Not able to use the updated value -- Flutter - dart

Question

I'm updating the totalPayable value in else if, but I'm not able to use the updated value anywhere in the code when I call getOrder(). Is it an API problem or what can anyone help me with the code?
else if (isOrderInitiated == false){
getCleintOrderFromApi();
debugPrint("ifelse" + totalPayable.toString());
}
getClientOrderFromApi() {
orders.clear();
totalPayable = 0.0;
api.getCleintOrder().then((list) {
list.forEach((order) {
if(order.is_placed) {
order.status = ORDER_STATUS[0];
} else if(!order.is_placed) {
order.status = ORDER_STATUS[2];
}
debugPrint("ORDER_STATUS from remote" + order.status);
for (var j = 0; j < order.items.length; j++) {
FoodItemOrder item = order.items[j];
totalPayable = totalPayable + item.unitPrice * item.quantity;
debugPrint(" total payable in order "+ totalPayable.toString());
}
orders.add(order);
debugPrint("itemsin order"+orders.last.items.length.toString());
});
currentOrderList.clear();
currentOrderList.addAll(orders);
orderItemsSink.add(orders);
});
}
}
The debugPrint in getClientOrderFromApi() is showing the updated result, but in else if debugPrint(" ifelse "+ totalPayable.toString()); it is not showing the updated value which is why wherever I use totalPayable it is not showing the desired value.

Answer 1

Future<List<Order>> getCleintOrder() async {
MakeOrder clientOrderRequest = MakeOrder(); //currentCafe;
clientOrderRequest.caffeID = currentCafe.caffeId;
clientOrderRequest.tableidtimestamp = currentUser.tableIdTimestamp;
// offset = 160;
String url = BASE_URL + BASE_URL_GET_CLIENT_ORDER;
debugPrint("requesting getCleintOrder --- \n" +
url +
"\n " +
clientOrderRequest.toClietnOrderJson().toString());
var response = await http
.post(
url,
headers: {
HttpHeaders.contentTypeHeader: 'application/json',
// HttpHeaders.authorizationHeader : ''
},
body: json.encode(clientOrderRequest.toClietnOrderJson()),
)
.catchError(
(error) {
////debugPrint(error.toString());
return false;
},
);
var jsonObj = json.decode(response.body);
////debugPrint(jsonObj.toString());
List<Order> orders = [];
try {
jsonObj.forEach((newJson) {
List<Order> orderList = (newJson["orders"] as List)
.map((neworderJson) => Order.fromJSON(neworderJson))
.toList().cast<Order>();
orders.addAll(orderList);
});
} catch (e) {
////debugPrint(e.toString());
}
// debugPrint("total client orders " + orders.length.toString());
return orders;
}
This is my api call for refernece.