qr_example.dart

import 'package:flutter/material.dart';
import 'package:qlevar_router/qlevar_router.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
     return MaterialApp.router(
      routeInformationParser: QRouteInformationParser(),
      routerDelegate: QRouterDelegate(
        AppRoutes().routes,
        initPath: '/products',
      ),
    );
  }
}


class ProductsPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Material(
      child: Column(
        children: [
          const SizedBox(height: 30),
          Text('ProductsPage'),
          const SizedBox(height: 30),
          Wrap(
            children: List.generate(10, (index) => index.toString())
                .map(
                  (e) => TextButton(
                    child: Padding(
                      padding: const EdgeInsets.all(32.0),
                      child: Text(e),
                    ),
                    onPressed: () {
                      /// Navigate to the singleProductPage route using
                      /// QR.to('/products/$e');
                      /// or
                      QR.toName(AppRoutes.singleProductPage, params: {'id': e});
                    },
                  ),
                )
                .toList(),
          )
        ],
      ),
    );
  }
}

class SingleProductPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Material(
      child: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text('SingleProductPage with id = ${QR.params['id']}'),
            const SizedBox(height: 10),

            ///show only when you recive the `lang` query paramter
            if (QR.params['lang'] != null)
              Text('Selected Langauge  with Lang = ${QR.params['lang']}'),
          ],
        ),
      ),
    );
  }
}


class AppRoutes {
  static String productsPage = 'ProductsPage';
  static String singleProductPage = 'SingleProductPage';

  final routes = [
    QRoute(
      name: productsPage,
      path: '/products',
      builder: () => ProductsPage(),
      children: [
        QRoute(
          ///use the name to route using `QR.toName`
          name: singleProductPage,
          path: '/:id',
          builder: () => SingleProductPage(),
        ),
      ],
    ),
  ];
}