Skipping certain Scenes/Navigators when saving state about acorn HOT 1 CLOSED

Since most of the base implementations implement Savable* to allow easy state saving, this doesn't really allow intentionally not supporting state saving: the easiest of checks is whether the component implements Savable* and then actually calling saveInstanceState() on it.

Two solutions come to mind:

• Include a property isStateSavable to the Savable* interfaces to indicate whether an implementation actually supports state saving. The interfaces can return true by default. This leads to some contradictive semantics though: A SavableScene that returns false for isStateSavable doesn't really make sense.

• Don't let the base implementations actually implement Savable*, but do provide the saveInstanceState() implementation without overriding. Implementing classes can then just slap a Savable* on their class definition without having to override saveInstanceState():

abstract class StackNavigator(...) :  Navigator {
  /* ... */
  open fun saveInstanceState() : NavigatorState {
    return /* ... */
  }
}

class MyStackNavigator : StackNavigator(...), SavableNavigator {
  /* ... */
}

The latter doesn't really confidently provide a stable API however.

from acorn.