Interface for holding a Scrollable stationary.
An object that implements this interface is returned by
ScrollPosition.hold. It holds the scrollable stationary until an activity
is started or the cancel method is called.
The hash code for this object. [...]
A representation of the runtime type of the object.
Release the Scrollable, potentially letting it go ballistic if
Invoked when a non-existent method or property is accessed. [...]
Returns a string representation of this object.