retainAll method
Removes all elements of this Watcher's value that are not elements in elements
.
Checks for each element of elements
whether there is an element in this
set that is equal to it (according to this.contains
), and if so, the
equal element in this Watcher's value is retained, and elements that are not equal
to any element in elements
are removed.
final charactersWatcher = <String>{'A', 'B', 'C'}.watcher;
characters.retainAll({'A', 'B', 'X'});
print(characters); // {A, B}
Implementation
@override
void retainAll(Iterable<Object?> elements) =>
updateOnAction(() => value.retainAll(elements));