flutter create --template=plugin permissions_plugin
flutter create -t plugin --platforms android .
flutter pub add jnigen jni_flutter jni

android {
  // ...
  lint {
        disable.add("Instantiatable")
    }
}

import 'dart:io';

import 'package:jnigen/jnigen.dart';

void main(List<String> args) {
  final packageRoot = Platform.script.resolve('../');
  final config = JniGenerator(
    input: Input(
      classes: [
        'android.app.Application',
        'androidx.activity.ComponentActivity',
        'androidx.fragment.app.FragmentActivity',
        'androidx.activity.result.ActivityResult',
        'androidx.core.app.ActivityCompat',
        'androidx.activity.result.ActivityResultCallback',
        'androidx.activity.result.ActivityResultLauncher',
        'androidx.activity.result.contract.ActivityResultContract',
        'android.content.Intent',
        'androidx.core.content.ContextCompat',
        'android.Manifest',
        'android.content.pm.PackageManager'
      ],
      androidSdk: AndroidSdk(addGradleDeps: true, androidExample: Uri.file('example/')),
    ),
    output: Output(
      dart: DartOutput(
        path: packageRoot.resolve('lib/gen/android.g.dart'),
        structure: OutputStructure.singleFile,
      ),
    ),
  );
  config.generate();
}

static final _id_startActivity = _class.staticMethodId(
    r'startActivity',
    r'(Landroid/content/Context;Landroid/content/Intent;Landroid/os/Bundle;)V',
  );

static final _startActivity =
      jni$_.ProtectedJniExtensions.lookup<
            jni$_.NativeFunction<
              jni$_.JThrowablePtr Function(
                jni$_.Pointer<jni$_.Void>,
                jni$_.JMethodIDPtr,
                jni$_.VarArgs<
                  (
                    jni$_.Pointer<jni$_.Void>,
                    jni$_.Pointer<jni$_.Void>,
                    jni$_.Pointer<jni$_.Void>,
                  )
                >,
              )
            >
          >('globalEnv_CallStaticVoidMethod')
          .asFunction<
            jni$_.JThrowablePtr Function(
              jni$_.Pointer<jni$_.Void>,
              jni$_.JMethodIDPtr,
              jni$_.Pointer<jni$_.Void>,
              jni$_.Pointer<jni$_.Void>,
              jni$_.Pointer<jni$_.Void>,
            )
          >();

static void startActivity(
    context$_.Context context,
    intent$_.Intent intent,
    bundle$_.Bundle? bundle,
  ) {
    final _$$classRef = _class.reference;
    final _$context = context.reference;
    final _$intent = intent.reference;
    final _$bundle = bundle?.reference ?? jni$_.jNullReference;
    _startActivity(
      _$$classRef.pointer,
      _id_startActivity.pointer,
      _$context.pointer,
      _$intent.pointer,
      _$bundle.pointer,
    ).check();
  }

import 'package:flutter/foundation.dart';

import 'gen/android.g.dart';
import 'package:jni/jni.dart';
import 'package:jni_flutter/jni_flutter.dart';

class PermissionsPlugin {
  bool checkPermission(JObject context, String permission) {
    // Returns a simple true or false if the permission has been granted
    var result = ContextCompat.checkSelfPermission(
      context as Context,
      permission.toJString(),
    );
    return result == PackageManager.PERMISSION_GRANTED ? true : false;
  }

  int checkAndRequestPermission(
    JObject context,
    String permission,
    Function callback,
  ) {
    // Do I have permission?
    if (ContextCompat.checkSelfPermission(context as Context, permission.toJString()) ==
        PackageManager.PERMISSION_GRANTED) {
      callback();
    } else if (ActivityCompat.shouldShowRequestPermissionRationale(
          androidActivity(PlatformDispatcher.instance.engineId!)! as Activity,
          permission.toJString(),
        ) ==
        true) {
      // Has the user denied the permission before?
      // Give a reason why I need the permission
      print("I should ask for permission");
      // TODO Flow to show UI to reshow perms dialog
      return -2;
    } else {
      // Ask for permission
      ActivityCompat.requestPermissions(
        androidActivity(PlatformDispatcher.instance.engineId!)! as Activity,
        JArray.of(JString.type, [permission.toJString()]),
        0,
      );
    }
    return 0;
  }
}

flutter:
  # This section identifies this Flutter project as a plugin project.
  # The 'pluginClass' specifies the class (in Java, Kotlin, Swift, Objective-C, etc.)
  # which should be registered in the plugin registry. This is required for
  # using method channels.
  # The Android 'package' specifies package in which the registered class is.
  # This is required for using method channels on Android.
  # The 'ffiPlugin' specifies that native code should be built and bundled.
  # This is required for using `dart:ffi`.
  # All these are used by the tooling to maintain consistency when
  # adding or updating assets for this project.
  plugin:
    platforms:
      android:
        package: com.example.permissions_plugin
        pluginClass: PermissionsPlugin

// A simplified implementation of the main UI to demonstrate the JNI integration.
// Full implementation available in the repository.
class _MyAppState extends State<MyApp> {
  final _permissionsPlugin = PermissionsPlugin();
  bool _isGranted = false;
  String _lastActionStatus = 'Waiting...';

  void _checkPermissionStatus() {
    try {
      // Direct call to JNI-backed logic
      _isGranted = _permissionsPlugin.checkPermission(
        androidApplicationContext,
        "android.permission.CAMERA",
      );
      setState(() => _lastActionStatus = 'Checked: ${_isGranted}');
    } catch (e) {
      setState(() => _lastActionStatus = 'Error: $e');
    }
  }

  void _checkAndRequest() {
    try {
      _permissionsPlugin.checkAndRequestPermission(
        androidApplicationContext,
        "android.permission.CAMERA",
        () => setState(() => _isGranted = true),
      );
      setState(() => _lastActionStatus = 'Invoked check & request');
    } catch (e) {
      setState(() => _lastActionStatus = 'Error: $e');
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Permissions (JNIGEN)')),
      body: Column(
        children: [
          Text("Status: ${_isGranted ? 'Granted' : 'Denied'}"),
          _lastActionStatus,
          ElevatedButton(onPressed: _checkAndRequest, child: const Text("Check & Request")),
          TextButton(onPressed: _checkPermissionStatus, child: const Text("Re-check Status")),
        ],
      ),
    );
  }
}

<manifest xmlns:android="http://schemas.android.com/apk/res/android">
 <uses-permission android:name="android.permission.CAMERA" />
 <application ... ></application>
 /* ...*/

rm -rf lib/permissions_plugin_platform_interface.dart lib/permissions_plugin_method_channel.dart test/permissions_plugin_test.dart test/permissions_plugins_method_channel_test.dart example/integration_test/plugin_integration_test.dart android/src/test/kotlin/com/example/permissions_plugin/PermissionsPluginTest.dart