Failed assertion: line 5140 pos 12: '_history.isNotEmpty': is not true.

[murtaza-bhaisaheb]

import 'package:flutter/material.dart';
import 'package:line_icons/line_icons.dart';
import 'package:tuza/constants/global_variables.dart';
import 'package:tuza/features/admin/screens/add_product_screen.dart';
import 'package:tuza/features/admin/services/admin_services.dart';
import 'package:tuza/models/product.dart';

class ProductsScreen extends StatefulWidget {
  const ProductsScreen({Key? key}) : super(key: key);

  @override
  State<ProductsScreen> createState() => _ProductsScreenState();
}

class _ProductsScreenState extends State<ProductsScreen> {
  final AdminServices adminServices = AdminServices();
  List<Product>? productList;

  @override
  void initState() {
    super.initState();
    fetchAllProducts();
  }

  fetchAllProducts() async {
    productList = await adminServices.fetchAllProducts(context);
    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    return productList == null ? const CircularProgressIndicator() : Scaffold(
      body: const Center(child: Text('Products'),),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          Navigator.of(context).pushNamed(AddProductScreen.routeName);
        },
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.circular(20.0),
        ),
        backgroundColor: GlobalVariables.backgroundColor,
        tooltip: "Add a product",
        child: Container(
          decoration: BoxDecoration(
            borderRadius: BorderRadius.circular(18.0),
            border: Border.all(color: GlobalVariables.selectedNavBarColor)
          ),
          child: Padding(
            padding: const EdgeInsets.all(12.0),
            child: Icon(
              LineIcons.plus, color: GlobalVariables.selectedNavBarColor,
            ),
          ),
        ),
      ),
      floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
    );
  }
}

[darshankawar]

@murtaza-bhaisaheb The code sample you shared contains third party plugin and custom code, but in order to narrow down the issue to framework, please provide complete minimal reproducible code sample without any third party plugin that triggers the assertion you are reporting.

Thanks.

[murtaza-bhaisaheb]

// A function to fetch the list:

Future<List>? fetchAllProducts(BuildContext context) async { final UserProvider userProvider = Provider.of(context, listen: false); List productList = []; try { http.Response res = await http.get(Uri.parse('$uri/admin/get-products'), headers: { 'Content-Type': 'application/json; charset=UTF-8', 'x-auth-token': userProvider.user.token, });

  httpErrorHandle(
      response: res,
      context: context,
      onSuccess: () {
        for (int i = 0; i < jsonDecode(res.body).length; i++) {
          productList.add(
            Product.fromJson(
              jsonEncode(
                jsonDecode(res.body)[i],
              ),
            ),
          );
        }
        showSnackBar(context, 'Product added successively');
        Navigator.of(context).pop();
      });
} catch (e) {
  showSnackBar(context, e.toString());
}

return Future.value(productList);

}

// In the UI:

Future<List?>? fetchAllProducts() async { productList = await adminServices.fetchAllProducts(context); return Future.value(productList); // setState(() {}); }

// And in build method:

FutureBuilder( future: fetchAllProducts(), builder: (BuildContext context, AsyncSnapshot snapshot) { switch (snapshot.connectionState) { case ConnectionState.waiting: return const Text('Loading....'); default: if (snapshot.hasError) { return Text('Error: ${snapshot.error}'); } else { return const Scaffold( body: Text('Loaded'), ); } }

[murtaza-bhaisaheb]

Loading appears for 1 second and then black screen appears

[darshankawar]

The updated code you shared still contains third party plugin provider, so I suggest you to ask this question on support channels like StackOverflow.

Closing from here for now.

[github-actions[bot]]

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.