CODEWITHSUNDEEP
javaandroidjson
Darshan Gowda
Darshan Gowda

Reputation: 5216

How to access JSON data with multiple array objects : android

I am stuck in getting the data from the JSON file with multiple data sets.

{
  "status": "ok",
  "count": 3,
  "count_total": 661,
  "pages": 133,
  "posts": [
    {
      "id": 20038,
      "type": "post",
      "slug": "xperia-launcher-download",
      "url": "http:\/\/missingtricks.net\/xperia-launcher-download\/",
      "status": "publish",
      "title": "Download Xperia Launcher app for Android (Latest Version)"
    },
    {
      "id": 94,
      "type": "post",
      "slug": "top-free-calling-apps-of-2014-year",
      "url": "http:\/\/missingtricks.net\/top-free-calling-apps-of-2014-year\/",
      "status": "publish",
      "title": "Best Free Calling Apps for Android November 2014"
    },
    {
      "id": 98,
      "type": "post",
      "slug": "top-free-calling-apps-of-2016-year",
      "url": "http:\/\/missingtricks.net\/top-free-calling-apps-of-2016-year\/",
      "status": "publish",
      "title": "Best Free Calling Apps for Android December 2016"
    }
  ]
}

I need to access the title, url and status from the above JSON file.

@Override
    protected void onPostExecute(String result) {
        //this method will be running on UI thread

        pdLoading.dismiss();
        List<DataFish> data = new ArrayList<>();
        pdLoading.dismiss();
        try {
            JSONArray jArray = new JSONArray(result);
            // Extract data from json and store into ArrayList as class objects
            for (int i = 0; i < jArray.length(); i++) {
                JSONObject json_data = jArray.getJSONObject(i);
                DataFish fishData = new DataFish();
                fishData.status = json_data.getString("status");                 
                fishData.title = json_data.getString("url");                  
                fishData.sizeName = json_data.getString("title");
                data.add(fishData);
            }
        } catch (JSONException e) {
            Toast.makeText(JSonActivity.this, e.toString(), Toast.LENGTH_LONG).show();
            Log.d("Json","Exception = "+e.toString());
        }
    }

I am getting a JSONException with the above code.

What should I do to access the title,status and url from the JSON File?

Upvotes: 2

Views: 4439

Answers (2)

Nirmal Bajpai
Nirmal Bajpai

Reputation: 229

You can validate your JSON here.

If entire JSON getJsonObject() is not working, then you should parse JSON objects & array in multiple arrays then use them.

Upvotes: 0

Pavneet_Singh
Pavneet_Singh

Reputation: 37404

You have to fetch your JSONArray which is inside a JSONObject , so create a JSONObject and fetch your array with index "posts"

1.) result is a JSONObject so create a JSONObject

2.) Fetch your JSONArray with index value as "posts"

3.) Now simply traverse array objects by fetching it through index

        JSONObject jObj = new JSONObject(result);
        JSONArray jArray = jObj.getJSONArray("posts");

        // Extract data from json and store into ArrayList as class objects
        for (int i = 0; i < jArray.length(); i++) {
            JSONObject json_data = jArray.getJSONObject(i);


            DataFish fishData = new DataFish();
            fishData.status = json_data.getString("status");

            fishData.title = json_data.getString("url");

            fishData.sizeName = json_data.getString("title");


            data.add(fishData);
        }

Note : i don't know weather it is a sample response with shorter version though your json object should ends with } not with , .

[{"id":20038,"type":"post","slug":"xperia-launcher-download","url":"http://missingtricks.net/xperia-launcher-download/","status":"publish","title":"Download Xperia Launcher app for Android (Latest Version)",

//  ^^^ there should be a } not a , to end json
// so make sure to do the correction so it will look like =>  ...st Version)"},

{"id":94,"type":"post","slug":"top-free-calling-apps-of-2014-year","url":"http://missingtricks.net/top-free-calling-apps-of-2014-year/","status":"publish","title":"Best Free Calling Apps for Android November 2014", ]

Improvements :

you can use optString to avoid null or non-string value if there is no mapping key

This has two variations

Get an optional string associated with a key. It returns the defaultValue if there is no such key.

 public String optString(String key, String defaultValue) {

  fishData.status = json_data.optString("status","N/A");
 // will return "N/A" if no key found

or To get empty string if no key found then simply use

  fishData.status = json_data.optString("status");
 // will return "" if no key found where "" is an empty string

Upvotes: 4

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