restructured the add to app samples (#698)

add_to_app/books/flutter_module_books/.gitignore

@@ -0,0 +1,48 @@
+.DS_Store
+.dart_tool/
+
+.packages
+.pub/
+
+.idea/
+.vagrant/
+.sconsign.dblite
+.svn/
+
+*.swp
+profile
+
+DerivedData/
+
+.generated/
+
+*.pbxuser
+*.mode1v3
+*.mode2v3
+*.perspectivev3
+
+!default.pbxuser
+!default.mode1v3
+!default.mode2v3
+!default.perspectivev3
+
+xcuserdata
+
+*.moved-aside
+
+*.pyc
+*sync/
+Icon?
+.tags*
+
+build/
+.android/
+.ios/
+.flutter-plugins
+.flutter-plugins-dependencies
+
+# Symbolication related
+app.*.symbols
+
+# Obfuscation related
+app.*.map.json

add_to_app/books/flutter_module_books/.metadata

@@ -0,0 +1,10 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: c0091b289e9966b6da99647b2f18dcb93de1f207
+  channel: master
+
+project_type: module

add_to_app/books/flutter_module_books/README.md

@@ -0,0 +1,50 @@
+# Books add-to-app sample
+
+This application simulates a mock scenario in which an existing app with
+business logic and middleware already exists. It demonstrates how to add Flutter
+to an app that has established patterns for these domains. For more information
+on how to use it, see the [README.md](../README.md) parent directory.
+
+This application also utilizes the [Pigeon](https://pub.dev/packages/pigeon)
+plugin to avoid manual platform channel wiring. Pigeon autogenerates the
+platform channel code in Dart/Java/Objective-C to allow interop using higher
+order functions and data classes instead of string-encoded methods and
+serialized primitives.
+
+The Pigeon autogenerated code is checked-in and ready to use. If the schema
+in `pigeon/schema.dart` is updated, the generated classes can also be re-
+generated using:
+
+```shell
+flutter pub run pigeon \
+    --input pigeon/schema.dart \
+    --java_out ../android_books/app/src/main/java/dev/flutter/example/books/Api.java \
+    --java_package "dev.flutter.example.books"
+```
+
+## Demonstrated concepts
+
+* An existing books catalog app is already implemented in Kotlin and Swift.
+* The platform-side app has existing middleware constraints that should also
+  be the middleware foundation for the additional Flutter screen.
+    * On Android, the Kotlin app already uses GSON and OkHttp for networking and
+      references the Google Books API as a data source. These same libraries
+      also underpin the data fetched and shown in the Flutter screen.
+* The platform application interfaces with the Flutter book details page using
+  idiomatic platform API conventions rather than Flutter conventions.
+    * On Android, the Flutter activity receives the book to show via activity
+      intent and returns the edited book by setting the result intent on the
+      activity. No Flutter concepts are leaked into the consumer activity.
+* The [pigeon](https://pub.dev/packages/pigeon) plugin is used to generate
+  interop APIs and data classes. The same `Book` model class is used within the
+  Kotlin/Swift program, the Dart program and in the interop between Kotlin/Swift
+  and Dart.
+
+## More info
+
+For more information about Flutter, check out
+[flutter.dev](https://flutter.dev).
+
+For instructions on how to integrate Flutter modules into your existing
+applications, see Flutter's
+[add-to-app documentation](https://flutter.dev/docs/development/add-to-app).

add_to_app/books/flutter_module_books/lib/api.dart

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+// Autogenerated from Pigeon (v0.1.0), do not edit directly.
+// See also: https://pub.dev/packages/pigeon
+// ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import
+import 'dart:async';
+import 'package:flutter/services.dart';
+
+class Book {
+  String title;
+  String subtitle;
+  String author;
+  String description;
+  String publishDate;
+  int pageCount;
+  // ignore: unused_element
+  Map<dynamic, dynamic> _toMap() {
+    final Map<dynamic, dynamic> pigeonMap = <dynamic, dynamic>{};
+    pigeonMap['title'] = title;
+    pigeonMap['subtitle'] = subtitle;
+    pigeonMap['author'] = author;
+    pigeonMap['description'] = description;
+    pigeonMap['publishDate'] = publishDate;
+    pigeonMap['pageCount'] = pageCount;
+    return pigeonMap;
+  }
+
+  // ignore: unused_element
+  static Book _fromMap(Map<dynamic, dynamic> pigeonMap) {
+    final Book result = Book();
+    result.title = pigeonMap['title'];
+    result.subtitle = pigeonMap['subtitle'];
+    result.author = pigeonMap['author'];
+    result.description = pigeonMap['description'];
+    result.publishDate = pigeonMap['publishDate'];
+    result.pageCount = pigeonMap['pageCount'];
+    return result;
+  }
+}
+
+abstract class FlutterBookApi {
+  void displayBookDetails(Book arg);
+  static void setup(FlutterBookApi api) {
+    {
+      const BasicMessageChannel<dynamic> channel = BasicMessageChannel<dynamic>(
+          'dev.flutter.pigeon.FlutterBookApi.displayBookDetails',
+          StandardMessageCodec());
+      channel.setMessageHandler((dynamic message) async {
+        final Map<dynamic, dynamic> mapMessage =
+            message as Map<dynamic, dynamic>;
+        final Book input = Book._fromMap(mapMessage);
+        api.displayBookDetails(input);
+      });
+    }
+  }
+}
+
+class HostBookApi {
+  Future<void> cancel() async {
+    const BasicMessageChannel<dynamic> channel = BasicMessageChannel<dynamic>(
+        'dev.flutter.pigeon.HostBookApi.cancel', StandardMessageCodec());
+
+    final Map<dynamic, dynamic> replyMap = await channel.send(null);
+    if (replyMap == null) {
+      throw PlatformException(
+          code: 'channel-error',
+          message: 'Unable to establish connection on channel.',
+          details: null);
+    } else if (replyMap['error'] != null) {
+      final Map<dynamic, dynamic> error = replyMap['error'];
+      throw PlatformException(
+          code: error['code'],
+          message: error['message'],
+          details: error['details']);
+    } else {
+      // noop
+    }
+  }
+
+  Future<void> finishEditingBook(Book arg) async {
+    final Map<dynamic, dynamic> requestMap = arg._toMap();
+    const BasicMessageChannel<dynamic> channel = BasicMessageChannel<dynamic>(
+        'dev.flutter.pigeon.HostBookApi.finishEditingBook',
+        StandardMessageCodec());
+
+    final Map<dynamic, dynamic> replyMap = await channel.send(requestMap);
+    if (replyMap == null) {
+      throw PlatformException(
+          code: 'channel-error',
+          message: 'Unable to establish connection on channel.',
+          details: null);
+    } else if (replyMap['error'] != null) {
+      final Map<dynamic, dynamic> error = replyMap['error'];
+      throw PlatformException(
+          code: error['code'],
+          message: error['message'],
+          details: error['details']);
+    } else {
+      // noop
+    }
+  }
+}

add_to_app/books/flutter_module_books/lib/main.dart

@@ -0,0 +1,201 @@
+// Copyright 2020 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_module_books/api.dart';
+
+void main() => runApp(MyApp());
+
+class MyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      theme: ThemeData(
+        primaryColor: const Color(0xff6200ee),
+      ),
+      home: BookDetail(),
+    );
+  }
+}
+
+typedef BookReceived = void Function(Book book);
+
+class FlutterBookApiHandler extends FlutterBookApi {
+  FlutterBookApiHandler(this.callback);
+
+  final BookReceived callback;
+
+  @override
+  void displayBookDetails(Book book) {
+    assert(
+      book != null,
+      'Non-null book expected from FlutterBookApi.displayBookDetails call.',
+    );
+    callback(book);
+  }
+}
+
+class BookDetail extends StatefulWidget {
+  const BookDetail({this.hostApi, this.flutterApi});
+
+  // These are the outgoing and incoming APIs that are here for injection for
+  // tests.
+  final HostBookApi hostApi;
+  final FlutterBookApi flutterApi;
+
+  @override
+  _BookDetailState createState() => _BookDetailState();
+}
+
+class _BookDetailState extends State<BookDetail> {
+  Book book;
+
+  HostBookApi hostApi;
+
+  FocusNode textFocusNode = FocusNode();
+  TextEditingController titleTextController = TextEditingController();
+  TextEditingController subtitleTextController = TextEditingController();
+  TextEditingController authorTextController = TextEditingController();
+
+  @override
+  void initState() {
+    super.initState();
+
+    // This `HostBookApi` class instance lets us make outgoing calls to the
+    // platform.
+    hostApi = widget.hostApi ?? HostBookApi();
+
+    // Registering this `FlutterBookApiHandler` class lets us receive incoming
+    // calls from the platform.
+    // TODO(gaaclarke): make the setup method an instance method so it's
+    // injectable https://github.com/flutter/flutter/issues/59119.
+    FlutterBookApi.setup(FlutterBookApiHandler(
+        // The `FlutterBookApi` just has one method. Just give a closure for that
+        // method to the handler class.
+        (Book book) {
+      setState(() {
+        // This book model is what we're going to return to Kotlin eventually.
+        // Keep it bound to the UI.
+        this.book = book;
+        titleTextController.text = book.title;
+        titleTextController.addListener(() {
+          this.book?.title = titleTextController.text;
+        });
+        // Subtitle could be null.
+        // TODO(gaaclarke): https://github.com/flutter/flutter/issues/59118.
+        subtitleTextController.text = book.subtitle ?? '';
+        subtitleTextController.addListener(() {
+          this.book?.subtitle = subtitleTextController.text;
+        });
+        authorTextController.text = book.author;
+        authorTextController.addListener(() {
+          this.book?.author = authorTextController.text;
+        });
+      });
+    }));
+  }
+
+  void clear() {
+    book = null;
+    // Keep focus if going to the home screen but unfocus if leaving
+    // the activity.
+    textFocusNode.unfocus();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Book Details'),
+        leading: IconButton(
+          icon: Icon(Icons.clear),
+          // Pressing clear cancels the edit and leaves the activity without
+          // modification.
+          onPressed: () {
+            hostApi.cancel();
+            clear();
+          },
+        ),
+        actions: [
+          IconButton(
+            icon: Icon(Icons.check),
+            // Pressing save sends the updated book to the platform.
+            onPressed: () {
+              hostApi.finishEditingBook(book);
+              clear();
+            },
+          ),
+        ],
+      ),
+      body: book == null
+          // Draw a spinner until the platform gives us the book to show details
+          // for.
+          ? Center(child: CircularProgressIndicator())
+          : Focus(
+              focusNode: textFocusNode,
+              child: ListView(
+                padding: EdgeInsets.all(24),
+                children: [
+                  TextField(
+                    controller: titleTextController,
+                    decoration: InputDecoration(
+                      border: OutlineInputBorder(),
+                      filled: true,
+                      hintText: "Title",
+                      labelText: "Title",
+                    ),
+                  ),
+                  SizedBox(height: 24),
+                  TextField(
+                    controller: subtitleTextController,
+                    maxLines: 2,
+                    decoration: InputDecoration(
+                      border: OutlineInputBorder(),
+                      filled: true,
+                      hintText: "Subtitle",
+                      labelText: "Subtitle",
+                    ),
+                  ),
+                  SizedBox(height: 24),
+                  TextField(
+                    controller: authorTextController,
+                    decoration: InputDecoration(
+                      border: OutlineInputBorder(),
+                      filled: true,
+                      hintText: "Author",
+                      labelText: "Author",
+                    ),
+                  ),
+                  SizedBox(height: 32),
+                  Divider(),
+                  Center(
+                    child: Padding(
+                      padding: const EdgeInsets.all(8.0),
+                      child: Text(
+                          '${book.pageCount} pages  ~  published ${book.publishDate}'),
+                    ),
+                  ),
+                  Divider(),
+                  SizedBox(height: 32),
+                  Center(
+                    child: Text(
+                      'BOOK DESCRIPTION',
+                      style: TextStyle(
+                        fontSize: 15,
+                        fontWeight: FontWeight.bold,
+                        decoration: TextDecoration.underline,
+                      ),
+                    ),
+                  ),
+                  SizedBox(height: 12),
+                  Text(
+                    book.description,
+                    style: TextStyle(color: Colors.grey.shade600, height: 1.24),
+                  ),
+                ],
+              ),
+            ),
+    );
+  }
+}

add_to_app/books/flutter_module_books/pigeon/schema.dart

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+// Copyright 2020 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:pigeon/pigeon.dart';
+
+class Book {
+  String title;
+  String subtitle;
+  String author;
+  String description;
+  String publishDate;
+  int pageCount;
+  // Thumbnail thumbnail;
+}
+
+// TODO(gaaclarke): add this back when the https://github.com/flutter/flutter/issues/58896
+// crash is resolved.
+// class Thumbnail {
+//   String url;
+// }
+
+@FlutterApi()
+abstract class FlutterBookApi {
+  void displayBookDetails(Book book);
+}
+
+@HostApi()
+abstract class HostBookApi {
+  void cancel();
+  void finishEditingBook(Book book);
+}

add_to_app/books/flutter_module_books/pubspec.lock

@@ -0,0 +1,342 @@
+# Generated by pub
+# See https://dart.dev/tools/pub/glossary#lockfile
+packages:
+  _fe_analyzer_shared:
+    dependency: transitive
+    description:
+      name: _fe_analyzer_shared
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "12.0.0"
+  analyzer:
+    dependency: transitive
+    description:
+      name: analyzer
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.40.6"
+  args:
+    dependency: transitive
+    description:
+      name: args
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.6.0"
+  async:
+    dependency: transitive
+    description:
+      name: async
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.5.0-nullsafety.1"
+  boolean_selector:
+    dependency: transitive
+    description:
+      name: boolean_selector
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0-nullsafety.1"
+  build:
+    dependency: transitive
+    description:
+      name: build
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.6.0"
+  built_collection:
+    dependency: transitive
+    description:
+      name: built_collection
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "4.3.2"
+  built_value:
+    dependency: transitive
+    description:
+      name: built_value
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "7.1.0"
+  characters:
+    dependency: transitive
+    description:
+      name: characters
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.0-nullsafety.3"
+  charcode:
+    dependency: transitive
+    description:
+      name: charcode
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0-nullsafety.1"
+  cli_util:
+    dependency: transitive
+    description:
+      name: cli_util
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.2.0"
+  clock:
+    dependency: transitive
+    description:
+      name: clock
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.0-nullsafety.1"
+  code_builder:
+    dependency: transitive
+    description:
+      name: code_builder
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "3.5.0"
+  collection:
+    dependency: transitive
+    description:
+      name: collection
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.15.0-nullsafety.3"
+  convert:
+    dependency: transitive
+    description:
+      name: convert
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.1"
+  crypto:
+    dependency: transitive
+    description:
+      name: crypto
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.5"
+  dart_style:
+    dependency: transitive
+    description:
+      name: dart_style
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.3.10"
+  fake_async:
+    dependency: transitive
+    description:
+      name: fake_async
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0-nullsafety.1"
+  file:
+    dependency: transitive
+    description:
+      name: file
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "5.2.1"
+  fixnum:
+    dependency: transitive
+    description:
+      name: fixnum
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.10.11"
+  flutter:
+    dependency: "direct main"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  flutter_test:
+    dependency: "direct dev"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  glob:
+    dependency: transitive
+    description:
+      name: glob
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0"
+  intl:
+    dependency: transitive
+    description:
+      name: intl
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.16.1"
+  js:
+    dependency: transitive
+    description:
+      name: js
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.6.2"
+  logging:
+    dependency: transitive
+    description:
+      name: logging
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.11.4"
+  matcher:
+    dependency: transitive
+    description:
+      name: matcher
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.12.10-nullsafety.1"
+  meta:
+    dependency: transitive
+    description:
+      name: meta
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.3.0-nullsafety.3"
+  mockito:
+    dependency: "direct dev"
+    description:
+      name: mockito
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "4.1.3"
+  node_interop:
+    dependency: transitive
+    description:
+      name: node_interop
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.1"
+  node_io:
+    dependency: transitive
+    description:
+      name: node_io
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0"
+  package_config:
+    dependency: transitive
+    description:
+      name: package_config
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.9.3"
+  path:
+    dependency: transitive
+    description:
+      name: path
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.8.0-nullsafety.1"
+  pedantic:
+    dependency: transitive
+    description:
+      name: pedantic
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.9.2"
+  pigeon:
+    dependency: "direct dev"
+    description:
+      name: pigeon
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.1.17"
+  pub_semver:
+    dependency: transitive
+    description:
+      name: pub_semver
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.4.4"
+  quiver:
+    dependency: transitive
+    description:
+      name: quiver
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.5"
+  sky_engine:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.99"
+  source_gen:
+    dependency: transitive
+    description:
+      name: source_gen
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.9.10+1"
+  source_span:
+    dependency: transitive
+    description:
+      name: source_span
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.8.0-nullsafety.2"
+  stack_trace:
+    dependency: transitive
+    description:
+      name: stack_trace
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.10.0-nullsafety.1"
+  stream_channel:
+    dependency: transitive
+    description:
+      name: stream_channel
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0-nullsafety.1"
+  string_scanner:
+    dependency: transitive
+    description:
+      name: string_scanner
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.0-nullsafety.1"
+  term_glyph:
+    dependency: transitive
+    description:
+      name: term_glyph
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0-nullsafety.1"
+  test_api:
+    dependency: transitive
+    description:
+      name: test_api
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.2.19-nullsafety.2"
+  typed_data:
+    dependency: transitive
+    description:
+      name: typed_data
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.3.0-nullsafety.3"
+  vector_math:
+    dependency: transitive
+    description:
+      name: vector_math
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0-nullsafety.3"
+  watcher:
+    dependency: transitive
+    description:
+      name: watcher
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.9.7+15"
+  yaml:
+    dependency: transitive
+    description:
+      name: yaml
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.2.1"
+sdks:
+  dart: ">=2.10.0 <2.11.0"

add_to_app/books/flutter_module_books/pubspec.yaml

@@ -0,0 +1,33 @@
+name: flutter_module_books
+description: A Flutter module using the Pigeon package to demonstrate
+  integrating Flutter in a realistic scenario where the existing platform app
+  already has business logic and middleware constraints.
+
+version: 1.0.0+1
+
+environment:
+  sdk: ">=2.7.0 <3.0.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+
+dev_dependencies:
+  pigeon: ^0.1.0
+  mockito: ^4.1.1
+  flutter_test:
+    sdk: flutter
+
+flutter:
+  uses-material-design: true
+
+  # This section identifies your Flutter project as a module meant for
+  # embedding in a native host app.  These identifiers should _not_ ordinarily
+  # be changed after generation - they are used to ensure that the tooling can
+  # maintain consistency when adding or modifying assets and plugins.
+  # They also do not have any bearing on your native host application's
+  # identifiers, which may be completely independent or the same as these.
+  module:
+    androidX: true
+    androidPackage: dev.flutter.example.flutter_module_books
+    iosBundleIdentifier: dev.flutter.example.flutterModuleBooks

add_to_app/books/flutter_module_books/test/widget_test.dart

@@ -0,0 +1,43 @@
+// Copyright 2020 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_module_books/api.dart';
+import 'package:flutter_module_books/main.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mockito/mockito.dart';
+
+void main() {
+  testWidgets('Pressing clear calls the cancel API',
+      (WidgetTester tester) async {
+    MockHostBookApi mockHostApi = MockHostBookApi();
+
+    await tester.pumpWidget(
+      MaterialApp(
+        home: BookDetail(hostApi: mockHostApi),
+      ),
+    );
+
+    await tester.tap(find.byIcon(Icons.clear));
+
+    verify(mockHostApi.cancel());
+  });
+
+  testWidgets('Pressing done calls the finish editing API',
+      (WidgetTester tester) async {
+    MockHostBookApi mockHostApi = MockHostBookApi();
+
+    await tester.pumpWidget(
+      MaterialApp(
+        home: BookDetail(hostApi: mockHostApi),
+      ),
+    );
+
+    await tester.tap(find.byIcon(Icons.check));
+
+    verify(mockHostApi.finishEditingBook(any));
+  });
+}
+
+class MockHostBookApi extends Mock implements HostBookApi {}