如何从没有数组名称的Android中的json中获取数据？

Question

我想从这个链接获取一个url：

 "http://graph.facebook.com/10202459285618351/picture?type=large&redirect=false"

它给出结果：

{ " data ":{ " URL ":" https://FBC dn-profile-a . akamaihd . net/hprofile-AK-xa P1/t 1.0-1/s200x 200/10342822 _ 10202261537234765 _ 3194866551853134720 _ n . jpg "，" is_silhouette": false } }

我试过了，

private class GetContacts extends AsyncTask<Void, Void, Void> {

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        // Showing progress dialog
        pDialog = new ProgressDialog(AccountActivity.this);
        pDialog.setMessage("Please wait...");
        pDialog.setCancelable(false);
        pDialog.show();

    }

    @Override
    protected Void doInBackground(Void... arg0) {
        // Creating service handler class instance
        ServiceHandler sh = new ServiceHandler();

        String jsonStr = sh.makeServiceCall(fbPicURL, ServiceHandler.GET);

        Log.d("Response: ", "> " + jsonStr);

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

                // Getting JSON Array node
                fbRealURL = jsonObj.getString("url");


                    // Phone node is JSON Object
                    Toast.makeText(AccountActivity.this, fbRealURL,
                            Toast.LENGTH_LONG).show();
                    // tmp hashmap for single contact

                }
             catch (JSONException e) {
                e.printStackTrace();
            }
        } else {
            Log.e("ServiceHandler", "Couldn't get any data from the url");
        }

        return null;
    }

    @Override
    protected void onPostExecute(Void result) {
        super.onPostExecute(result);
        // Dismiss the progress dialog
        if (pDialog.isShowing())
            pDialog.dismiss();
        /**
         * Updating parsed JSON data into ListView
         * */
        Toast.makeText(AccountActivity.this, fbRealURL,
                Toast.LENGTH_LONG).show();
    }

}

但是返回null，它没有崩溃…

Answer 1

您必须先像这样获取数据对象：

     try {
            JSONObject jsonObj = new JSONObject(jsonStr);


            fbRealURLObj = jsonObj.getJSONObject("data");

            fbRealURL = fbRealURLObj.getString("url");

                // Phone node is JSON Object
                Toast.makeText(AccountActivity.this, fbRealURL,
                        Toast.LENGTH_LONG).show();
                // tmp hashmap for single contact

            }