flutter - Comparing two lists of objects isn't working - flutter

Question

I've two lists of objects that i wanna compare, a and b:
final dia = DateTime(2017, 9, 7, 17, 30);
final ppp = Parcela("1", 225.5, dia, null, 1, false, false);
final ppp2 =Parcela("1", 225, dia.add(const Duration(days: 3)), null, 1, false, false);
final ppp3 =Parcela("1", 225, dia.add(const Duration(days: 3)), null, 1, false, false);
List<Parcela> a = [ppp,ppp2,];
List<Parcela> b = [ppp, ppp3];
Both of them are equal, but when i try to check it with the functions bellow i get false on response:
print(a.every(b.toSet().contains));
print(listEquals(a, b));
I tried also "quiver" and "collection" libraries from pub dev but the result is the same
The Parcela model:
class Parcela {
String id;
double valor;
DateTime dataPagamento;
DateTime dataPago;
int status;
int ref;
Parcela(String id, double valor, DateTime dataPagamento, DateTime dataPago,
int ref, bool pago, bool atraso) {
this.id = id;
this.valor = valor;
this.dataPagamento = dataPagamento;
this.dataPago = this.dataPago;
this.status = _getStatus(pago, atraso);
this.ref = this.ref;
}
int _getStatus(bool pago, bool atraso) {
if (pago) {
if (atraso) {
return 3;
} else {
return 1;
}
} else {
if (atraso) {
return 2;
} else {
return 0;
}
}
}
}
Edit1:
I've tried Dan James suggestion but my class isn't final as his, so i've removed "final" from name attribute:
class Person extends Equatable {
Person(this.name);
String name;
#override
List<Object> get props => [name];
}
the new test vars:
Person p = Person("name");
Person p2 = Person("name2");
Person p3 = Person("tobias");
List<Person> aa = [p, p2];
List<Person> bb = [p, p2..name = "teste"];
List<Person> cc = [p, p3];
but when i test the lists:
var filtered_lst =List.from(aa.where((value) => !bb.contains(value)));
print(filtered_lst);
print(listEquals(aa, bb));
print(listEquals(aa, cc));
the console returns this:
I/flutter (12746): []
I/flutter (12746): true
I/flutter (12746): false

Answer 1

ppp2 does not equal ppp3 because they are two different instances of a class. You could override the '==' operator to check if each field is the same. ie. ppp2.id == ppp3.id.
eg/ (taken from equatable docs but this is vanillar dart)
class Person {
const Person(this.name);
final String name;
#override
bool operator ==(Object other) =>
identical(this, other) ||
other is Person &&
runtimeType == other.runtimeType &&
name == other.name;
#override
int get hashCode => name.hashCode;
}
Or look into the equatable package which does this for you. https://pub.dev/packages/equatable
Straight from the equatable docs:
import 'package:equatable/equatable.dart';
class Person extends Equatable {
const Person(this.name);
final String name;
#override
List<Object> get props => [name];
}

Answer 2

Using the library equatable from Dan James answer:
import 'package:equatable/equatable.dart';
// ignore: must_be_immutable
class Parcela extends Equatable {
String id;
double valor;
DateTime dataPagamento;
DateTime dataPago;
int status;
int ref;
Parcela(String id, double valor, DateTime dataPagamento, DateTime dataPago,
int ref, bool pago, bool atraso) {
this.id = id;
this.valor = valor;
this.dataPagamento = dataPagamento;
this.dataPago = this.dataPago;
this.status = _getStatus(pago, atraso);
this.ref = this.ref;
}
int _getStatus(bool pago, bool atraso) {
if (pago) {
if (atraso) {
return 3;
} else {
return 2;
}
} else {
if (atraso) {
return 1;
} else {
return 0;
}
}
}
#override
List<Object> get props => [id,valor,dataPagamento,];
}
The only way of copying a list that doesn't point to the same memory address:
List<Parcela> copyParcelas(List<Parcela> list) {
List<Parcela> copyList = [];
for (var item in list) {
List<bool> _status = pagoAtraso(item.status);
Parcela betItems = Parcela(item.id, item.valor, item.dataPagamento,
item.dataPago, item.ref, _status[0], _status[1]);
copyList.add(betItems);
}
return copyList;
}
Then the check to return the list items that changed:
List<Parcela> editarParcelas(List<Parcela> parcelas, List<Parcela> original){
return filteredlst = parcelas.toSet().difference(original.toSet()).toList();
}