Update doubleClickInit.js

packages/artplayer/src/events/doubleClickInit.js

@@ -1,6 +1,6 @@
 export default function doubleClickInit(art, events) {
-  const { refs: { $player } } = art;
-  events.proxy($player, 'dblclick', () => {
+  const { refs: { $video } } = art;
+  events.proxy($video, 'dblclick', () => {
     art.player.fullscreenToggle();
     art.emit('dblclick');
   });