Javascript:什么算作 "User interacting with webpage?"

Question

我正在尝试构建一个 chrome 扩展，当页面上的值发生更改时播放音频文件以提醒用户它已更改。有时它可以工作，但有时它说“play()”方法不被允许，因为“用户没有与网页交互”。
它通常会在第一次加载网页时工作，但是当在同一个站点中导航离开时，它通常会抛出这个错误。
这个问题可以分成两个较小的问题:

什么是 Chrome 中的“用户交互”？我似乎找不到任何关于此的信息。

如果设置了“用户交互”标志，有什么方法可以使用 Javascript 进行检查？

Answer 1

这与 Web Audio API 有关。来自 Mozilla Web Docs :

Browsers have started to implement an autoplay policy, which ingeneral can be summed up as:

"Create or resume context from inside a user gesture".

这是为了防止网页在没有用户交互的情况下在页面加载时发出声音。文档继续说明:

But what does that mean in practice? A user gesture has beeninterpreted to mean a user-initiated event, normally a click event.Browser vendors decided that Web Audio contexts should not be allowedto automatically play audio; they should instead be started by a user.This is because autoplaying audio can be really annoying andobtrusive. But how do we handle this?

When you create an audio context (either offline or online) it iscreated with a state, which can be suspended, running, or closed.

When working with an AudioContext, if you create the audio contextfrom inside a click event the state should automatically be set torunning.

来源: Web Audio API best practices