Sets the callback to use to find the epicenter of a Transition. A null value indicates that there is no epicenter in the Transition and onGetEpicenter() will return null. Transitions like Android.Transitions.Explode use a point or Rect to orient the direction of travel. This is called the epicenter of the Transition and is typically centered on a touched View. The NoType:android/transition/Transition$EpicenterCallback;Href=../../../reference/android/transition/Transition.EpicenterCallback.html allows a Transition to dynamically retrieve the epicenter during a Transition.

[Android Documentation]