How to add data into a json array instead of a ArrayList?

Question

What I am trying to do is add a Map into an ArrayList and then into a JsonArray. What I intend to do is directly add the maps into the json array.

//Initialize the ArrayList,Map and Json array
private ArrayList<Map<String, String>> itemData = new ArrayList<>();
private Map<String, String> itemselected = new HashMap<>();
JSONArray itemSelectedJson = new JSONArray();



 private void selectedItems() {
    if(invEstSwitch.isChecked())
    {
        billType = textViewEstimate.getText().toString();
    }else{
        billType = textViewInvoice.getText().toString();
    }

    itemselected.put("custInfo",custSelected.toString());
    itemselected.put("invoiceNo", textViewInvNo.getText().toString());
    itemselected.put("barcode", barCode.getText().toString());
    itemselected.put("desc", itemDesc.getText().toString());
    itemselected.put("weight", weightLine.getText().toString());
    itemselected.put("rate", rateAmount.getText().toString());
    itemselected.put("makingAmt", makingAmount.getText().toString());
    itemselected.put("net_rate", netRate.getText().toString());
    itemselected.put("itemTotal", itemtotal.getText().toString());
    itemselected.put("vat", textViewVat.getText().toString());
    itemselected.put("sum_total", textViewSum.getText().toString());
    itemselected.put("bill_type", billType);
    itemselected.put("date", textViewCurrentDate.getText().toString());

    //Add the map to the Array
    itemData.add(index, itemselected);
    itemSelectedJson= new JSONArray(Arrays.asList(itemData));
    index++;
}

Solution 1

You can do this way:

JSONArray jRootArray = new JSONArray();

        for (int i = 1; i <= 20; i++) {
            JSONObject jInnerObject = new JSONObject();
            try {
                jInnerObject.put(String.valueOf(i), "Hello "+i);
            } catch (JSONException e) {
                e.printStackTrace();
            }

            jRootArray.put(jInnerObject);
        }

        Log.i("JRootArray", jRootArray.toString());

Hope this will help you.

Solution 2

Try this:

private Map<String, String> itemselected = new HashMap<>();   

private void selectedItems() {

    JSONArray itemSelectedJson = new JSONArray();

    // Retrieve all keys
    Set<String> keys = itemselected.keySet(); 

    // Add items to JSONArray as JSONObjects
    for(String key : keys) {
        itemSelectedJson.put(
            new JSONObject().put(key, itemselected.get(key))
        );
    }
}

This way, you won't have to pass by an ArrayList to fill your JSONArray. Then, you can get your JSON string simply by calling the toString() method on the JSON array:

String jsonString = itemSelectedJson.toString();