javascript - Youtube - onStateChange 处理一个视频而不是另一个

Question

当您更改 YouTube 视频 ID 时，相同代码的行为会有所不同。

问题是，当您拉动进度 slider 时，它会在一个视频上触发 onStateChange 事件，但不会在另一个视频上触发。检查下面的两个示例，并尝试在两个示例上拉动时间 slider 并观察您的 console.log。

当您拉动时间 slider 时，为什么只有一个视频对 onStateChange 使用react？

两个视频都对播放/暂停按钮 react 良好，但对时间 slider 没有反应……只有一个在工作。

我错过了什么吗？非常感谢任何帮助

Youtube 代码 1(有效): ( http://jsfiddle.net/2t9omgwm/ )

<!-- 1. The <iframe> (and video player) will replace this <div> tag. -->
<div id="player"></div>

<script>
  // 2. This code loads the IFrame Player API code asynchronously.
  var tag = document.createElement('script');

  tag.src = "https://www.youtube.com/iframe_api";
  var firstScriptTag = document.getElementsByTagName('script')[0];
  firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);

  // 3. This function creates an <iframe> (and YouTube player)
  //    after the API code downloads.
  var player;
  function onYouTubeIframeAPIReady() {
    player = new YT.Player('player', {
      height: '390',
      width: '640',
      videoId: 'M7lc1UVf-VE',
      iv_load_policy: 3,
      showinfo:0,
      //videoId: 'Fj73JF_bhjc',
      events: {
        'onReady': onPlayerReady,
        'onStateChange': onPlayerStateChange
      }
    });
  }

  // 4. The API will call this function when the video player is ready.
  function onPlayerReady(event) {
    //event.target.playVideo();
  }

  // 5. The API calls this function when the player's state changes.
  //    The function indicates that when playing a video (state=1),
  //    the player should play for six seconds and then stop.
  var done = false;
  function onPlayerStateChange(event) {
      console.log('state changed');
      //player.seekTo(0, true);
    if (event.data == YT.PlayerState.PLAYING && !done) {
      done = true;
    }
  }

</script>

另一个视频不起作用: ( http://jsfiddle.net/ctgomt7t/ )

<!-- 1. The <iframe> (and video player) will replace this <div> tag. -->
<div id="player"></div>

<script>
  // 2. This code loads the IFrame Player API code asynchronously.
  var tag = document.createElement('script');

  tag.src = "https://www.youtube.com/iframe_api";
  var firstScriptTag = document.getElementsByTagName('script')[0];
  firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);

  // 3. This function creates an <iframe> (and YouTube player)
  //    after the API code downloads.
  var player;
  function onYouTubeIframeAPIReady() {
    player = new YT.Player('player', {
      height: '390',
      width: '640',
      videoId: '0Bmhjf0rKe8',
      iv_load_policy: 3,
      showinfo:0,
      //videoId: 'Fj73JF_bhjc',
      events: {
        'onReady': onPlayerReady,
        'onStateChange': onPlayerStateChange
      }
    });
  }

  // 4. The API will call this function when the video player is ready.
  function onPlayerReady(event) {
    //event.target.playVideo();
  }

  // 5. The API calls this function when the player's state changes.
  //    The function indicates that when playing a video (state=1),
  //    the player should play for six seconds and then stop.
  var done = false;
  function onPlayerStateChange(event) {
      console.log('state changed');
      //player.seekTo(0, true);
    if (event.data == YT.PlayerState.PLAYING && !done) {
      done = true;
    }
  }
</script>

`

Answer 1

onPlayerStateChange 事件因以下原因之一而被触发:

-1 = unstarted

0 = ended

1 = playing

2 = paused

3 = buffering

5 = video cued

我认为您在较长的视频中看到的是当您移动 slider 时为 (3) 缓冲触发的事件。但是，在较短的视频中没有缓冲，因此您看不到事件。

您可以通过将代码更改为读取 console.log('state changed : ' + event.data) 来看到这一点。