Question

I’m currently trying to put a twitter feed into my app and currently everything works except when I try to get the image url field from the JSON returned.

Here is my code to parse the JSON:

      public ArrayList<Tweet> getTweets() {
      String searchUrl =
          "http://twitter.com/statuses/user_timeline/vogella.json";

      ArrayList<Tweet> tweets =
            new ArrayList<Tweet>();

      HttpClient client = new  DefaultHttpClient();
      HttpGet get = new HttpGet(searchUrl);

      ResponseHandler<String> responseHandler =
            new BasicResponseHandler();

      String responseBody = null;
      try {
        responseBody = client.execute(get, responseHandler);
      } catch(Exception ex) {
        ex.printStackTrace();
      }

      JSONObject jsonObject = null;

      Log.e("", "responseBody = " + responseBody);


    JSONArray arr = null;
    try {
        arr = new JSONArray(responseBody);
    } catch (JSONException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }

      for (int i = 0; i < arr.length(); i++) {
            try {
                jsonObject = arr.getJSONObject(i);
            } catch (JSONException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            Tweet tweet = null;
            try {
                tweet = new Tweet(
                      jsonObject.getString("profile_image_url"),
                      jsonObject.getString("text"),
                      jsonObject.getString("created_at")
                );
            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            tweets.add(tweet);
        }

      return tweets;
    }

And here is the error I get:

02-14 00:19:18.672: W/System.err(809): org.json.JSONException:JSONObject["profile_image_url"] not found.

Despite the “profile_image_url” being present – click the link to see the JSON – LINK. Everything else in the feed appears to be retrievable so why cant I get the image url?

Answer 1

Your jsonObject variable refers to the top level array element of your response, which contains elements like in_reply_to_status_id, geo, etc. The profile_image_url property is not a property in that top level array element, but rather a child element of the user property.

[
    {
        "in_reply_to_status_id":null,
        "in_reply_to_user_id_str":null,
        ...
        "geo":null,
        "user":
            {   
                "profile_background_image_url":"http:\/\/a3.twimg.com\/profile_background_images\/112136794\/twilk_background_4c1620bca9ed3.jpg",
                ...
            }
    },
    ...
]

To access the profile_background_image_url, you would have to do something roughly like the following:

JSONObject userObject = jsonObject.getJSONObject ("user");
String url = userObject.getString("profile_image_url");