allowImplicitScrolling property

bool allowImplicitScrolling
override

Whether a viewport is allowed to change pixels implicitly to respond to a call to RenderObject.showOnScreen.

RenderObject.showOnScreen is for example used to bring a text field fully on screen after it has received focus. This property controls whether the viewport associated with this offset is allowed to change the offset's pixels value to fulfill such a request.

Implementation 

@override
bool get allowImplicitScrolling => physics.allowImplicitScrolling;