AdMob in Flutter Example

main.dart

import 'package:flutter/material.dart';
import 'package:ads/ads.dart';

// You can also test with your own ad unit IDs by registering your device as a
// test device. Check the logs for your device's ID value.
const String testDevice = 'Samsung_Galaxy_SII_API_26:5554';

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => new _MyAppState();
}

class _MyAppState extends State<MyApp> {

  int _coins = 0;

  @override
  void initState() {
    super.initState();
    Ads.init('ca-app-pub-3940256099942544', testing: true);
    
    Ads.video.rewardedListener = (String rewardType, int rewardAmount){
      setState(() {
         _coins += rewardAmount;
      });
    };

    Ads.showBannerAd(this);
  }

  @override
  void dispose() {
    Ads.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      home: new Scaffold(
        appBar: new AppBar(
          title: const Text('AdMob Plugin example app'),
        ),
        body: new SingleChildScrollView(
          child: new Center(
            child: new Column(
              crossAxisAlignment: CrossAxisAlignment.center,
              mainAxisSize: MainAxisSize.min,
              children: <Widget>[
                new RaisedButton(
                    child: const Text('SHOW BANNER'),
                    onPressed: () {
                        Ads.showBannerAd(this);
                    }),
                new RaisedButton(
                    child: const Text('REMOVE BANNER'),
                    onPressed: () {
                      Ads.hideBannerAd();
                    }),
                new RaisedButton(
                  child: const Text('SHOW INTERSTITIAL'),
                  onPressed: () {
                    Ads.showFullScreenAd(this);
                  },
                ),
                new RaisedButton(
                  child: const Text('SHOW REWARDED VIDEO'),
                  onPressed: () {
                    Ads.showVideoAd(this);
                  },
                ),
                new Text("You have $_coins coins."),
              ].map((Widget button) {
                return new Padding(
                  padding: const EdgeInsets.symmetric(vertical: 16.0),
                  child: button,
                );
              }).toList(),
            ),
          ),
        ),
      ),
    );
  }
}

void main() {
  runApp(new MyApp());
}