How to describe the relationship between the object and the handler of some events that occur with the object?

Question

IT terminology

How do you describe the relationship between an object and a handler for some of the events that happen to the object?
Example. There is a button. When pressed, a procedure is called. Does it "hang" on the button, "sit" on it, or "attached" to the button? Suggest your options.
ps Spontaneous study of folklore and professional slang.

Answer 1

The procedure is hung on the button.
On click , the procedure is called.