Android read JSONArray into a JSONArray

Question

How can i read a json array that contains a json array this is my json

{
    "product": {
        "name": "myApp",
        "config": [
            {
                "grade": "elementary school",
                "courses": [
                    {
                        "name": "Math",
                        "teacher": "David"
                    }
                ]
            }
        ]
    }
}

for example how can i read "config" and then courses, to generate a list that show me elementary school and then if i tap in that name my app show me the name of the course and the name of the teacher

Answer 1

Well first, this is not a JSONArray; it's a JSONObject. A JSONArray is denoted by opening and closes braces ([ and ], respectively), while a JSONObject is denoted by opening/closing brackets ({ and }, respectively).

Now, to answer your question as to how to parse it...

Let's assume you have:

String s = your_json_data;

Now, to parse that:

JSONObject jsonObj = new JSONObject(s);

JSONObject productJson = jsonObject.getJSONObject("product"); // May want to consider using optJSONObject for null checking in case your key/value combination doesn't exist

String name = productJson.getString("name"); // myApp

Now that should get you started with the basic stuff... Let's go over iterating through an actual JSONArray:

JSONArray configJsonArray = productJson.getJSONArray("config");
for(int configIterator = 0; configIterator < configJsonArray.length(); configIterator++){
    JSONObject innerConfigObj = configJsonArray.getJSONObject(configIterator);
    String configGrade = innerConfigObj.getString("grade");

    JSONArray courseJsonArray = innerConfigObj.getJSONArray("courses");
    for(int courseIterator = 0; courseIterator < courseJsonArray.length(); courseIterator++){
        JSONObject innerCourseObj = innerCourseObj.getJSONObject(courseIterator);
        String courseName = innerCourseObj.getString("name");
        String courseTeacher = innerCourseObj.getString("teacher");
    }
}

That should allow you to iterate through them.