navigator.push

class CategoriesScreen extends StatelessWidget {
  const CategoriesScreen({super.key});

  void selectCategory(BuildContext context) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (ctx) => MealsScreen(
          title: 'Some title',
          meals: [],
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("Pick your category")),
      body: GridView(
        padding: const EdgeInsets.all(24),
        gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
          crossAxisCount: 2,
          childAspectRatio: 3 / 2,
          crossAxisSpacing: 20,
          mainAxisSpacing: 20,
        ),
        children: [
          for (final category in availableCategories)
            CategoryGridItem(
              category: category,
              selectCategory: () {
                selectCategory(context);
              },
            )
        ],
      ),
    );
  }
}