@Override
public boolean onStartJob(JobParameters params) {
    PersistableBundle extras = params.getExtras();
    Context context = getApplicationContext();
    if (isApplicationRunning(context)) {
        if (callbackMethodChannel != null) {
            callbackMethodChannel.invokeMethod("firedWhileApplicationRunning", null);
        }
    } else {
        FlutterNativeView nativeView = new FlutterNativeView(context);
        if (AndroidJobScheduler.pluginRegistrantCallback != null) {
            AndroidJobScheduler.pluginRegistrantCallback.registerWith(nativeView.getPluginRegistry());
        }
        nativeView.runFromBundle(FlutterMain.findAppBundlePath(context), null,
                extras.getString(B_KEY_DART_CB), true);
    }
    if (!extras.containsKey(B_KEY_SCHEDULE_ONCE)) {
        AndroidJobScheduler.scheduleEvery(getApplicationContext(), AndroidJobSchedulerUtils.persistableBundleToJobInfo(extras));
    }
    jobFinished(params, false);
    return true;
}
 

private void startNextIsolate() {

        IsolateHolder isolate = queuedIsolates.peek();

        FlutterMain.ensureInitializationComplete(context, null);

        if (flutterPluginBinding == null)
            isolate.view = new FlutterNativeView(context, true);
        else
            isolate.engine = new FlutterEngine(context);


        FlutterCallbackInformation cbInfo = FlutterCallbackInformation.lookupCallbackInformation(isolate.entryPoint);
        FlutterRunArguments runArgs = new FlutterRunArguments();

        runArgs.bundlePath = FlutterMain.findAppBundlePath(context);
        runArgs.libraryPath = cbInfo.callbackLibraryPath;
        runArgs.entrypoint = cbInfo.callbackName;

        if (flutterPluginBinding == null) {
            isolate.controlChannel = new MethodChannel(isolate.view, NAMESPACE + "/control");
            isolate.startupChannel = new EventChannel(isolate.view, NAMESPACE + "/event");
        } else {
            isolate.controlChannel = new MethodChannel(isolate.engine.getDartExecutor().getBinaryMessenger(), NAMESPACE + "/control");
            isolate.startupChannel = new EventChannel(isolate.engine.getDartExecutor().getBinaryMessenger(), NAMESPACE + "/event");
        }
        isolate.startupChannel.setStreamHandler(this);
        isolate.controlChannel.setMethodCallHandler(this);
        if (flutterPluginBinding == null) {
            registerWithRegistrant(isolate.view.getPluginRegistry());
            isolate.view.runFromBundle(runArgs);
        } else {
            DartExecutor.DartCallback dartCallback = new DartExecutor.DartCallback(context.getAssets(), runArgs.bundlePath, cbInfo);
            isolate.engine.getDartExecutor().executeDartCallback(dartCallback);
        }
    }
 

private AudioQueryDelegate(final PluginRegistry.Registrar registrar){

        m_artistLoader = new ArtistLoader(registrar.context() );
        m_albumLoader = new AlbumLoader(registrar.context() );
        m_songLoader = new SongLoader( registrar.context() );
        m_genreLoader = new GenreLoader( registrar.context() );
        m_playlistLoader = new PlaylistLoader( registrar.context() );

        m_permissionManager = new PermissionManager() {
            @Override
            public boolean isPermissionGranted(String permissionName) {

                return (ActivityCompat.checkSelfPermission( registrar.activity(), permissionName)
                    == PackageManager.PERMISSION_GRANTED);
            }

            @Override
            public void askForPermission(String permissionName, int requestCode) {
                ActivityCompat.requestPermissions(registrar.activity(), new String[] {permissionName}, requestCode);
            }
        };

        registrar.addRequestPermissionsResultListener(this);
        registrar.addViewDestroyListener(new PluginRegistry.ViewDestroyListener() {
            @Override
            public boolean onViewDestroy(FlutterNativeView flutterNativeView) {
                // ideal
                Log.i("MDBG", "onViewDestroy");
                return true;
            }
        });
    }
 

/**
 * Plugin registration.
 */
public static void registerWith(Registrar registrar) {
    if (registrar.activity() == null) {
        // When a background flutter view tries to register the plugin, the registrar has no activity.
        // We stop the registration process as this plugin is foreground only.
        return;
    }
    final MethodChannel channel = new MethodChannel(registrar.messenger(), "wifi_iot");
    final EventChannel eventChannel = new EventChannel(registrar.messenger(), "plugins.wififlutter.io/wifi_scan");
    final WifiIotPlugin wifiIotPlugin = new WifiIotPlugin(registrar.activity());
    eventChannel.setStreamHandler(wifiIotPlugin);
    channel.setMethodCallHandler(wifiIotPlugin);

    registrar.addViewDestroyListener(new ViewDestroyListener() {
        @Override
        public boolean onViewDestroy(FlutterNativeView view) {
            if (!wifiIotPlugin.ssidsToBeRemovedOnExit.isEmpty()) {
                List<WifiConfiguration> wifiConfigList =
                        wifiIotPlugin.moWiFi.getConfiguredNetworks();
                for (String ssid : wifiIotPlugin.ssidsToBeRemovedOnExit) {
                    for (WifiConfiguration wifiConfig : wifiConfigList) {
                        if (wifiConfig.SSID.equals(ssid)) {
                            wifiIotPlugin.moWiFi.removeNetwork(wifiConfig.networkId);
                        }
                    }
                }
            }
            return false;
        }
    });
}
 

@Override
public boolean onViewDestroy(FlutterNativeView flutterNativeView) {
  Log.i(TAG,"onview destroy called");
  unBoundService();
  return false;
}
 

public XFlutterView(Context context, AttributeSet attrs, FlutterNativeView nativeView){
    super(context,attrs,nativeView);
}
 

@Override
public boolean onViewDestroy(FlutterNativeView flutterNativeView) {
    asyncWork.stop();
    return true;
}
 

public XFlutterView(Context context, AttributeSet attrs, FlutterNativeView nativeView){
    super(context,attrs,nativeView);
}
 

/**
 * Creates a {@link FlutterView} linked to the specified {@link Activity} and {@link Lifecycle}.
 * The optional initial route string will be made available to the Dart code (via
 * {@code window.defaultRouteName}) and may be used to determine which widget should be displayed
 * in the view. The default initialRoute is "/".
 *
 * @param activity an {@link Activity}
 * @param lifecycle a {@link Lifecycle}
 * @param initialRoute an initial route {@link String}, or null
 * @return a {@link FlutterView}
 */
@NonNull
public static FlutterView createView(@NonNull final Activity activity, @NonNull final Lifecycle lifecycle, final String initialRoute) {
  FlutterMain.startInitialization(activity.getApplicationContext());
  FlutterMain.ensureInitializationComplete(activity.getApplicationContext(), null);
  final FlutterNativeView nativeView = new FlutterNativeView(activity);
  final FlutterView flutterView = new FlutterView(activity, null, nativeView) {
    private final BasicMessageChannel<String> lifecycleMessages = new BasicMessageChannel<>(this, "flutter/lifecycle", StringCodec.INSTANCE);
    @Override
    public void onFirstFrame() {
      super.onFirstFrame();
      setAlpha(1.0f);
    }

    @Override
    public void onPostResume() {
      // Overriding default behavior to avoid dictating system UI via PlatformPlugin.
      lifecycleMessages.send("AppLifecycleState.resumed");
    }
  };
  if (initialRoute != null) {
    flutterView.setInitialRoute(initialRoute);
  }
  lifecycle.addObserver(new LifecycleObserver() {
    @OnLifecycleEvent(Lifecycle.Event.ON_CREATE)
    public void onCreate() {
      final FlutterRunArguments arguments = new FlutterRunArguments();
      arguments.bundlePath = FlutterMain.findAppBundlePath(activity.getApplicationContext());
      arguments.entrypoint = "main";
      flutterView.runFromBundle(arguments);
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    public void onStart() {
      flutterView.onStart();
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_RESUME)
    public void onResume() {
      flutterView.onPostResume();
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_PAUSE)
    public void onPause() {
      flutterView.onPause();
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    public void onStop() {
      flutterView.onStop();
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
    public void onDestroy() {
      flutterView.destroy();
    }
  });
  flutterView.setAlpha(0.0f);
  return flutterView;
}
 

/**
 * Creates a {@link FlutterView} linked to the specified {@link Activity} and {@link Lifecycle}.
 * The optional initial route string will be made available to the Dart code (via
 * {@code window.defaultRouteName}) and may be used to determine which widget should be displayed
 * in the view. The default initialRoute is "/".
 *
 * @param activity an {@link Activity}
 * @param lifecycle a {@link Lifecycle}
 * @param initialRoute an initial route {@link String}, or null
 * @return a {@link FlutterView}
 */
@NonNull
public static FlutterView createView(@NonNull final Activity activity, @NonNull final Lifecycle lifecycle, final String initialRoute) {
  FlutterMain.startInitialization(activity.getApplicationContext());
  FlutterMain.ensureInitializationComplete(activity.getApplicationContext(), null);
  final FlutterNativeView nativeView = new FlutterNativeView(activity);
  final FlutterView flutterView = new FlutterView(activity, null, nativeView) {
    private final BasicMessageChannel<String> lifecycleMessages = new BasicMessageChannel<>(this, "flutter/lifecycle", StringCodec.INSTANCE);
    @Override
    public void onFirstFrame() {
      super.onFirstFrame();
      setAlpha(1.0f);
    }

    @Override
    public void onPostResume() {
      // Overriding default behavior to avoid dictating system UI via PlatformPlugin.
      lifecycleMessages.send("AppLifecycleState.resumed");
    }
  };
  if (initialRoute != null) {
    flutterView.setInitialRoute(initialRoute);
  }
  lifecycle.addObserver(new LifecycleObserver() {
    @OnLifecycleEvent(Lifecycle.Event.ON_CREATE)
    public void onCreate() {
      final FlutterRunArguments arguments = new FlutterRunArguments();
      arguments.bundlePath = FlutterMain.findAppBundlePath(activity.getApplicationContext());
      arguments.entrypoint = "main";
      flutterView.runFromBundle(arguments);
      GeneratedPluginRegistrant.registerWith(flutterView.getPluginRegistry());
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    public void onStart() {
      flutterView.onStart();
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_RESUME)
    public void onResume() {
      flutterView.onPostResume();
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_PAUSE)
    public void onPause() {
      flutterView.onPause();
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    public void onStop() {
      flutterView.onStop();
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
    public void onDestroy() {
      flutterView.destroy();
    }
  });
  flutterView.setAlpha(0.0f);
  return flutterView;
}
 

public FlutterNativeView createFlutterNativeView() {
    return null;
}
 

FlutterNativeView createFlutterNativeView(); 

FlutterNativeView createFlutterNativeView();