addProduct method Null safety

void addProduct(
  1. {required Product product,
  2. double? amount,
  3. int? quantity}
)

Implementation

void addProduct({required Product product, double? amount, int? quantity}) {
  if (product.payload[EAPropertyKey.PRODUCT_AMOUNT] == null && amount != null) product.setAmount(amount);
  if (product.payload[EAPropertyKey.PRODUCT_QUANTITY] == null && quantity != null) product.setQuantity(quantity);

  products.add(product);
  payload[EAPropertyKey.ESTIMATE_PRODUCTS] = products;
}