From 1237ee6c2c1f44aa6dfd0c81fad7e622cb773c5c Mon Sep 17 00:00:00 2001
From: chenjiahan <chenjiahan@youzan.com>
Date: Fri, 28 Aug 2020 14:05:20 +0800
Subject: [PATCH] types: fix event listener typing

---
 src/composition/use-lock-scroll.ts |  8 ++++----
 src/composition/use-touch.ts       | 14 +++++++-------
 src/utils/dom/event.ts             | 10 ++++++----
 3 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/src/composition/use-lock-scroll.ts b/src/composition/use-lock-scroll.ts
index 9783b2090..41d2da242 100644
--- a/src/composition/use-lock-scroll.ts
+++ b/src/composition/use-lock-scroll.ts
@@ -8,7 +8,7 @@ const CLASSNAME = 'van-overflow-hidden';
 export function useLockScroll(element: HTMLElement) {
   const { start, move, deltaY, direction } = useTouch();
 
-  function onTouchMove(event: TouchEvent) {
+  const onTouchMove = ((event: TouchEvent) => {
     move(event);
 
     if (direction.value !== 'vertical') {
@@ -29,9 +29,9 @@ export function useLockScroll(element: HTMLElement) {
     if (prevent) {
       preventDefault(event, true);
     }
-  }
+  }) as EventListener;
 
-  function lock() {
+  const lock = () => {
     if (!count) {
       document.body.classList.add(CLASSNAME);
     }
@@ -39,7 +39,7 @@ export function useLockScroll(element: HTMLElement) {
     count++;
     on(document, 'touchstart', start);
     on(document, 'touchmove', onTouchMove);
-  }
+  };
 
   lock();
 
diff --git a/src/composition/use-touch.ts b/src/composition/use-touch.ts
index e79d98986..7d37889d0 100644
--- a/src/composition/use-touch.ts
+++ b/src/composition/use-touch.ts
@@ -23,21 +23,21 @@ export function useTouch() {
   const offsetY = ref(0);
   const direction = ref('');
 
-  function reset() {
-    direction.value = '';
+  const reset = () => {
     deltaX.value = 0;
     deltaY.value = 0;
     offsetX.value = 0;
     offsetY.value = 0;
-  }
+    direction.value = '';
+  };
 
-  function start(event: TouchEvent) {
+  const start = ((event: TouchEvent) => {
     reset();
     startX.value = event.touches[0].clientX;
     startY.value = event.touches[0].clientY;
-  }
+  }) as EventListener;
 
-  function move(event: TouchEvent) {
+  const move = ((event: TouchEvent) => {
     const touch = event.touches[0];
     deltaX.value = touch.clientX - startX.value;
     deltaY.value = touch.clientY - startY.value;
@@ -47,7 +47,7 @@ export function useTouch() {
     if (!direction.value) {
       direction.value = getDirection(offsetX.value, offsetY.value);
     }
-  }
+  }) as EventListener;
 
   return {
     move,
diff --git a/src/utils/dom/event.ts b/src/utils/dom/event.ts
index 073df3899..baaf9de3e 100644
--- a/src/utils/dom/event.ts
+++ b/src/utils/dom/event.ts
@@ -1,7 +1,5 @@
 import { inBrowser } from '..';
 
-type EventHandler = (event: Event) => void;
-
 // eslint-disable-next-line import/no-mutable-exports
 export let supportsPassive = false;
 
@@ -23,7 +21,7 @@ if (inBrowser) {
 export function on(
   target: EventTarget,
   event: string,
-  handler: EventHandler,
+  handler: EventListenerOrEventListenerObject,
   passive = false
 ) {
   if (inBrowser) {
@@ -35,7 +33,11 @@ export function on(
   }
 }
 
-export function off(target: EventTarget, event: string, handler: EventHandler) {
+export function off(
+  target: EventTarget,
+  event: string,
+  handler: EventListenerOrEventListenerObject
+) {
   if (inBrowser) {
     target.removeEventListener(event, handler);
   }