如何从以下类型的JSONObject中获取数据？没有JSONArray

Question

我从JSONObject获得了Firebase的学位。

没有任何JSONArray作为回应。

怎样才能得到带循环的主JSONObject 。？

下面的JSON响应是否有效？还是我要转换成JSONArray？

如果有JSONObject，我知道如何获得内部JSONArray。

{
    "Data": {
        "inner_data": {
            "key1": {
                "chapter": "Chapter 1",
                "key": "key",
                "weight": 1
            },
            "key2": {
                "chapter": "Chapter 2",
                "key": "-KMa5xai7vMQtaDZ0b31",
                "weight": 2
            }
        }
    },
    "Demo": {
        "inner_demo": {
            "key1": {
                "chapter": "Chapter 1",
                "key": "key",
                "weight": 1
            },
            "key2": {
                "chapter": "Chapter 2",
                "key": "-KMa5xai7vMQtaDZ0b31",
                "weight": 2
            }
        }
    },
    "Test": {
        "inner_test1": {
            "-KMa9JFjKuDNgf313Bzc": {
                "key": "-KMa9JFjKuDNgf313Bzc",
                "time": "10:33",
                "topic": "Circles",
                "url": "https://www.youtube.com/watch?v=yLVsv9kO5C8",
                "weight": 1
            }
        },
        "-inner_test2": {
            "-KMa95pUP3bKtnoQaPg4": {
                "key": "-KMa95pUP3bKtnoQaPg4",
                "time": "15:26",
                "topic": "Linear Equations in two Variables",
                "url": "https://www.youtube.com/watch?v=Wpr3tddDw9s",
                "weight": 1
            }
        },
        "-inner_test3": {
            "-KMa8i5mU9HUapf-wGDU": {
                "key": "-KMa8i5mU9HUapf-wGDU",
                "time": "05:38",
                "topic": "Measurement of volumes",
                "url": "https://www.youtube.com/watch?v=mbFwgu4xx40",
                "weight": 1
            }
        },
        "inner_demo_test": {
            "key1": {
                "chapter": "Chapter 1",
                "key": "key",
                "weight": 1
            },
            "key2": {
                "chapter": "Chapter 2",
                "key": "-KMa5xai7vMQtaDZ0b31",
                "weight": 2
            }
        }
    }
}

注:这只是回应总数的10%。

Answer 1

您提供的json是有效的，如果您知道密钥，您可以简单地说

obj.getJSONObject("key");

如果您不知道密钥，可以使用迭代器

JSONObject j=new JSONObject();
    Iterator<String> iterator=j.keys();
    while (iterator.hasNext())
    {
        String key=iterator.next();
       JSONObject newObj= j.getJSONObject(key);
    }

获取嵌套对象。