Modernizr：包含'videoautoplay'自定义测试时，define是未定义的

Question

当我包含自定义测试videoautoplay（https://github.com/Modernizr/Modernizr/blob/master/feature-detects/video/autoplay.js）时，构建会抛出错误“define is undefined”（参见屏幕截图）。

知道如何解决这个问题吗？

Answer 1

我认为当grunt-modernizr插件只与modernizr 2.7.1兼容时，你试图包含一个modernizr 3.0测试。这有点令人困惑！

正在different branch进行工作，使grunt-modernizr与modernizr 3.0兼容。

以下是2.7.1功能检测：https://github.com/Modernizr/Modernizr/tree/v2.7.1/feature-detects

看起来视频自动播放不存在，因此您可能需要从3.0复制检测并使其适用于2.7.1并将其作为自定义测试包含在内。使用this simple detect作为参考。

Answer 2

我遇到了同样的问题，并编写了一个自定义脚本，用于翻译新的＆＃39;测试＆＃39;进入2.8.3格式，希望有所帮助：

(function(  ){

var timeout;
var waitTime = 200; // Too short will not work.
var elem = document.createElement('video');
var elemStyle = elem.style;

// skip the test if video itself, or the autoplay
// element on it isn't supported
if (!Modernizr.video || !('autoplay' in elem)) {
  Modernizr.addTest('videoautoplay', false);
  return;
} 

elemStyle.position = 'absolute';
elemStyle.height = 0;
elemStyle.width = 0;

try {
    if ( Modernizr.video.ogg ) {
      elem.src = 'data:video/ogg;base64,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';
    }
    else if ( Modernizr.video.h264 ) {
      elem.src = 'data:video/mp4;base64,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';
    }
    else {
      Modernizr.addTest('videoautoplay', false);
      return;
    }
}

catch (e) {
    Modernizr.addTest('videoautoplay', false);
    return;
}

elem.setAttribute('autoplay', '');
elem.style.cssText = 'display:none';
// docElement.appendChild(elem);
document.documentElement.appendChild(elem);

function testAutoplay(arg) {
  clearTimeout(timeout);
  elem.removeEventListener('playing', testAutoplay, false); 
  var result = arg && arg.type === 'playing' || elem.currentTime !== 0;
  Modernizr.addTest("videoautoplay", result);
  elem.parentNode.removeChild(elem);
}

// wait for the next tick to add the listener, otherwise the element may
// not have time to play in high load situations (e.g. the test suite)
setTimeout(function() {
  elem.addEventListener('playing', testAutoplay, false);
  timeout = setTimeout(testAutoplay, waitTime);
}, 0);
})();