java - 如何将多个列表放入一个列表中？

Question

好的，所以我需要使用 Java 将许多不同的列表放入一个列表中。这是重要的代码。

String jsonText = buffer.toString(); // gets what the URL returns as JSON


                JSONObject obj = new JSONObject(jsonText); // using JSONObject to pass to a JSONArray to search for the JSON

                List<List<String>> allInfo = new ArrayList();// list to put all the returned information
                List<String> innerList = new ArrayList();
                JSONArray linemanques = obj.getJSONArray("linemanques"); //selects the array to read from


                for (int i = 0; i < linemanques.length(); i++) {
                    JSONObject questionParts = linemanques.getJSONObject(i);
                    quesnum = questionParts.getString("quesnum"); // all of questionParts.getString() are for getting the data in the JSONArray
                    questype = questionParts.getString("questype");
                    question = questionParts.getString("question");
                    ans1 = questionParts.getString("ans1");
                    ans2 = questionParts.getString("ans2");
                    ans3 = questionParts.getString("ans3");
                    ans4 = questionParts.getString("ans4");
                    correctans = questionParts.getString("correctans");
                    category = questionParts.getString("category");
                    notes = questionParts.getString("notes");
                    flag = questionParts.getString("flag");

                    innerList.add(quesnum);
                    innerList.add(questype);
                    innerList.add(question);
                    innerList.add(ans1);
                    innerList.add(ans2);
                    innerList.add(ans4);
                    innerList.add(correctans);
                    innerList.add(category);
                    innerList.add(notes);
                    innerList.add(flag);

                    allInfo.add(innerList);
                }

                return allInfo;

如上所示，我将一个名为innerList 的List 放入另一个List 中，该List 的类型为名为allInfo 的List。在 for 循环中，我获取正在使用的 JSONArray 的长度，并将元素添加到 innerList。然后，我将 innerList 添加到 allInfo 中，然后将其返回。

顺便说一下，这里是 JSON。

{
    "error": false,
    "message": "Request successfully completed",
    "linemanques": [
        {
            "quesnum": 1,
            "questype": 1,
            "question": "This is question #1",
            "ans1": "This is answer 1",
            "ans2": "This is answer 2\r\n",
            "ans3": "This is answer 3\r\n\r\n\r\n",
            "ans4": "This is answer 4",
            "correctans": "ans4",
            "notes": "This is a note",
            "category": "2",
            "flag": "ans4"
        },
        {
            "quesnum": 2,
            "questype": 2,
            "question": "This is question #2",
            "ans1": "This is Q2 ans 1",
            "ans2": "This is Q2 ans2",
            "ans3": "This is Q2 ans3",
            "ans4": "This is Q2 ans4",
            "correctans": "ans2",
            "notes": "This is Q2 note 1",
            "category": "5",
            "flag": "ans2"
        },
        {
            "quesnum": 3,
            "questype": 6,
            "question": "gkjhgjkgkg",
            "ans1": "ghdfhdghfd",
            "ans2": "Tuituiyt",
            "ans3": "Tiuytui9",
            "ans4": "Tauitui.247",
            "correctans": "ans2",
            "notes": "Article iutuC",
            "category": "5",
            "flag": "ans2"
        },
        {
            "quesnum": 7,
            "questype": 2,
            "question": " how many",
            "ans1": "isi",
            "ans2": "thiis\\r\\n",
            "ans3": "yes",
            "ans4": "no",
            "correctans": "yes",
            "notes": "refer back to yes",
            "category": "0",
            "flag": "yes"
        },
        {
            "quesnum": 8,
            "questype": 2,
            "question": " how many",
            "ans1": "isi",
            "ans2": "thiis",
            "ans3": "yes",
            "ans4": "no",
            "correctans": "yes",
            "notes": "refer back to yes",
            "category": "0",
            "flag": "yes"
        },
        {
            "quesnum": 9,
            "questype": 2,
            "question": "How many apples can I eat in one day?",
            "ans1": "42 apples",
            "ans2": "6 apples",
            "ans3": "89 apples",
            "ans4": " 42 oranges",
            "correctans": "ans2",
            "notes": "try eating apples",
            "category": "8",
            "flag": "ans2"
        },
        {
            "quesnum": 10,
            "questype": 2,
            "question": " how many",
            "ans1": "isi",
            "ans2": "thiis\\r\\n\\r\\n\\r\\n",
            "ans3": "yes",
            "ans4": "no",
            "correctans": "yes",
            "notes": "refer back to yes",
            "category": "0",
            "flag": "yes"
        }
    ]
}

这是我希望的数组结构：

allInfo {
    innerList {
        JSONObject
        JSONObject
        JSONObject
    }
    innerList {
        JSONObject
        JSONObject
        JSONObject
    }
    innerList {
        JSONObject
        JSONObject
        JSONObject
    }
    innerList {
        JSONObject
        JSONObject
        JSONObject
    }
    innerList {
        JSONObject
        JSONObject
        JSONObject
    }
    innerList {
        JSONObject
        JSONObject
        JSONObject
    }
}

但相反，这就是我最终的结果（我认为）：

allInfo {
    innerList {
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
        JSONObject
    }
}

它应该在一个列表中创建多个列表，以便我可以调用对它的访问并在 TextView 中设置文本，如下所示：

textView.setText(allInfo.get(2).get(4)); //example

标签： javaandroidjson

Answer 1

我猜如果你把这条线List<String> innerList = new ArrayList();放在for循环中，它每次都会正确初始化innerList。