operator == method Null safety
- Object o
The equality operator.
The default behavior for all Objects is to return true if and
only if this object and other
are the same object.
Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:
-
Total: It must return a boolean for all arguments. It should never throw.
-
Reflexive: For all objects
o
,o == o
must be true. -
Symmetric: For all objects
o1
ando2
,o1 == o2
ando2 == o1
must either both be true, or both be false. -
Transitive: For all objects
o1
,o2
, ando3
, ifo1 == o2
ando2 == o3
are true, theno1 == o3
must be true.
The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.
If a subclass overrides the equality operator, it should override the hashCode method as well to maintain consistency.
Implementation
@override
bool operator ==(Object o) =>
o is Contact &&
o.id == id &&
o.displayName == displayName &&
o.thumbnail == thumbnail &&
o.photo == photo &&
o.name == name &&
_listEqual(o.phones, phones) &&
_listEqual(o.emails, emails) &&
_listEqual(o.addresses, addresses) &&
_listEqual(o.organizations, organizations) &&
_listEqual(o.websites, websites) &&
_listEqual(o.socialMedias, socialMedias) &&
_listEqual(o.events, events) &&
_listEqual(o.notes, notes);