如何按日期按升序对数组列表进行排序？

Question

我希望按日期按升序排序待办事项列表。你能帮我吗，我是android领域的初学者enter link description here

Answer 1

尝试按日期的升序和降序

  Collections.sort(arrayList, byDate);

方法升序和降序

     static final Comparator<HomeModel> byDate = new Comparator<HomeModel>() {
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy,MM,dd");

    public int compare(HomeModel ord1, HomeModel ord2) {
        Date d1 = null;
        Date d2 = null;
        try {
            d1 = sdf.parse(ord1.eventdate);
            d2 = sdf.parse(ord2.eventdate);
        } catch (ParseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }


        //return (d1.getTime() > d2.getTime() ? -1 : 1);     //descending
       return (d1.getTime() > d2.getTime() ? 1 : -1);     //ascending
    }
    };

Answer 2

 getReports() {
            return this.http.get(GlobalVariable.BASE_API_URL + 'report/l', {headers: this.headers}).map(res => res.json());
        }

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