inlay_gen

Code generator for the inlay add-to-app framework. It reads annotated Dart schema files and produces type-safe route and store classes for Dart, Kotlin, and Swift, so navigation and shared state never rely on arbitrary strings crossing the platform boundary.

How it works

1. You write plain Dart schema files (specs only - never imported by app code) annotated with inlay annotations.
2. inlay_gen parses them and generates matching typed classes for all three languages.
3. The generated Dart compiles into your Flutter module; the generated Kotlin and Swift compile into the native hosts.
4. A schema fingerprint is embedded in every language's output, so a module and a host built from different schema revisions fail loudly instead of silently corrupting data.

Annotations

// A Flutter screen reachable from native or other Flutter screens.
// Declare `result:` to get typed result plumbing (pushForResult / popWithResult).
@InlayFlutterRoute('/counter', result: int)
class CounterPage {
  const CounterPage({this.seed});
  final int? seed;
}

// A Flutter dialog rendered over a native screen in a transparent container.
@InlayFlutterDialog('/confirm-delete/:itemId', result: bool)
class ConfirmDeleteDialog {
  const ConfirmDeleteDialog({required this.itemId});
  final String itemId;
}

// A native screen reachable from Flutter.
@InlayNativeRoute(result: String)
class NativeAboutPage {
  const NativeAboutPage({required this.appVersion});
  final String appVersion;
}

// A typed store on top of inlay's cross-engine key-value storage.
@InlayStore(key: 'user_preferences')
class UserPreferencesStore {
  const UserPreferencesStore({
    @InlayStoreKey() required this.userId, // scopes the store per key
    this.darkMode = false,
    this.tags = const [],
  });

  final String userId;
  final bool darkMode;
  final List<String> tags;
}

Supported field types: bool, int, double, num, String, Uint8List, enums, annotated data classes, List<T>, Map<K, V>, and nested combinations.

Configuration (inlay.yaml)

Place an inlay.yaml in your Flutter module:

routes: lib/inlay/routes.dart
stores: lib/inlay/stores.dart

dart:
  output: lib/src/generated/

kotlin:
  output: native/android/src/main/kotlin/com/example/generated/
  package: com.example.generated

swift:
  output: native/ios/Classes/Generated/

Running

As a standalone CLI:

dart run inlay_gen:inlay_gen --config inlay.yaml

Or as a build_runner builder:

dart run build_runner build

Outputs

• Dart - sealed FlutterRoute / FlutterDialogRoute hierarchies for exhaustive pattern matching, per-route encode/decode, typed result helpers, native route wrappers, typed store classes with immutable snapshots and copyWith.
• Kotlin - route data classes, an abstract NativeRouteHandler with typed on* methods, typed store wrappers with containsChanges.
• Swift - route structs conforming to FlutterRoute/FlutterDialogRoute, a NativeRouteHandler class, typed store structs with containsChanges(in:).

See the inlay documentation for how the generated code is used, and the example module for a complete schema.

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🛠️ Maintained by LeanCode

This package is built with 💙 by LeanCode. We are top-tier experts focused on Flutter Enterprise solutions.

Why LeanCode?

• Creators of Patrol – the next-gen testing framework for Flutter.

• Production-Ready – We use this package in apps with millions of users.

• Full-Cycle Product Development – We take your product from scratch to long-term maintenance.