Total price calculating from cart

  @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_cart);

        //Firebase
        database = FirebaseDatabase.getInstance();
        requests = database.getReference("Requests");

        //init
        recyclerView = findViewById(R.id.listCart);
        recyclerView.setHasFixedSize(true);
        layoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(layoutManager);

        txtTotalPrice = findViewById(R.id.total);
        btnPlace = findViewById(R.id.btnPlaceOrder);

        btnPlace.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (cart.size() > 0)
                    showAlertDialog();
                else
                    Toast.makeText(Cart.this, "Your Cart is Empty", Toast.LENGTH_SHORT).show();
            }
        });

        loadListFood();
    }

 private void showAlertDialog() {
        AlertDialog.Builder alertDialog = new AlertDialog.Builder(Cart.this);
        alertDialog.setTitle("One more step!");
        alertDialog.setMessage("Enter your address: ");

        final EditText edtAddress = new EditText(Cart.this);
        LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.MATCH_PARENT,
                LinearLayout.LayoutParams.MATCH_PARENT
        );
        edtAddress.setLayoutParams(lp);
        alertDialog.setView(edtAddress); // Add edit text to alert dialog.
        alertDialog.setIcon(R.drawable.ic_shopping_cart_black_24dp);

        alertDialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                // Create new Request
                Request request = new Request(
                        Common.currentUser.getPhone(),
                        Common.currentUser.getName(),
                        edtAddress.getText().toString(),
                        txtTotalPrice.getText().toString(),
                        cart
                );

                int stock = 0;


                // Submit to Firebase Database
                // We Will using System.CurrentMilli to Key
                requests.child(String.valueOf(System.currentTimeMillis()))
                        .setValue(request);
                //Delete cart
                new Database(getBaseContext()).cleanCart();
                Toast.makeText(Cart.this, "Thank you for ordering!", Toast.LENGTH_SHORT).show();
                finish();
            }
        });

        alertDialog.setNegativeButton("No", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();
            }
        });

        alertDialog.show();
    }

    private void loadListFood() {
        cart = new Database(this).getCarts();
        adapter = new CartAdapter(cart, this);
        adapter.notifyDataSetChanged();
        recyclerView.setAdapter(adapter);

        //Calculation of total price
        int total = 0;
        for(Order order:cart)
            total+=(Integer.parseInt(order.getPrice())) * (Integer.parseInt(order.getQuantity()));



        Locale locale = new Locale("en","PH");
        NumberFormat fmt = NumberFormat.getCurrencyInstance(locale);

        txtTotalPrice.setText(fmt.format(total));
    }