private Map<String,String> mapDate;
//正序
mapDate=new TreeMap<String, String>(new Comparator<String>() {
            @Override
            public int compare(String lhs, String rhs) {
                // TODO Auto-generated method stub
                return lhs.compareTo(rhs);
            }
        });
//倒序
mapDate=new TreeMap<String, String>(new Comparator<String>() {
            @Override
            public int compare(String lhs, String rhs) {
                // TODO Auto-generated method stub
                return rhs.compareTo(lhs);
            }
        });
List<String> mSections=new mSections = new ArrayList<String>();
Collections.sort(mSections);