Let there be two objects: A and B.

A has a method: A.methodA(), and B also has a method: B.methodB().

Given this situation, please consider the below codes.

(1) Using other object's method directly

methodA() {
  B.methodB();
}

A.methodA(); // B.methodB invoked

(2) Using event to call other object's method

window.addEventListener('call', callcallback);

function callcallback() {
  B.methodB();
}

methodA() {
  window.dispatchEvent('call');
}

A.methodA(); // B.methodB invoked

Both ways will result in calling B.methodB(), but I wonder what is the difference. Also I would like to know which way is better. (Or does each way depend on a situation which it is used?)