android – The getter ‘duration’ isn’t defined for the class ‘_MealItemState’

I’m a beginner in flutter I have made some changes by adding createState() and admobe to the original file but I have been stuck in this error: lib/widgets/meal_item.dart:179:33: Error: The getter ‘duration’ isn’t defined for the class ‘_MealItemState’. – ‘_MealItemState’ is from ‘package:oumwalidmaindishes/widgets/meal_item.dart’ (‘lib/widgets/meal_item.dart’). Try correcting the name to the name of an existing getter, … Read more