I have tried to calculate the age of a pet in years, months and days, from the date of birth which the user inputs for my application. However, when I am trying to output the results, it is giving me "Instance of 'PetsAge'" instead of the actual calculated output.

Here is my code:

class PetsAge {
  int years;
  int months;
  int days;
  PetsAge({ this.years = 0, this.months = 0, this.days = 0 });
}

 class PetDetailView extends StatelessWidget {
  final Pet pet;

  PetDetailView({Key key, @required this.pet}) : super(key: key);

PetsAge getPetsAge(String birthday) {
    if (birthday != '') {
      var birthDate = DateTime.tryParse(birthday);
      if (birthDate != null) {
        final now = new DateTime.now();

        int years = now.year - birthDate.year;
        int months = now.month - birthDate.month;
        int days = now.day - birthDate.day;

        if (months < 0 || (months == 0 && days < 0)) {
          years--;
          months  = (days < 0 ? 11 : 12);
        }

        if (days < 0) {
          final monthAgo = new DateTime(now.year, now.month - 1, birthDate.day);
          days = now
              .difference(monthAgo)
              .inDays   1;
        }

        return PetsAge(years: years, months: months, days: days);
      } else {
        print('getTheKidsAge: not a valid date');
      }
    } else {
      print('getTheKidsAge: date is empty');
    }
    return PetsAge();
  }
}

This is how I called it in a Card:

Widget petsAgeCard() {
    return Card(
      child: Column(
        mainAxisSize: MainAxisSize.min,
        children: <Widget>[
          ListTile(
            leading: Image(
              image: AssetImage("Assets/images/age.png"),
            ),
            title: Text(
              "Your Pet's Age",
              style: TextStyle(
                  fontSize: 30, fontWeight: FontWeight.w500
              ),
            ),
            subtitle: Text("${getPetsAge(pet.dob.year.toString())}"),
          ),
        ],
      ),
    );
  }

CodePudding user response：

This is the expected behavior because you return a PetsAge object. You can directly return a String from your getPetsAge method instead of the object.

OR, you can override the toString method of your object and return the age only but i think it is not a good idea to do like this.