how to get data from inner json array in android

Question

please I am trying to get the URL from the JSON array thumbnail_images and it is inside another array which is medium_large, how can I get data from the second array. I have been able to get the URL from this JSON

"attachments": [

{
    "id": 367,
    "url": "http://street2view.com/wp-content/uploads/2017/01/mmm.png",

with this code:

JSONArray attachments = post.getJSONArray("attachments");
if (null != attachments && attachments.length() > 0) {
   JSONObject attachment = attachments.getJSONObject(0);
   if (attachment != null)
      item.setAttachmentUrl(attachment.getString("url"));
}

so how can I get the data from an inner array like in this code how can I get the URL

"thumbnail_images": {
    "medium_large": {
        "url": "http://street2view.com/wp-content/uploads/2017/01/mmm.png",
        "width": 749,
        "height": 400

Answer 1

this is based on your example that does not have "thumbnail_images" as an array, but instead it's just a property

JSONObject images = post.getJSONObject("thumbnail_images");
JSONObject mediumLarge = images.getJSONObject("medium_large");
String url = mediumLarge.optString("url");

Answer 2

i've got it!

            JSONObject images = post.getJSONObject("thumbnail_images");
            JSONObject mediumLarge = images.getJSONObject("medium_large");
            item.setAttachmentUrl(mediumLarge.optString("url"));

thanks to @classicalConditioning for the Hint.