The completion block called at the end of an interactive transition for a collection view.
- iOS 7.0+
- tvOS 9.0+
This completion block takes the following parameters:
A Boolean indicating whether the animations ran to completion.
A Boolean indicating whether the transition finished or was canceled. This parameter is
trueif the transition ran to completion and the new layout is installed. It is
falseif the user canceled the transition and the old layout is installed.