterInfoList.get(i).getAlias());
            //DOWAApp.mRosterInfoList.get(i).getOtherJid();
        }
    }

    public List<RosterInfo> getRostList() {
        return DOWAApp.mRosterInfoList;
    }

    /**
     * 比较
     */
    public class ComparatorEx implements Comparator {
        @Override
        public int compare(  obj1,   obj2) {
            RosterInfo entry1 = (RosterInfo) obj1;
            RosterInfo entry2 = (RosterInfo) obj2;
            switch (mSortType) {
                case SORT_LETTER_BEFORE_NUM:
                    return compareLetterBeforeNumByAlias(entry1, entry2);
                default:
                    return 0;
            }
        }

        /**
         * @param entry1
         * @param entry2
         * @return
         */
        protected int compareLetterBeforeNumByAlias(RosterInfo entry1, RosterInfo entry2) {
            if (entry1.alias == null) {
                entry1.alias = entry1.getOtherJid();
            }
            if (entry2.alias == null) {
                entry2.alias = entry2.getOtherJid();
            }
            String o1 = PinyinUtils.getPingYin(entry1.alias);
            String o2 = PinyinUtils.getPingYin(entry2.alias);
            int c1 = (o1.charAt(0) + \"\").toUpperCase().hashCode();
            int c2 = (o2.charAt(0) + \"\").toUpperCase().hashCode();

            boolean c1Flag = (c1 < \"A\".hashCode() || c1 > \"Z\".hashCode()); // 不是字母
            boolean c2Flag = (c2 < \"A\".hashCode() || c2 > \"Z\".hashCode()); // 不是字母
            if (c1Flag && !c2Flag) {
                return 1;
            } else if (!c1Flag && c2Flag) {
                return -1;
            }
            return o1.toUpperCase().compareTo(o2.toUpperCase());//如果比较的字符串全为英文字母或者全为数字，则按正常比较
        }
    }

    /**
     * 获取列表中每一项的实际位置
     *
     * @param position
     * @return
     */
    protected int getRelativePos(int position) {

        int relativePos = position;
        switch (mSortType) {
            case SORT_LETTER_BEFORE_NUM:
                //LogUtils.i(TAG, \"152 sortcursor position=\"+position);
                relativePos = DOWAApp.mRosterInfoList.get(position).order;
                //LogUtils.i(TAG, \"154 sortcursor relativePos=\"+relativePos);
                //LogUtils.i(TAG, \"relativePos=\" + relativePos);
                break;
            default:
                break;
        }

        //
        //LogUtils.v(LOGTAG, \"ThreadMsgSortCursor-->position-->\" + position +
        //\"  relativePos --->\" + relativePos);
        return relativePos;
    }

    /**
     * @param position
     * @return
     */
    public boolean moveToPosition(int position) {
//        mPos = position;
//        //
//        int order = getRelativePos(position);
//        //LogUtils.i(TAG, \"order=\" + order);
//        return mCursor.moveToPosition(order);

        //LogUtils.i(TAG, \"176 sortcursor DOWAApp.mRosterInfoList.size()=\"+DOWAApp.mRosterInfoList.size());
        //LogUtils.i(TAG, \"177 sortcursor position=\"+position);
        if (position >= 0 && position < DOWAApp.mRosterInfoList.size()) {
            mPos = position;
            int order = getRelativePos(position);
            //int order = DOWAApp.mRosterInfoList.get(position).order;
            return mCursor.moveToPosition(order);
        }
        if (position < 0) {
            mPos = -1;
        }
        if (position >= DOWAApp.mRosterInfoList.size()) {
            mPos = DOWAApp.mRosterInfoList.size();
        }
        return mCursor.moveToPosition(position);
    }

    public boolean moveToFirst() {
        LogUtils.v(LOGTAG, \"ThreadMsgSortCursor---------->moveToFirst------\");
        return moveToPosition(0);
    }

    public boolean moveToLast() {
        LogUtils.v(LOGTAG, \"ThreadMsgSortCursor---------->moveToLast------\");
        return moveToPosition(getCount() - 1);
    }

    public boolean moveToNext() {
        LogUtils.v(LOGTAG, \"ThreadMsgSortCursor---------->moveToNext------mPos=\" + mPos);
        return moveToPosition(mPos + 1);
    }

    public boolean moveToPrevious() {
        LogUtils.v(LOGTAG, \"ThreadMsgSortCursor---------->moveToPrevious------\");
        return moveToPosition(mPos - 1);
    }

    public boolean move(int offset) {
        LogUtils.v(LOGTAG, \"ThreadMsgSortCursor---------->move------\");
        return moveToPosition(mPos + offset);
    }

    public int getPosition() {
        return mPos;
    }

    public void close_() {
        LogUtils.v(LOGTAG, \"ThreadMsgSortCursor---------->close------\");
        mCursor.close();
    }

}