Merge pull request #24 from leancodepl/feat/generic-presentation-event

.github/workflows/bloc_presentation-test.yml

@@ -21,7 +21,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        version: ['3.10.x']
+        version: ['3.10.x', '3.13.x']
 
     defaults:
       run:

.github/workflows/bloc_presentation_test-test.yml

@@ -21,7 +21,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        version: ['3.10.x']
+        version: ['3.10.x', '3.13.x']
 
     defaults:
       run:

packages/bloc_presentation/CHANGELOG.md

@@ -1,3 +1,8 @@
+# 0.4.0
+
+- **BREAKING**: `BlocPresentationMixin` is now generic over the type of the presentation event (see #17)
+- **BREAKING**: removed `BlocPresentationEvent` marker type
+
 # 0.3.0
 
 - Bump minimum Flutter version to `3.10.0` (#22)

packages/bloc_presentation/README.md

@@ -17,7 +17,9 @@ flutter pub add bloc_presentation
 First, create an event which will be emitted:
 
 ```dart
-class FailedToUpvote implements BlocPresentationEvent {
+sealed class CommentCubitEvent {}
+
+class FailedToUpvote implements CommentCubitEvent {
   const FailedToUpvote(this.reason);
 
   final String reason;
@@ -28,7 +30,7 @@ Next, extend your Bloc/Cubit with the presentation mixin which will give you
 access to the `emitPresentation` method:
 
 ```dart
-class CommentCubit extends Cubit<CommentState> with BlocPresentationMixin {
+class CommentCubit extends Cubit<CommentState> with BlocPresentationMixin<CommentState, CommentCubitEvent> {
   // body
 }
 ```
@@ -55,12 +57,13 @@ new states. Then, in the UI code one can react to such events using
 `BlocPresentationListener` or `useBlocPresentationListener`:
 
 ```dart
-BlocPresentationListener<CommentCubit>(
+BlocPresentationListener<CommentCubit, CommentCubitEvent>(
   listener: (context, event) {
-    if (event is FailedToUpvote) {
-      ScaffoldMessenger.of(context)
-        ..hideCurrentSnackBar()
-		..showSnackBar(SnackBar(content: Text(event.reason)));
+    switch (event) {
+      case FailedToUpvote():
+        ScaffoldMessenger.of(context)
+          ..hideCurrentSnackBar()
+          ..showSnackBar(SnackBar(content: Text(event.reason)));
     }
   },
   child: MyWidget(),

packages/bloc_presentation/example/android/build.gradle

@@ -1,12 +1,12 @@
 buildscript {
-    ext.kotlin_version = '1.3.50'
+    ext.kotlin_version = '1.8.21'
     repositories {
         google()
         mavenCentral()
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:4.1.0'
+        classpath 'com.android.tools.build:gradle:7.4.2'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }
@@ -26,6 +26,6 @@ subprojects {
     project.evaluationDependsOn(':app')
 }
 
-task clean(type: Delete) {
+tasks.register("clean", Delete) {
     delete rootProject.buildDir
 }

packages/bloc_presentation/example/android/gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.6.1-all.zip

packages/bloc_presentation/example/lib/comment_cubit.dart

@@ -3,7 +3,8 @@ import 'dart:math';
 import 'package:bloc_presentation/bloc_presentation.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 
-class CommentCubit extends Cubit<CommentState> with BlocPresentationMixin {
+class CommentCubit extends Cubit<CommentState>
+    with BlocPresentationMixin<CommentState, CommentEvent> {
   CommentCubit() : super(const CommentInitialState());
 
   void fetch() {
@@ -32,13 +33,15 @@ class CommentCubit extends Cubit<CommentState> with BlocPresentationMixin {
   }
 }
 
-class FailedToUpvote implements BlocPresentationEvent {
+sealed class CommentEvent {}
+
+class FailedToUpvote implements CommentEvent {
   const FailedToUpvote(this.reason);
 
   final String reason;
 }
 
-class SuccessfulUpvote implements BlocPresentationEvent {
+class SuccessfulUpvote implements CommentEvent {
   const SuccessfulUpvote(this.message);
 
   final String message;

packages/bloc_presentation/example/lib/main.dart

@@ -28,17 +28,18 @@ class MyHomePage extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return BlocPresentationListener<CommentCubit>(
+    return BlocPresentationListener<CommentCubit, CommentEvent>(
       listener: (context, event) {
         // we know we will receive this event once
-        if (event is FailedToUpvote) {
-          ScaffoldMessenger.of(context)
-            ..hideCurrentSnackBar()
-            ..showSnackBar(SnackBar(content: Text(event.reason)));
-        } else if (event is SuccessfulUpvote) {
-          ScaffoldMessenger.of(context)
-            ..hideCurrentSnackBar()
-            ..showSnackBar(SnackBar(content: Text(event.message)));
+        switch (event) {
+          case FailedToUpvote():
+            ScaffoldMessenger.of(context)
+              ..hideCurrentSnackBar()
+              ..showSnackBar(SnackBar(content: Text(event.reason)));
+          case SuccessfulUpvote():
+            ScaffoldMessenger.of(context)
+              ..hideCurrentSnackBar()
+              ..showSnackBar(SnackBar(content: Text(event.message)));
         }
       },
       child: Scaffold(

packages/bloc_presentation/example/pubspec.yaml

@@ -18,7 +18,7 @@ dev_dependencies:
   bloc_test: ^9.1.2
   flutter_test:
     sdk: flutter
-  leancode_lint: '^5.0.0'
+  leancode_lint: ">=5.0.0 <7.0.0"
 
 flutter:
   uses-material-design: true

packages/bloc_presentation/lib/bloc_presentation.dart

@@ -1,4 +1,3 @@
-export 'src/bloc_presentation_event.dart';
 export 'src/bloc_presentation_listener.dart';
 export 'src/bloc_presentation_mixin.dart';
 export 'src/use_bloc_presentation_listener.dart';

packages/bloc_presentation/lib/src/bloc_presentation_listener.dart

@@ -1,4 +1,3 @@
-import 'package:bloc_presentation/src/bloc_presentation_event.dart';
 import 'package:bloc_presentation/src/use_bloc_presentation_listener.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_hooks/flutter_hooks.dart';
@@ -10,15 +9,15 @@ import 'bloc_presentation_mixin.dart';
 /// Signature for the `listener` function which takes the `BuildContext` along
 /// with the `event` and is responsible for executing in response to
 /// new events.
-typedef BlocPresentationWidgetListener = void Function(
+typedef BlocPresentationWidgetListener<P> = void Function(
   BuildContext context,
-  BlocPresentationEvent event,
+  P event,
 );
 
 /// {@template bloc_presentation_listener}
 /// Widget that listens to new presentation events in a specified [bloc].
 /// {@endtemplate}
-class BlocPresentationListener<B extends BlocPresentationMixin<dynamic>>
+class BlocPresentationListener<B extends BlocPresentationMixin<dynamic, P>, P>
     extends SingleChildStatelessWidget {
   /// {@macro bloc_presentation_listener}
   const BlocPresentationListener({
@@ -34,7 +33,7 @@ class BlocPresentationListener<B extends BlocPresentationMixin<dynamic>>
   final B? bloc;
 
   /// The [BlocPresentationWidgetListener] which will be called on every new presentation event.
-  final BlocPresentationWidgetListener listener;
+  final BlocPresentationWidgetListener<P> listener;
 
   @override
   Widget buildWithChild(BuildContext context, Widget? child) {

packages/bloc_presentation/lib/src/bloc_presentation_mixin.dart

@@ -1,22 +1,19 @@
 import 'dart:async';
 
-import 'package:bloc_presentation/src/bloc_presentation_event.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 
 /// [BlocPresentationMixin] adds a presentation stream to a [BlocBase]
 /// which is automatically disposed.
-mixin BlocPresentationMixin<S> on BlocBase<S> {
-  final _presentationStream =
-      StreamController<BlocPresentationEvent>.broadcast();
+mixin BlocPresentationMixin<S, P> on BlocBase<S> {
+  final _presentationStream = StreamController<P>.broadcast();
 
   /// Stream emitting non-unique presentation events.
-  Stream<BlocPresentationEvent> get presentation => _presentationStream.stream;
+  Stream<P> get presentation => _presentationStream.stream;
 
   /// Emits a new presentation event.
   @protected
-  void emitPresentation(BlocPresentationEvent event) =>
-      _presentationStream.add(event);
+  void emitPresentation(P event) => _presentationStream.add(event);
 
   @override
   @mustCallSuper

packages/bloc_presentation/lib/src/use_bloc_presentation_listener.dart

@@ -6,15 +6,14 @@ import 'package:provider/provider.dart';
 ///
 /// If [bloc] is omitted, [useBlocPresentationListener] will automatically perform
 /// a lookup using [Provider] and the current `BuildContext`.
-void useBlocPresentationListener<B extends BlocPresentationMixin<dynamic>>({
-  required BlocPresentationWidgetListener listener,
+void useBlocPresentationListener<B extends BlocPresentationMixin<dynamic, P>,
+    P>({
+  required BlocPresentationWidgetListener<P> listener,
   B? bloc,
 }) {
   final context = useContext();
   final effectiveStream = bloc?.presentation ??
-      context.select<B, Stream<BlocPresentationEvent>>(
-        (bloc) => bloc.presentation,
-      );
+      context.select<B, Stream<P>>((bloc) => bloc.presentation);
 
   useEffect(
     () {

packages/bloc_presentation/pubspec.yaml

@@ -2,7 +2,7 @@ name: bloc_presentation
 description: >
   Extends blocs with an additional stream which can serve as a way of indicating
   single-time events (so-called "presentation events").
-version: 0.3.0
+version: 0.4.0
 homepage: https://github.com/leancodepl/bloc_presentation/tree/master/packages/bloc_presentation
 
 environment:

packages/bloc_presentation/test/bloc_presentation_mixin_test.dart

@@ -2,22 +2,24 @@ import 'package:bloc_presentation/bloc_presentation.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:flutter_test/flutter_test.dart';
 
-class _TestCubit extends Cubit<int> with BlocPresentationMixin {
+class _TestCubit extends Cubit<int> with BlocPresentationMixin<int, _Event> {
   _TestCubit() : super(0);
 
   void emitValueEvent() => emitPresentation(_ValueEvent());
   void emitReferenceEvent() => emitPresentation(_ReferenceEvent());
 }
 
-class _ValueEvent implements BlocPresentationEvent {
+sealed class _Event {}
+
+class _ValueEvent implements _Event {
   @override
   bool operator ==(Object other) => other is _ValueEvent;
 
   @override
   int get hashCode => 0;
 }
 
-class _ReferenceEvent implements BlocPresentationEvent {}
+class _ReferenceEvent implements _Event {}
 
 void main() {
   group('BlocPresentationMixin', () {

packages/bloc_presentation/test/fakes.dart

@@ -1,14 +1,8 @@
-import 'package:bloc_presentation/bloc_presentation.dart';
 import 'package:flutter/material.dart';
 import 'package:mocktail/mocktail.dart';
 
 class _FakeBuildContext extends Fake implements BuildContext {}
 
-class _FakeBlocPresentationEvent extends Fake implements BlocPresentationEvent {
-  // Flutter 3.3 and 3.7 format this class differently, hence the comment...
-}
-
 void registerFakes() {
   registerFallbackValue(_FakeBuildContext());
-  registerFallbackValue(_FakeBlocPresentationEvent());
 }

packages/bloc_presentation/test/use_bloc_presentation_listener_test.dart

@@ -8,29 +8,33 @@ import 'package:provider/provider.dart';
 
 import 'fakes.dart';
 
-class _TestCubit extends Cubit<int> with BlocPresentationMixin {
+class _TestCubit extends Cubit<int>
+    with BlocPresentationMixin<int, _PresentationEvent> {
   _TestCubit() : super(0);
 
-  void emitEvent(BlocPresentationEvent event) => emitPresentation(event);
+  void emitEvent(_PresentationEvent event) => emitPresentation(event);
 }
 
-class _PresentationEvent implements BlocPresentationEvent {}
+class _PresentationEvent {}
 
 class _MockListener extends Mock {
   void call(
     BuildContext context,
-    BlocPresentationEvent event,
+    _PresentationEvent event,
   );
 }
 
 void main() {
   group('useBlocPresentationListener', () {
     late _TestCubit cubit;
-    late BlocPresentationWidgetListener listener;
-    late BlocPresentationEvent event;
+    late BlocPresentationWidgetListener<_PresentationEvent> listener;
+    late _PresentationEvent event;
     late HookElement element;
 
-    setUpAll(registerFakes);
+    setUpAll(() {
+      registerFakes();
+      registerFallbackValue(_PresentationEvent());
+    });
 
     setUp(() {
       cubit = _TestCubit();
@@ -70,7 +74,9 @@ void main() {
           child: HookBuilder(
             builder: (context) {
               element = context as HookElement;
-              useBlocPresentationListener<_TestCubit>(listener: listener);
+              useBlocPresentationListener<_TestCubit, _PresentationEvent>(
+                listener: listener,
+              );
 
               return Container();
             },
@@ -172,7 +178,7 @@ void main() {
       await tester.pumpWidget(
         HookBuilder(
           builder: (context) {
-            useBlocPresentationListener(
+            useBlocPresentationListener<_TestCubit, _PresentationEvent>(
               listener: listener2,
               bloc: cubit2,
             );