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• 句法
• 范例
• 规范
• 浏览器兼容性
• 相关话题

MediaSession 方法 setPositionState() is used to update the current document's media playback position and speed for presentation by user's device in any kind of interface that provides details about ongoing media. This can be particularly useful if your code implements a player for type of media not directly supported by the browser.

调用此方法在 navigator 对象的 mediaSession 对象。

句法

navigator.mediaSession.setPositionState(stateDict);
					

参数

stateDict 可选

An object conforming to the MediaPositionState dictionary, providing updated information about the playback position and speed of the document's ongoing media. If the object is empty, the existing playback state information is cleared.

返回值

undefined .

异常

TypeError

This error can occur in an array of circumstances:

• 指定 MediaPositionState 对象的 duration is missing, negative, or null .
• 位置 is missing or null, or is either negative or greater than duration .
• playbackRate 为 0。

范例

In this example, a player for a non-standard media file format, written in JavaScript, uses setInterval() to establish a callback which fires once per second to refresh the position information by calling setPositionState() . If the media is still playing when the interval is fired, setPositionState() is called with an object that specifies the duration, playback rate, and position as reported by a myMedia object that describes the track being played.

If the media is not playing, clearInterval() is used to remove the interval handler.

let positionInterval = window.setInterval(() => {
  if (myMedia.isPlaying) {
    navigator.mediaSession.setPositionState({
      duration: myMedia.trackDurationInSeconds,
      playbackRate: myMedia.playbackRate,
      position: myMedia.trackPlayPositionInSeconds
    });
  } else {
    window.clearInterval(positionInterval);
  }
}, 1000);
					

规范

规范	状态	注释
Media Session Standard The definition of 'MediaSession.setPositionState()' in that specification.	草案	初始定义。

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
setPositionState()	Chrome 73	Edge ≤79	Firefox No	IE No	Opera Yes	Safari ?	WebView Android No	Chrome Android 57	Firefox Android No	Opera Android No	Safari iOS ?	Samsung Internet Android 7.0

图例

完整支持

完整支持

不支持

不支持

兼容性未知 ?

兼容性未知

实验。期望将来行为有所改变。

实验。期望将来行为有所改变。

元数据

• 最后修改： Dec 16, 2019

相关话题

1. 媒体会话 API
2. MediaSession
3. 特性

   1. metadata
   2. playbackState
4. 方法

   1. setActionHandler()
   2. setPositionState()
5. Related pages for Media Session API

   1. MediaMetadata