javascript - Vue2 writes its own transition component, why can't it be bound using the new class method?

Question

Why is the event of picture 1 not bound? It is bound when I use method 2. Why is this?
Picture 1

Picture 2

Answer 1

https://cn.vuejs.org/v2/api/#...

on: should be followed by Object or Function

There is still a difference between new Class and using {} to directly create an Object