How to filter data from Json in android?

Question

i am getting the data in json form like

{\"Users\":[
{\"category_id\":\"1\",\"user_email\":\"a@a.com\"},
{\"category_id\":\"5\",\"user_ema         


        

Answer 1

finally i got the answer..

private void applySearch(String searchStr) {
            ArrayList<User> searchEmail = new ArrayList<User>();


            for (int i = 0; i < UserArray.size(); i++) {
                if(UserArray.get(i).getcategory_id().toLowerCase().contains(searchStr.toLowerCase())) {
                    searchEmail.add(UserArray.get(i));
                }
            }

           // set the adapter hear 

        }

without for loop it is not possible ... UserArray is my array list content user object

Answer 2

Use JSONObject from the Android SDK. Check out the documentation here:

http://developer.android.com/reference/org/json/JSONObject.html

You basically need to parse the JSON, then loop through and only operate on the items with the specified category id.

For larger data sets, using JsonReader will be more performant if written properly.

http://developer.android.com/reference/android/util/JsonReader.html

Answer 3

First you need to create your variables in your activity

//URL to get JSON
private static String url = "your url to parse data";

//JSON Node Names
private static final String TAG_USERS = "users";
private static final String TAG_CATEGORY_ID = "category_id";
private static final String TAG_USER_EMAIL = "user_email";

// Data JSONArray
JSONArray users = null;

//HashMap to keep your data
ArrayList<HashMap<String, String>> userList;

inside onCreate() function instantiate your userList

userList = new ArrayList<HashMap<String, String)>>();

then you need to parse your data and populate this ArrayList in doInBackground() function

//Create service handler class instance
ServiceHandler sh = new ServiceHandler();

//Url request and response
String jsonStr = sh.makeServiceCall(url, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);

if(jsonStr != null) {
    try {
        JSONObject jsonObj = new JSONObject(jsonStr);

        //Get Json Array Node
        users = jsonObj.getJSONArray(TAG_USERS);

        // Looping through all data
        for(int i = 0; i < users.length(); i++) {
            JSONObject u = users.getJSONObject(i);

            String category_id = u.getString(TAG_CATEGORY_ID);
            String user_email = u.getString(TAG_USER_EMAIL);

            // Temporary HashMap for single data
            HashMap<String, String> user = new HashMap<String, String>();

            // Adding each child node to Hashmap key -> value
            user.put(TAG_CATEGORY_ID, category_id);
            user.put(TAG_USER_EMAIL, user_email);

            //Adding user to userList
            userList.add(user);
        }
    }catch (JSONException e) {
        e.printStackTrace();
    }
} else {
    Log.e("ServiceHandler", "Couldn't get any data from url");
}

Now you have your data stored in your userList. You can use your userList however you want. To get the category_id field in the list you can use this syntax

// i being the counter of your loop
String catId = userList.get(i).get("category_id");
if(catId == 3) {
    ... your code
}