Added iOS example for add-to-app Pigeon (#722)

add_to_app/books/flutter_module_books/lib/api.dart

@@ -1,38 +1,42 @@
-// Autogenerated from Pigeon (v0.1.0), do not edit directly.
+// Autogenerated from Pigeon (v0.1.17), 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
+// @dart = 2.8
 import 'dart:async';
+import 'dart:typed_data' show Uint8List, Int32List, Int64List, Float64List;
+
 import 'package:flutter/services.dart';
 
 class Book {
   String title;
   String subtitle;
   String author;
-  String description;
+  String summary;
   String publishDate;
   int pageCount;
+
   // ignore: unused_element
-  Map<dynamic, dynamic> _toMap() {
-    final Map<dynamic, dynamic> pigeonMap = <dynamic, dynamic>{};
+  Object encode() {
+    final Map<Object, Object> pigeonMap = <Object, Object>{};
     pigeonMap['title'] = title;
     pigeonMap['subtitle'] = subtitle;
     pigeonMap['author'] = author;
-    pigeonMap['description'] = description;
+    pigeonMap['summary'] = summary;
     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;
+  static Book decode(Object message) {
+    final Map<Object, Object> pigeonMap = message as Map<Object, Object>;
+    return Book()
+      ..title = pigeonMap['title'] as String
+      ..subtitle = pigeonMap['subtitle'] as String
+      ..author = pigeonMap['author'] as String
+      ..summary = pigeonMap['summary'] as String
+      ..publishDate = pigeonMap['publishDate'] as String
+      ..pageCount = pigeonMap['pageCount'] as int;
   }
 }
 
@@ -40,59 +44,71 @@ abstract class FlutterBookApi {
   void displayBookDetails(Book arg);
   static void setup(FlutterBookApi api) {
     {
-      const BasicMessageChannel<dynamic> channel = BasicMessageChannel<dynamic>(
+      const BasicMessageChannel<Object> channel = BasicMessageChannel<Object>(
           '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);
-      });
+      if (api == null) {
+        channel.setMessageHandler(null);
+      } else {
+        channel.setMessageHandler((Object message) async {
+          if (message == null) {
+            return;
+          }
+          final Book input = Book.decode(message);
+          api.displayBookDetails(input);
+          return;
+        });
+      }
     }
   }
 }
 
 class HostBookApi {
   Future<void> cancel() async {
-    const BasicMessageChannel<dynamic> channel = BasicMessageChannel<dynamic>(
+    const BasicMessageChannel<Object> channel = BasicMessageChannel<Object>(
         'dev.flutter.pigeon.HostBookApi.cancel', StandardMessageCodec());
-
-    final Map<dynamic, dynamic> replyMap = await channel.send(null);
+    final Map<Object, Object> replyMap =
+        await channel.send(null) as Map<Object, Object>;
     if (replyMap == null) {
       throw PlatformException(
-          code: 'channel-error',
-          message: 'Unable to establish connection on channel.',
-          details: null);
+        code: 'channel-error',
+        message: 'Unable to establish connection on channel.',
+        details: null,
+      );
     } else if (replyMap['error'] != null) {
-      final Map<dynamic, dynamic> error = replyMap['error'];
+      final Map<Object, Object> error =
+          replyMap['error'] as Map<Object, Object>;
       throw PlatformException(
-          code: error['code'],
-          message: error['message'],
-          details: error['details']);
+        code: error['code'] as String,
+        message: error['message'] as String,
+        details: error['details'],
+      );
     } else {
       // noop
     }
   }
 
   Future<void> finishEditingBook(Book arg) async {
-    final Map<dynamic, dynamic> requestMap = arg._toMap();
-    const BasicMessageChannel<dynamic> channel = BasicMessageChannel<dynamic>(
+    final Object encoded = arg.encode();
+    const BasicMessageChannel<Object> channel = BasicMessageChannel<Object>(
         'dev.flutter.pigeon.HostBookApi.finishEditingBook',
         StandardMessageCodec());
-
-    final Map<dynamic, dynamic> replyMap = await channel.send(requestMap);
+    final Map<Object, Object> replyMap =
+        await channel.send(encoded) as Map<Object, Object>;
     if (replyMap == null) {
       throw PlatformException(
-          code: 'channel-error',
-          message: 'Unable to establish connection on channel.',
-          details: null);
+        code: 'channel-error',
+        message: 'Unable to establish connection on channel.',
+        details: null,
+      );
     } else if (replyMap['error'] != null) {
-      final Map<dynamic, dynamic> error = replyMap['error'];
+      final Map<Object, Object> error =
+          replyMap['error'] as Map<Object, Object>;
       throw PlatformException(
-          code: error['code'],
-          message: error['message'],
-          details: error['details']);
+        code: error['code'] as String,
+        message: error['message'] as String,
+        details: error['details'],
+      );
     } else {
       // noop
     }

add_to_app/books/flutter_module_books/lib/main.dart

@@ -190,7 +190,7 @@ class _BookDetailState extends State<BookDetail> {
                   ),
                   SizedBox(height: 12),
                   Text(
-                    book.description,
+                    book.summary,
                     style: TextStyle(color: Colors.grey.shade600, height: 1.24),
                   ),
                 ],