How to parse JSON object from a website into an arraylist in android

Question

How can I parse a JSON object from a weblink into Android and store the different values into ArrayLists?

The JSON object of users looks like the below. It comes fro

Answer 1

DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(HttpUtil.BASIC_URL
                + HttpUtil.SUBSCRIPTION_URL);
        try{
            if (cookie != null) {
               // httpClient.setCookieStore(LoginJsonUtil.cookie);
                List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>(2);
                nameValuePair.add(new BasicNameValuePair("uid",
                        uid));
                nameValuePair.add(new BasicNameValuePair("subscriptionslist[pageindex]",
                        subscriptionslist_pageindex));
                nameValuePair.add(new BasicNameValuePair("subscriptionslist[recordlimit]",
                        subscriptionslist_recordlimit));
                httpPost.setEntity(new UrlEncodedFormEntity(nameValuePair));

Answer 2

You can use the native JSONObject and JSONArray present on the Android SDK here : https://developer.android.com/reference/org/json/JSONObject.html

There is a method named JSONObject(String json) that allow you to do something like this (not tested) :

//creating your json object from your strong
JSONObject jsonObject = new JSONObject(yourString);
JSONArray users = jsonObject.getJSONArray("users");//this two lines throws a JSONException so put try{}catch{} block
for(JSON user in users)
{
        JSONObject currentUser = users.get(i);
        //insert yout user inside your ArrayList here
}

Answer 3

Assuming you have a class that can store the results and appropiate constructor you can use code like below, using this json.org library for Java,

import org.json.*;

ArrayList<Users> users = new ArrayList<Users>();

JSONObject o = new JSONObject(jsonString);
JSONArray arr = obj.getJSONArray("Users");
for (int i = 0; i < arr.length(); i++)
{
   JSONObject user = arr.getJSONObject(i);

   users.add(new Users(user.getString("name"),user.getDouble("lat"),user.getDouble("lon")));  

   }

}

Answer 4

Use GSON library to parse JSON to java class. It is very simple to use.

Gson gson = new Gson();
Response response = gson.fromJson(jsonLine, Users.class);

Generated model example:

   public class Users {

       @SerializedName("Users")
       @Expose
       public List<User> Users = new ArrayList<User>();
    }


    public class User {

       @SerializedName("name")
       @Expose
       public String name;

       @SerializedName("lon")
       @Expose
       public double lon;

       @SerializedName("lat")
       @Expose
       public double lat;

   }

Answer 5

You can create a Model class from your data model like:

public class DataTemplate{

public final List<User> Users;

public DataTemplate(List<User> Users){
    this.Users = Users;
}

public static class User{
    public final String name;
    public final double lon;
    public final double lat;

    public User(String name, double lon, double lat){
        //initialize elements
    }
} }

After that take a look at GSON library. Using that you can simply import the data as:

DataTemplate getTemplate(String path){
    try {
        return new Gson().fromJson(new InputStreamReader(dataFromURLRequest),  DataTemplate.class);
    } catch (Exception e) {}

After this, just directly retrieve the list from DataTemplate.