interstitialIsLoad method
Implementation
@override
Future<bool?> interstitialIsLoad(String unitId) async {
  final result = await methodChannel.invokeMethod<bool>(
      'interstitialIsLoad', <String, dynamic>{"unitId": unitId});
  return result;
}@override
Future<bool?> interstitialIsLoad(String unitId) async {
  final result = await methodChannel.invokeMethod<bool>(
      'interstitialIsLoad', <String, dynamic>{"unitId": unitId});
  return result;
}