How to debug Litho Transitions?

  1. Go to litho-core/src/main/java/com/facebook/litho/AnimationsDebug.java and set value of ENABLED flag to True.
  2. Look for log messages with tag "LithoAnimationDebug"

This will let you see how the framework does layout diffing, recognizes what transition key/property pairs need to be animated, picks up start and end values, etc.

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