My AdListener is displaying some error lines in the code

Question

final AdListener listener = AdListener(
    onAdloaded: (ad) {
      print('ad loaded');
    },
    onAdFailedToLoad: (ad, error) {
      ad.dispose();
    },
);

the adlistener on this code is not working

Solution

final BannerAdListener listener = BannerAdListener(
    onAdLoaded: (ad) {
      print('ad loaded');
    },
    onAdFailedToLoad: (ad, error) {
      ad.dispose();
    },
  );

You need to specify which ad format you're using at the function.