无法解析JSON消息:文档为空

Question

我正在做一个购物车系统。我正在试着把添加到清单中的产品价格加起来。当我更新产品数量时，它给了我以下错误:

我使用getx。但我不认为这是一个getx错误。

Unable to parse JSON message: The document is empty.

countTotalPrice() async {
totalPrice = 0.0;
for (var i = 0; i < cartProducts.length; i++) {
totalPrice += cartProducts[i]['total'] as double;
}
update();
}

addToCart(int index) async {
Map data = {
"product_name": productsList[index]['english_name'],
"price": productsList[index]['sale_price'],
"qty": 1,
"total": productsList[index]['sale_price'],
};
cartProducts.add(data);
countTotalPrice();
update();
}

updateQuantity(index, count) {
Map data = cartProducts[index];
data['qty'] = count;
data['total'] = double.parse(data['price']) * data['qty'];
countTotalPrice();
update();
}

Answer 1

try this

data['total'] = double.parse(data['price'].toString()) * double.parse(data['qty'].toString())).toString();