TweenConstructor<T extends Object> typedef
Null safety
Signature for a Tween factory.
This is the type of one of the arguments of TweenVisitor, the signature used by AnimatedWidgetBaseState.forEachTween.
Instances of this function are expected to take a value and return a tween beginning at that value.
Implementation
typedef TweenConstructor<T extends Object> = Tween<T> Function(T targetValue);