All 7 Named Routes & Navigator 2.0 (Router API) questions
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What are named routes in Flutter, and how do they let you navigate to a specific screen simply by referencing a genuinely simple string identifier rather than needing to directly construct that particular widget yourself? What is Navigator 2.0, and how does its own declarative Router based approach genuinely differ from the earlier imperative push and pop based navigation approach used by Navigator 1.0? How does the go_router package provide a considerably higher level, considerably more genuinely convenient declarative routing API built directly on top of Flutter's own more complex, considerably more verbose lower level Navigator 2.0 APIs? How do you properly implement nested navigation using a considerably more complex router structure, such as one genuinely needed to properly support a bottom navigation bar where each individual tab genuinely maintains its own entirely separate independent navigation stack? How can you properly implement route guards using go_router's own redirect functionality to properly control access to specific protected routes based on a user's own current genuine authentication state? How do you properly test navigation logic, including verifying that a specific given route correctly and reliably navigates to its own expected screen and that a redirect properly and correctly occurs when genuinely expected?
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Flutter › Named Routes & Navigator 2.0 (Router API)

How do you actually properly pass arguments to a destination screen when using Navigator.pushNamed, and how does that destination screen then actually properly retrieve those particular passed arguments?

Beginner

Answer

Passing arguments through a named route involves providing an arguments parameter to Navigator.pushNamed containing whatever specific data the destination screen genuinely actually needs, and that destination screen then retrieves those particular passed arguments by properly calling ModalRoute.of context settings arguments, typically casting that particular result to its own genuinely correct expected specific type, letting you pass data such as a specific product identifier through to a corresponding detail screen without needing to directly reference that destination widget's own constructor parameters at all.
Navigator.pushNamed(context, '/product-detail', arguments: productId);

// Within the destination screen
final productId = ModalRoute.of(context)!.settings.arguments as String;
Real-world example A product list screen navigates to a shared product detail route, passing the specific tapped product's own unique identifier as an argument, letting that destination screen properly retrieve and correctly use that exact same passed identifier to fetch and display the correct specific product's own details.

Common follow-ups: What genuinely happens if the destination screen attempts to cast those particular passed arguments to the wrong incorrect expected type?;Is there a genuinely safer, more type checked alternative approach to passing arguments compared to this particular dynamic method?

Custom Widgets & Reusable Components;Dart Null Safety
All 7 Named Routes & Navigator 2.0 (Router API) questions