facebook/react — pull request #2638 by jleplomet (2014-12-02 01:09:42+00:00)
Title: Complete callback for ReactTransitionGroup

Added ability to bind a callback “transitionsComplete” for all transitions (enter/leave) to fire when completed. Currently ReactTransitionGroup only notifies its children when their transitions enter/leave completes (componentDidEnter, componentDidLeave). This pull request also allows ReactTransitionGroup to fire off an complete event when all transitions complete.