[ue4] event distribution mechanism of reflective event distributor and active call event mechanism

Law 1 Active call event mechanism

1. When an event needs to be sent Actor Get the event that needs to be accepted Actor References to

2. When an event needs to be sent Actor Invoking events that need to be accepted Actor Events

Law 2 Event distribution mechanism of reflective event distributor

1. When an event needs to be sent Actor New event distributor in

2. When an event needs to be sent Actor Calling event dispatcher in

3. When the event needs to be accepted Actor Get the event that needs to be sent Actor References to , Subscribe to events that need to be sent Actor Event dispenser for

One is passive, the other is active , I can't say which is better ……
But from a structural point of view , It's better for an input component to be only responsible for its own affairs , So the way of reflection is better
To put it in detail is , If you want to take the initiative , Need to send events Actor Need to know who needs to accept the event Actor, To call its event . But actually I act as an input port , I'm only responsible for accepting input , I don't want to know who I'm going to give , If I want to know who I need to pass the input to , Then I'm not with the increase of the number of projects , To write a long list of objects that I need to call events ？ This is not elegant , It's easy to make a mistake , Why don't you come and get it yourself , Come and get it if you need it , I don't care who you are , I'm just responsible for giving it out . So there's a lot less code . and , For those who need to accept Events Actor, Although it needs to know what events need to be sent Actor Who is it? , But it happens to be in charge of it ： I need it , I'm going to