onIdle property Null safety

(Widget Function?()?) onIdle

Widget to display when the widget is first rendered and before executing any method.

It has the third priority after onWaiting and onError. That is, if none of the observed ReactiveModels is on the waiting nor on the error state, and if at least one of them is in the idle state this callback will be invoked.


final Widget Function()? onIdle;