#类型别名: EventType

type EventType: 
  | "focus"
  | "blur"
  | "scroll"
  | "wheel"
  | "tap"
  | "longtap"
  | "bgload"
  | "bgerror"
  | "touchstart"
  | "touchmove"
  | "touchcancel"
  | "touchend"
  | "longpress"
  | "transitionstart"
  | "transitioncancel"
  | "transitionend"
  | "animationstart"
  | "animationiteration"
  | "animationcancel"
  | "animationend"
  | "mousedown"
  | "mouseup"
  | "mousemove"
  | "mouseclick"
  | "mousedblclick"
  | "mouselongpress"
  | "keydown"
  | "keyup"
  | "layoutchange"
  | "scrolltoupper"
  | "scrolltolower"
  | "scrollend"
  | "contentsizechanged"
  | "scrolltoupperedge"
  | "scrolltoloweredge"
  | "scrolltonormalstate";