Does Flutter throw an Unhandled Exception when setState() or markNeedsBuild() is called during build?

    import 'package:flutter/material.dart';
import 'package:flutter_html/flutter_html.dart';
import 'package:get/get.dart';
import 'package:logger/logger.dart';

import '../controllers/checkout_controller.dart';

class CheckoutView extends StatelessWidget {
  @override
  CheckoutView({super.key});
  CheckoutController controller = Get.put(CheckoutController());
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Finalizar Pedido'),
        centerTitle: true,
      ),
      body: SingleChildScrollView(
        child: GetBuilder<CheckoutController>(builder: (_) {
          Logger().d(controller.isLoading);
          if (controller.isLoading) {
            // Show loading indicator or placeholder while data is being fetched
            return const Center(child: CircularProgressIndicator());
          } else {
            // Build the checkout UI using the fetched data
            final billingAddress = controller.billing;
            final shippingAddress = controller.shipping;

            return Column(
              children: [
                const ListTile(
                  title: Text(
                    'Endereço de Cobrança:',
                    style: TextStyle(
                      fontSize: 18,
                      fontWeight: FontWeight.bold,
                    ),
                  ),
                ),
                ListTile(
                  title: Text(
                    '${billingAddress['address_1']}, ${billingAddress['address_2']}n'
                    '${billingAddress['city']}, ${billingAddress['state']}n'
                    '${billingAddress['postcode']}',
                  ),
                ),
                const SizedBox(height: 16),
                const ListTile(
                  title: Text(
                    'Endereço de entrega:',
                    style: TextStyle(
                      fontSize: 18,
                      fontWeight: FontWeight.bold,
                    ),
                  ),
                ),
                ListTile(
                  title: Text(
                    '${shippingAddress['address_1']}, ${shippingAddress['address_2']}n'
                    '${shippingAddress['city']}, ${shippingAddress['state']}n'
                    '${shippingAddress['postcode']}',
                  ),
                ),
                const ListTile(
                  title: Text(
                    'Pagamento',
                    style: TextStyle(
                      fontSize: 18,
                      fontWeight: FontWeight.bold,
                    ),
                  ),
                ),
                ListView.builder(
                  shrinkWrap: true,
                  physics: const BouncingScrollPhysics(),
                  itemCount: controller.paymentMethods.length,
                  itemBuilder: (context, index) {
                    final paymentMethod = controller.paymentMethods[index];
                    return RadioListTile(
                      title: Text(paymentMethod.title),
                      subtitle: Html(data: paymentMethod.description),
                      value: paymentMethod.id,
                      groupValue: controller.selectedPaymentMethod,
                      onChanged: (value) =>
                          controller.setSelectedPaymentMethod(value),
                    );
                  },
                ),
                const ListTile(
                  title: Text(
                    'Frete',
                    style: TextStyle(
                      fontSize: 18,
                      fontWeight: FontWeight.bold,
                    ),
                  ),
                ),
                const ListTile(
                  title: Text('Frete grátis.'),
                ),
                const ListTile(
                  title: Text(
                    'Observações',
                    style: TextStyle(
                      fontSize: 18,
                      fontWeight: FontWeight.bold,
                    ),
                  ),
                ),
                Padding(
                  padding: const EdgeInsets.all(8.0),
                  child: Container(
                    decoration: BoxDecoration(
                      border: Border.all(
                        color: Colors.grey,
                        width: 1.0,
                      ),
                      borderRadius: BorderRadius.circular(4.0),
                    ),
                    child: TextFormField(
                      decoration: const InputDecoration(
                        labelText: 'Suas observações sobre o pedido',
                        border: InputBorder
                            .none, // Remove the default border from the input field
                        contentPadding: EdgeInsets.symmetric(
                            horizontal: 10.0, vertical: 8.0),
                      ),
                      // onChanged: (value) => controller.setCustomerNote(value),
                    ),
                  ),
                ),
                ElevatedButton(
                  onPressed: () => controller.doCheckout(),
                  child: const Text('Finalizar pedido'),
                )
              ],
            );
          }
        }),
      ),
    );
  }
}

and in checkout_controller.dart:

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:logger/logger.dart';
import 'package:polina/services/api_service.dart';
import 'package:wp_json_api/models/responses/wp_user_info_response.dart' as md;

class CheckoutController extends GetxController {
  final ApiService apiService = Get.find();
  late Map<String, dynamic> checkoutData;
  late List<dynamic> paymentMethods;
  String selectedPaymentMethod = 'cod';
  String customerNote = '';
  bool isLoading = true;
  var billing = {};
  var shipping = {};

  @override
  void onInit() {
    fetchCheckoutData();
    super.onInit();
  }

  @override
  void onReady() {
    super.onReady();
  }

  @override
  void onClose() {
    super.onClose();
  }

  fetchCheckoutData() async {
    isLoading = true;
    update();
    paymentMethods = await apiService.getPaymentMethod();
    checkoutData = await apiService.getCheckout();
    await loadAddresses();
    isLoading = false;
    update();
  }

  Future<void> loadAddresses() async {
    var u = await apiService.getUserInfo();
    List<md.MetaData>? m = u.data?.metaData;
    billing['first_name'] = m
        ?.firstWhere((element) => element.key == 'billing_first_name')
        .value![0];
    billing['last_name'] = m
        ?.firstWhere((element) => element.key == 'billing_last_name')
        .value![0];
    billing['company'] =
        m?.firstWhere((element) => element.key == 'billing_company').value![0];
    billing['address_1'] = m
        ?.firstWhere((element) => element.key == 'billing_address_1')
        .value![0];
    billing['address_2'] = m
        ?.firstWhere((element) => element.key == 'billing_address_2')
        .value![0];
    billing['city'] =
        m?.firstWhere((element) => element.key == 'billing_city').value![0];
    billing['postcode'] =
        m?.firstWhere((element) => element.key == 'billing_postcode').value![0];
    billing['country'] =
        m?.firstWhere((element) => element.key == 'billing_country').value![0];
    billing['state'] =
        m?.firstWhere((element) => element.key == 'billing_state').value![0];
    //shipping
    shipping['first_name'] = m
        ?.firstWhere((element) => element.key == 'shipping_first_name')
        .value![0];
    shipping['last_name'] = m
        ?.firstWhere((element) => element.key == 'shipping_last_name')
        .value![0];
    shipping['company'] =
        m?.firstWhere((element) => element.key == 'shipping_company').value![0];
    shipping['address_1'] = m
        ?.firstWhere((element) => element.key == 'shipping_address_1')
        .value![0];
    shipping['address_2'] = m
        ?.firstWhere((element) => element.key == 'shipping_address_2')
        .value![0];
    shipping['city'] =
        m?.firstWhere((element) => element.key == 'shipping_city').value![0];
    shipping['postcode'] = m
        ?.firstWhere((element) => element.key == 'shipping_postcode')
        .value![0];
    shipping['country'] =
        m?.firstWhere((element) => element.key == 'shipping_country').value![0];
    shipping['state'] =
        m?.firstWhere((element) => element.key == 'shipping_state').value![0];
    Logger().d(billing.toString());
    Logger().d(shipping.toString());
  }

  void setSelectedPaymentMethod(String value) {
    selectedPaymentMethod = value;
    update();
  }

  void setCustomerNote(String value) {
    customerNote = value;
  }

  doCheckout() async {
    isLoading = true;
    var checkout2 = {
      "billing_address": billing,
      "shipping_address": shipping,
      "customer_note": customerNote,
      "create_account": false,
      "payment_method": selectedPaymentMethod,
      "payment_data": [],
      "shipping_lines": [
        {
          "method_id": "free_shipping",
          "method_title": "Frete grátis",
          "total": 0
        }
      ]
    };
    apiService.doCheckout(checkout2).then((order) {
      isLoading = false;
      Get.snackbar(
        'Sucesso',
        'Pedido realizado.',
        snackPosition: SnackPosition.BOTTOM,
        backgroundColor: Colors.green,
        colorText: Colors.white,
      );
      //go to order details passing order id
      Get.offNamedUntil(
        '/order',
        ModalRoute.withName('/'),
        arguments: {'id': order['order_id']},
      );
    });
  }
}