What thread are the event handlers running on?

Question

In what thread are event handlers executed (e.g. onAnimationEnd, onTouchEvent, onKeyEvent, onClick)? Are they called sequentially or can two handlers be executed at the same time?

Answer 1

In what thread are event handlers executed (e.g. onAnimationEnd, onTouchEvent, onKeyEvent, onClick)?

The main stream of applications.

Are they called sequentially or can two handlers be executed simultaneously?

They are called sequentially.