This is a larger change with a goal of no runtime changes for current customers, but in the future Observable will become a very lightweight interface, i.e.:

abstract class Observable<C extends ChangeRecord> {
  Stream<List<C>> get changes;
  • Started deprecating the wide Observable interface
    • ChangeNotifier should be used as a base class for these methods:
      • Observable.observed
      • Observable.unobserved
      • Observable.hasObservers
      • Observable.deliverChanges
      • Observable.notifyChange
    • PropertyChangeNotifier should be used for these methods:
      • Observable.notifyPropertyChange
    • Temporarily, Observable uses ChangeNotifier
      • Existing users of anything but implements Observable should move to implementing or extending ChangeNotifier. In a future release Observable will reduce API surface down to an abstract Stream<List<C>> get changes.
  • Added the ChangeNotifier and PropertyChangeNotifier classes
    • Can be used to implement Observable in a generic manner
  • Observable is now Observable<C extends ChangeRecord>
    • When passing a generic type C, notifyPropertyChange is illegal


  • Refactored MapChangeRecord
    • Added equality and hashCode checks
    • Added MapChangeRecord.apply to apply a change record
  • Added MapDiffer, which implements Differ for a Map


  • Fix a bug in ListDiffer that caused a RangeError


  • Fix analysis errors caused via missing /*<E>*/ syntax in 0.15.0


  • Added the Differ interface, as well as EqualityDiffer
  • Refactored list diffing into a ListDiffer
  • Added concept of ChangeRecord.ANY and ChangeRecord.NONE
    • Low-GC ways to expression “something/nothing” changed
  • Refactored ListChangeRecord
    • Added named constructors for common use cases
    • Added equality and hashCode checks
    • Added ListChangeRecord.apply to apply a change record
  • Added missing @override annotations to satisfy annotate_overrides


  • Add a missing dependency on pkg/meta.