private void fetchTransactions() { transactionViewFlipper.setDisplayedChild(0); StringRequest stringRequest = new StringRequest(POST, GET_ALL_MERCHANT_TRANSACTIONS, new Response.Listener<String>() { @Override public void onResponse(String response) { try { JSONObject jsonObject = new JSONObject(response); if (jsonObject.getString("status").equals("SUCCESS")) { JSONArray jsonArray = new JSONArray(jsonObject.getString("result")); final Multimap<String, ArrayList<MerchantTransactionDetails>> multimap = LinkedListMultimap.create(); final ArrayList<String> monthNames = new ArrayList<>(); for (int i = 0; i < jsonArray.length(); i++) { monthTransactions = new ArrayList<>();