JavaScript / YouTube API - 未定义变量 YT

Question

我正在创建一个通过YT api嵌入的youtube播放器，但我不断收到未定义变量YT的警报。我可以看到 youtube API 的脚本被包含，它应该创建变量 YT - 那么为什么这不起作用呢？它适用于我网站的其他地方。

这是链接：

http://oncreativity.tv/site/single/4/7CtQaTmEuWk

和我的代码：

<script>
 $(document).ready(function() {
    var tag = document.createElement('script');
    tag.src = "http://www.youtube.com/player_api";
    var firstScriptTag = document.getElementsByTagName('script')[0];
    firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);
    var player;
    var videoSupport = Modernizr.video;
    var ua = navigator.userAgent.toLowerCase();
    var vid = {};
    var params = { allowScriptAccess: "always" };
    var atts = { id: "video_player_flash" };
    {exp:channel:entries channel="creators" dynamic="off" entry_id="{segment_3}" sort="asc" limit="1"}  
    vid.description = "{creator_description}";
    vid.videoID = '{segment_4}';
    vid.link = encodeURI("{creator_link}");
    vid.title = "{title}";
    vid.photos = [];
    {creator_work}  
        vid.photos[{row_index}] = {};
        vid.photos[{row_index}].url = "{work_img}";
        vid.photos[{row_index}].title = "{work_title}";
    {/creator_work}
    {/exp:channel:entries}
    var $vidContainerRef = $('#video_player_container');
    var $vidPlayer = $('<div id="video_player"/>');
    $vidContainerRef.append($vidPlayer);
    vidID = vid.videoID;
    player = new YT.Player('video_player', {
        width: '768',
        height: '432',
        videoId: vidID,
        events: {
            'onReady': onPlayerReady,
            'onStateChange': onPlayerStateChange
        }
    });
});
</script>

Answer 1

您需要将 YT 调用包装在一个函数中，并在包含脚本时调用它。或者，可以从文件添加脚本，而不是调用该脚本来包含另一个脚本。

function doYT(){
    window.player = new YT.Player('video_player', {
        width: '768',
        height: '432',
        videoId: vidID,
        events: {
            'onReady': onPlayerReady,
            'onStateChange': onPlayerStateChange
        }
    }
}
window.YT && doYT() || function(){
    var a=document.createElement("script");
    a.setAttribute("type","text/javascript");
    a.setAttribute("src","http://www.youtube.com/player_api");
    a.onload=doYT;
    a.onreadystatechange=function(){
        if (this.readyState=="complete"||this.readyState=="loaded") doYT()
    };
    (document.getElementsByTagName("head")[0]||document.documentElement).appendChild(a)
}();

Answer 2

这是我

最喜欢的方法。使用 jQuery FYI。

var player = {
    playVideo: function(container, videoId) {
        if (typeof(YT) == 'undefined' || typeof(YT.Player) == 'undefined') {
            window.onYouTubePlayerAPIReady = function() {
                player.loadPlayer(container, videoId);
            };
            $.getScript('//www.youtube.com/player_api');
        } else {
            player.loadPlayer(container, videoId);
        }
    },
    loadPlayer: function(container, videoId) {
        window.myPlayer = new YT.Player(container, {
            playerVars: {
                modestbranding: 1,
                rel: 0,
                showinfo: 0,
                autoplay: 1
            },
            height: 200,
            width: 200,
            videoId: videoId,
            events: {
                'onStateChange': onPlayerStateChange
            }
        });
    }
};
var containerId = 'ytplayer';
var videoId = 'abc123';
player.playVideo(containerId, videoId);