Question

我能够获取json响应，在arraylist中添加了响应
当我尝试比较2个arraylist时，arraylist2值没有变化。
我做了什么：

json解析：

for (int i = 0; i < array.length(); i++) {
                    JSONObject obj = array.getJSONObject(i);
                    id = obj.getString("alert_id");


                    map.put("alert_id", id);

                    Log.d("map", map.toString());
                    arraylist1.add(map);

                       Log.e("asdasd", arraylist1.toString());
                }

- 比较：

for (int i = 0; i < arraylist.size(); i++) {
                for (int j = 0; j < arraylist1.size(); j++) {
                    if (!(arraylist.get(i).get("id")).equals((arraylist1.get(j).get("id")))) {
                        //Checking whether the last value in the list..
                        if (j == (arraylist1.size() - 1)) {
                            unCommonList.add(arraylist.get(i).get("alert_id"));


                        } else {

                        }
                    }
                }
            }

- 输出：

- 每次arraylist2保持不变，arraylist1正在改变，但arraylist2值不是

- 这是我的arraylist2：

[{abcd=100, id=79, createdate=2016-03-14 03:59:43, defge=2012310, 123123xyzw=alpha}, {abcd=11230, id=79, createdate=2016-03-14 03:59:43, defge=201231230, xyzw=alpasdha}, {abcd=10452430, id=79, createdate=2016-03-14 03:59:43, defge=12346, xyzw=alasdpha}, {abcd=1za00, id=79, createdate=2016-03-14 03:59:43, defge=212312300, xyzw=alpdsaha}, {abcd=112312300, id=79, createdate=2016-03-14 03:59:43, defge=21231200, xyzw=alpsqwha}, {abcd=123123, id=79, createdate=2016-03-14 03:59:43, defge=201231230, xyzw=alpqwreha}, {abcd=112312300, id=79, createdate=2016-03-14 03:59:43, defge=212312300, xyzw=alpyjha}, {abcd=101231230, id=79, createdate=2016-03-14 03:59:43, defge=200, xyzw=alpha}]

Answer 1

for (int i = 0; i < arraylist.size(); i++) {
            for (int j = 0; j < arraylist1.size(); j++) {
                if (!(arraylist.get(i).get("id")).equals((arraylist1.get(j).get("id")))) {
                    //Checking whether the last value in the list..
                    if (j == (arraylist1.size() - 1)) {
                        unCommonList.add(arraylist.get(i).get("alert_id"));


                    } else {

                    }
                }else{
                           break;
                              }
            }
        }

Answer 2

好的，为了获得不匹配的元素，你可以试试这段代码

ArrayList<Integer> results = new ArrayList<>();


for (Person person2 : arrayList2) {

    boolean found = false;
    for (Person person1 : arrayList1) {
    if (person2.id == person1.id) {
        found = true;
    }
}
if (!found) {
    results.add(person2.id);
}
}

在比较2个arraylist时得到相同的值

2 个答案: