[Feature] macOS support

README.md

@@ -275,3 +275,66 @@ public class MainApplication extends FlutterApplication {
   }
 }
 ```
+
+#### MacOS
+
+Due to limmitations on MacOS (see https://github.com/flutter/flutter/issues/65222), you need to put this code in your `lib/main.dart` file
+
+**lib/main.dart**
+```
+@pragma('vm:entry-point')
+void _flutterIsolateEntryPoint() => FlutterIsolate.macosIsolateInitialize();
+```
+
+**You also need to manually fix plugin registration .**
+
+On iOS, Flutter automatically generates a file `GeneratedPluginRegistrant.m` during build that registers all native code plugins during app start. This allows Flutter to find the platform channels.
+
+The generated file looks something like this:
+
+**GeneratedPluginRegistrant.m**
+```
+//
+//  Generated file. Do not edit.
+//
+
+// clang-format off
+
+#import "GeneratedPluginRegistrant.h"
+
+#if __has_include(<flutter_downloader/FlutterDownloaderPlugin.h>)
+#import <flutter_downloader/FlutterDownloaderPlugin.h>
+#else
+@import flutter_downloader;
+#endif
+
+#if __has_include(<path_provider_foundation/PathProviderPlugin.h>)
+#import <path_provider_foundation/PathProviderPlugin.h>
+#else
+@import path_provider_foundation;
+#endif
+
+@implementation GeneratedPluginRegistrant
+
++ (void)registerWithRegistry:(NSObject<FlutterPluginRegistry>*)registry {
+  [FlutterDownloaderPlugin registerWithRegistrar:[registry registrarForPlugin:@"FlutterDownloaderPlugin"]];
+  [PathProviderPlugin registerWithRegistrar:[registry registrarForPlugin:@"PathProviderPlugin"]];
+}
+
+@end
+```
+
+On iOS, this generated file uses Objective-C so `flutter_isolate` can find it using `NSClassFromString(@"GeneratedPluginRegistrant")`.
+
+However, on macOS, this generated file uses Swift & does not use a class, so `NSClassFromString` will not work.
+
+In order to fix plugin registration on MacOS, you need to follow these steps.
+
+1. copy `ios/runner/GeneratedPluginRegistrant.m` from iOS and copy it to `macos/runner/GeneratedPluginRegistrant.m`
+2. copy `ios/runner/GeneratedPluginRegistrant.h` from iOS and copy it to `macos/runner/GeneratedPluginRegistrant.h`
+3. open Xcode, right click on "Runner" -> "Add Files to Runner" and add macos files from steps 1 & 2
+4. delete plugins from `macos/runner/GeneratedPluginRegistrant.m` if they do not support macos
+
+See the example app for a demonstration of this.
+
+

android/src/main/java/com/rmawatson/flutterisolate/FlutterIsolatePlugin.java

@@ -17,6 +17,7 @@
 import io.flutter.FlutterInjector;
 import io.flutter.embedding.engine.FlutterEngine;
 import io.flutter.embedding.engine.dart.DartExecutor;
+import io.flutter.embedding.engine.FlutterEngineGroup;
 import io.flutter.embedding.engine.plugins.FlutterPlugin;
 import io.flutter.plugin.common.BinaryMessenger;
 import io.flutter.plugin.common.EventChannel;
@@ -50,6 +51,7 @@ public class FlutterIsolatePlugin implements FlutterPlugin, MethodCallHandler, S
     private Queue<IsolateHolder> queuedIsolates;
     private Map<String, IsolateHolder> activeIsolates;
     private Context context;
+    private FlutterEngineGroup engineGroup;
 
     private static void registerWithCustomRegistrant(io.flutter.embedding.engine.FlutterEngine flutterEngine) {
         if (registrant == null) return;
@@ -94,6 +96,7 @@ public static void setCustomIsolateRegistrant(Class registrant) {
 
     @Override
     public void onAttachedToEngine(FlutterPluginBinding binding) {
+        engineGroup = new FlutterEngineGroup(binding.getApplicationContext()); 
         setupChannel(binding.getBinaryMessenger(), binding.getApplicationContext());
     }
 
@@ -115,14 +118,13 @@ private void startNextIsolate() {
 
         FlutterInjector.instance().flutterLoader().ensureInitializationComplete(context, null);
 
-        isolate.engine = new FlutterEngine(context);
-
         FlutterCallbackInformation cbInfo = FlutterCallbackInformation.lookupCallbackInformation(isolate.entryPoint);
-        FlutterRunArguments runArgs = new FlutterRunArguments();
 
-        runArgs.bundlePath = FlutterInjector.instance().flutterLoader().findAppBundlePath();
-        runArgs.libraryPath = cbInfo.callbackLibraryPath;
-        runArgs.entrypoint = cbInfo.callbackName;
+        isolate.engine = engineGroup.createAndRunEngine(context, new DartExecutor.DartEntrypoint(
+            FlutterInjector.instance().flutterLoader().findAppBundlePath(),
+            cbInfo.callbackLibraryPath,
+            cbInfo.callbackName
+        ));
 
         isolate.controlChannel = new MethodChannel(isolate.engine.getDartExecutor().getBinaryMessenger(), NAMESPACE + "/control");
         isolate.startupChannel = new EventChannel(isolate.engine.getDartExecutor().getBinaryMessenger(), NAMESPACE + "/event");
@@ -133,9 +135,6 @@ private void startNextIsolate() {
         if (registrant != null) {
             registerWithCustomRegistrant(isolate.engine);
         }
-
-        DartExecutor.DartCallback dartCallback = new DartExecutor.DartCallback(context.getAssets(), runArgs.bundlePath, cbInfo);
-        isolate.engine.getDartExecutor().executeDartCallback(dartCallback);
     }
 
     @Override

example/.metadata

@@ -4,20 +4,35 @@
 # This file should be version controlled and should not be manually edited.
 
 version:
-  revision: "13c049b42ceac219503e0662eaee9b9bb171ac3a"
-  channel: "master"
+  revision: "67457e669f79e9f8d13d7a68fe09775fefbb79f4"
+  channel: "stable"
 
 project_type: app
 
 # Tracks metadata for the flutter migrate command
 migration:
   platforms:
     - platform: root
-      create_revision: 13c049b42ceac219503e0662eaee9b9bb171ac3a
-      base_revision: 13c049b42ceac219503e0662eaee9b9bb171ac3a
+      create_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+      base_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+    - platform: android
+      create_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+      base_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
     - platform: ios
-      create_revision: 13c049b42ceac219503e0662eaee9b9bb171ac3a
-      base_revision: 13c049b42ceac219503e0662eaee9b9bb171ac3a
+      create_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+      base_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+    - platform: linux
+      create_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+      base_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+    - platform: macos
+      create_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+      base_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+    - platform: web
+      create_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+      base_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+    - platform: windows
+      create_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
+      base_revision: 67457e669f79e9f8d13d7a68fe09775fefbb79f4
 
   # User provided section
 

example/analysis_options.yaml

@@ -7,7 +7,7 @@
 
 # The following line activates a set of recommended lints for Flutter apps,
 # packages, and plugins designed to encourage good coding practices.
-include: package:flutter_lints/flutter.yaml
+#include: package:flutter_lints/flutter.yaml
 
 linter:
   # The lint rules applied to this project can be customized in the

example/android/.gitignore

@@ -9,3 +9,5 @@ GeneratedPluginRegistrant.java
 # Remember to never publicly share your keystore.
 # See https://flutter.dev/docs/deployment/android#reference-the-keystore-from-the-app
 key.properties
+**/*.keystore
+**/*.jks

example/android/app/build.gradle

@@ -1,3 +1,9 @@
+plugins {
+    id "com.android.application"
+    id "kotlin-android"
+    id "dev.flutter.flutter-gradle-plugin"
+}
+
 def localProperties = new Properties()
 def localPropertiesFile = rootProject.file('local.properties')
 if (localPropertiesFile.exists()) {
@@ -6,11 +12,6 @@ if (localPropertiesFile.exists()) {
     }
 }
 
-def flutterRoot = localProperties.getProperty('flutter.sdk')
-if (flutterRoot == null) {
-    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
-}
-
 def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
 if (flutterVersionCode == null) {
     flutterVersionCode = '1'
@@ -21,17 +22,31 @@ if (flutterVersionName == null) {
     flutterVersionName = '1.0'
 }
 
-apply plugin: 'com.android.application'
-apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
-
 android {
-    compileSdkVersion 31
+    namespace "com.rmawatson.example"
+    compileSdkVersion flutter.compileSdkVersion
+    ndkVersion flutter.ndkVersion
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    kotlinOptions {
+        jvmTarget = '1.8'
+    }
+
+    sourceSets {
+        main.java.srcDirs += 'src/main/kotlin'
+    }
 
     defaultConfig {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
-        applicationId "com.example.flutterisolateexample"
-        minSdkVersion 19
-        targetSdkVersion 30
+        applicationId "com.rmawatson.example"
+        // You can update the following values to match your application needs.
+        // For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-gradle-build-configuration.
+        minSdkVersion flutter.minSdkVersion
+        targetSdkVersion flutter.targetSdkVersion
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
     }
@@ -48,3 +63,5 @@ android {
 flutter {
     source '../..'
 }
+
+dependencies {}

example/android/app/src/debug/AndroidManifest.xml

@@ -1,6 +1,6 @@
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.flutterisolateexample">
-    <!-- Flutter needs it to communicate with the running application
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- The INTERNET permission is required for development. Specifically,
+         the Flutter tool needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->
     <uses-permission android:name="android.permission.INTERNET"/>

example/android/app/src/main/AndroidManifest.xml

@@ -1,28 +1,31 @@
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.flutterisolateexample">
-
-    <!-- io.flutter.app.FlutterApplication is an android.app.Application that
-         calls FlutterMain.startInitialization(this); in its onCreate method.
-         In most cases you can leave this as-is, but you if you want to provide
-         additional functionality it is fine to subclass or reimplement
-         FlutterApplication and put your custom class here. -->
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
     <application
-        android:name=".MainApplication"
-        android:label="flutter_isolate_example"
+        android:label="example"
+        android:name="${applicationName}"
         android:icon="@mipmap/ic_launcher">
         <activity
             android:name=".MainActivity"
+            android:exported="true"
             android:launchMode="singleTop"
             android:theme="@style/LaunchTheme"
-            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection|fontScale|screenLayout|density"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
             android:hardwareAccelerated="true"
             android:windowSoftInputMode="adjustResize">
+            <!-- Specifies an Android theme to apply to this Activity as soon as
+                 the Android process has started. This theme is visible to the user
+                 while the Flutter UI initializes. After that, this theme continues
+                 to determine the Window background behind the Flutter UI. -->
+            <meta-data
+              android:name="io.flutter.embedding.android.NormalTheme"
+              android:resource="@style/NormalTheme"
+              />
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
         </activity>
-
+        <!-- Don't delete the meta-data below.
+             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
         <meta-data
             android:name="flutterEmbedding"
             android:value="2" />

example/android/app/src/main/kotlin/com/rmawatson/example/MainActivity.kt

@@ -0,0 +1,6 @@
+package com.rmawatson.example
+
+import io.flutter.embedding.android.FlutterActivity
+
+class MainActivity: FlutterActivity() {
+}

example/android/app/src/main/res/values-night/styles.xml

@@ -3,14 +3,14 @@
     <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is on -->
     <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
         <!-- Show a splash screen on the activity. Automatically removed when
-             Flutter draws its first frame -->
+             the Flutter engine draws its first frame -->
         <item name="android:windowBackground">@drawable/launch_background</item>
     </style>
     <!-- Theme applied to the Android Window as soon as the process has started.
          This theme determines the color of the Android Window while your
          Flutter UI initializes, as well as behind your Flutter UI while its
          running.
-         
+
          This Theme is only used starting with V2 of Flutter's Android embedding. -->
     <style name="NormalTheme" parent="@android:style/Theme.Black.NoTitleBar">
         <item name="android:windowBackground">?android:colorBackground</item>

example/android/app/src/main/res/values/styles.xml

@@ -1,8 +1,18 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-    <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is off -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Light.NoTitleBar">
         <!-- Show a splash screen on the activity. Automatically removed when
-             Flutter draws its first frame -->
+             the Flutter engine draws its first frame -->
         <item name="android:windowBackground">@drawable/launch_background</item>
     </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Light.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
+    </style>
 </resources>

example/android/app/src/profile/AndroidManifest.xml

@@ -1,6 +1,6 @@
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.flutterisolateexample">
-    <!-- Flutter needs it to communicate with the running application
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- The INTERNET permission is required for development. Specifically,
+         the Flutter tool needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->
     <uses-permission android:name="android.permission.INTERNET"/>