MainActivity.java

// Copyright 2021 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.YOUR_PACKAGE_NAME;

import io.flutter.embedding.android.FlutterActivity;
import io.flutter.embedding.engine.FlutterEngine;
import io.flutter.plugins.googlemobileads.GoogleMobileAdsPlugin;
import io.flutter.plugins.googlemobileads.GoogleMobileAdsPlugin.NativeAdFactory;

public class MainActivity extends FlutterActivity {
    @Override
    public void configureFlutterEngine(FlutterEngine flutterEngine) {
        super.configureFlutterEngine(flutterEngine);
        final NativeAdFactory factory = new NativeAdFactoryExample(getLayoutInflater());
        GoogleMobileAdsPlugin.registerNativeAdFactory(flutterEngine, "adFactoryExample", factory);
    }

    @Override
    public void cleanUpFlutterEngine(FlutterEngine flutterEngine) {
        GoogleMobileAdsPlugin.unregisterNativeAdFactory(flutterEngine, "adFactoryExample");
    }
}