exemplo_admob_flutter_setstate.dart

AdmobInterstitial interstitialAd;

  @override
  void initState() {
    super.initState();

    interstitialAd = AdmobInterstitial(
      adUnitId: getInterstitialId(),
      listener: (AdmobAdEvent event, Map<String, dynamic> args) {
        if (event == AdmobAdEvent.closed) interstitialAd.load();
        handleEvent(event, args, 'Interstitial');
      },
    );
    interstitialAd.load();
  }

  AdmobBanner getBanner(AdmobBannerSize size) {
    return AdmobBanner(
      adUnitId: getBannerId(),
      adSize: size,
      listener: (AdmobAdEvent event, Map<String, dynamic> args) {
        handleEvent(event, args, 'Banner');
      },
    );
  }

  void showInterstitial() async {
    if (await interstitialAd.isLoaded) {
      interstitialAd.show();
    } else {
      print("Interstitial ainda não foi carregado...");
    }
  }