Add jni

.github/workflows/test-package.yml

@@ -74,6 +74,35 @@ jobs:
           github-token: ${{ secrets.GITHUB_TOKEN }}
           path-to-lcov: ./jni_gen/coverage/lcov.info
 
+  test_jni:
+    runs-on: ${{ matrix.os }}
+    defaults:
+      run:
+        working-directory: ./jni
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest]
+    steps:
+      - uses: actions/checkout@v3
+      - uses: subosito/flutter-action@v2
+        with:
+          channel: 'stable'
+      - uses: actions/setup-java@v2
+        with:
+          distribution: 'zulu'
+          java-version: '11'
+      - run: |
+          mkdir build
+          cd build
+          cmake .. && cmake --build .
+        working-directory: ./jni/src
+      - run: flutter pub get
+      - run: flutter format --output=none --set-exit-if-changed .
+      - run: flutter analyze --fatal-infos
+      - run: dart pub get
+      - run: dart test
+
   build_jni_example_linux:
     runs-on: ubuntu-latest
     defaults:
@@ -84,11 +113,23 @@ jobs:
       - uses: subosito/flutter-action@v2
         with:
           channel: 'stable'
+      - uses: actions/setup-java@v2
+        with:
+          distribution: 'zulu'
+          java-version: '11'
       - run: |
           sudo apt-get update -y
           sudo apt-get install -y ninja-build libgtk-3-dev
+      - run: |
+          cd ../src/
+          mkdir build
+          cd build
+          cmake .. && cmake --build .
+          cd ../../example
       - run: flutter config --enable-linux-desktop
       - run: flutter pub get
+      - run: flutter test
+      - run: flutter test integration_test/integration_test.dart -d linux
       - run: flutter build linux
 
   build_jni_example_windows:
@@ -101,8 +142,13 @@ jobs:
       - uses: subosito/flutter-action@v2
         with:
           channel: 'stable'
+      - uses: actions/setup-java@v2
+        with:
+          distribution: 'zulu'
+          java-version: '11'
       - run: flutter config --enable-windows-desktop
       - run: flutter pub get
+      - run: flutter test integration_test/integration_test.dart -d windows
       - run: flutter build windows
 
   build_jni_example_macos:
@@ -116,6 +162,10 @@ jobs:
         with:
           channel: 'stable'
           architecture: x64
+      - uses: actions/setup-java@v2
+        with:
+          distribution: 'zulu'
+          java-version: '11'
       - run: flutter config --enable-macos-desktop
       - run: flutter pub get
       - run: flutter build macos

jni/android/src/main/java/dev/dart/jni/JniPlugin.java

@@ -0,0 +1,61 @@
+package dev.dart.jni;
+
+import androidx.annotation.Keep;
+import androidx.annotation.NonNull;
+import android.util.Log;
+import android.app.Activity;
+import io.flutter.plugin.common.PluginRegistry.Registrar;
+import io.flutter.embedding.engine.plugins.FlutterPlugin;
+import io.flutter.embedding.engine.plugins.activity.ActivityAware;
+import io.flutter.embedding.engine.plugins.activity.ActivityPluginBinding;
+
+import android.content.Context;
+
+@Keep
+public class JniPlugin implements FlutterPlugin, ActivityAware {
+
+  @Override
+  public void
+  onAttachedToEngine(@NonNull FlutterPluginBinding binding) {
+	  setup(binding.getApplicationContext());
+  }
+
+  public static void registerWith(Registrar registrar) {
+    JniPlugin plugin = new JniPlugin();
+	plugin.setup(registrar.activeContext());
+  }
+
+  private void setup(Context context) {
+	initializeJni(context, getClass().getClassLoader());
+  }
+
+  @Override
+  public void onDetachedFromEngine(@NonNull FlutterPluginBinding binding) {}
+
+  // Activity handling methods
+  @Override
+  public void onAttachedToActivity(@NonNull ActivityPluginBinding binding) {
+	Activity activity = binding.getActivity();
+	setJniActivity(activity, activity.getApplicationContext());
+  }
+
+  @Override
+  public void onDetachedFromActivityForConfigChanges() {}
+
+  @Override
+  public void onReattachedToActivityForConfigChanges(@NonNull ActivityPluginBinding binding) {
+	Activity activity = binding.getActivity();
+	setJniActivity(activity, activity.getApplicationContext());
+  }
+
+  @Override
+  public void onDetachedFromActivity() {}
+
+  native void initializeJni(Context context, ClassLoader classLoader);
+  native void setJniActivity(Activity activity, Context context);
+
+  static {
+	System.loadLibrary("dartjni");
+  }
+}
+

jni/example/android/app/src/main/java/dev/dart/jni_example/AnyToast.java

@@ -0,0 +1,28 @@
+package dev.dart.jni_example;
+
+import android.app.Activity;
+import android.os.Handler;
+import android.content.Context;
+import android.widget.Toast;
+import androidx.annotation.Keep;
+
+@Keep
+class AnyToast {
+	static AnyToast makeText(Activity mainActivity, Context context, CharSequence text, int duration) {
+		AnyToast toast = new AnyToast();
+		toast.mainActivity = mainActivity;
+		toast.context = context;
+		toast.text = text;
+		toast.duration = duration;
+		return toast;
+	}
+
+	void show() {
+		mainActivity.runOnUiThread(() -> Toast.makeText(context, text, duration).show());
+	}
+
+	Activity mainActivity;
+	Context context;
+	CharSequence text;
+	int duration;
+}

jni/example/integration_test/integration_test.dart

@@ -0,0 +1,39 @@
+import 'dart:io';
+// import 'package:path/path.dart' as path;
+import 'package:ffi/ffi.dart';
+
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:jni/jni.dart';
+
+void main() {
+  if (!Platform.isAndroid) {
+    Jni.spawn();
+  }
+
+  var jni = Jni.getInstance();
+
+  testWidgets('Manually lookup & call Long.toHexString static method',
+      (tester) async {
+    final arena = Arena();
+    final env = jni.getEnv();
+
+    final longClass = env.FindClass("java/lang/Long".toNativeChars(arena));
+    final hexMethod = env.GetStaticMethodID(
+        longClass,
+        "toHexString".toNativeChars(arena),
+        "(J)Ljava/lang/String;".toNativeChars(arena));
+
+    for (var i in [1, 80, 13, 76, 1134453224145]) {
+      final jres = env.CallStaticObjectMethodA(
+          longClass, hexMethod, Jni.jvalues([JValueLong(i)], allocator: arena));
+
+      final res = env.asDartString(jres);
+      expect(res, equals(i.toRadixString(16)));
+
+      env.DeleteLocalRef(jres);
+    }
+    env.DeleteLocalRef(longClass);
+    arena.releaseAll();
+  });
+}