mirror of
https://github.com/hanzoai/react.git
synced 2026-09-24 17:02:27 +00:00
It is valuable to know when the number of children in a TransitionGroup is going to increase or decrease, since we might want to apply extra animations. For instance, when used with overflow:auto, we might want to apply different css based on it overflowing or not - to do this we need to calculate this after new nodes has entered and after nodes has been removed.