Is Shadow DOM fast like Virtual DOM in React.js?

They are different things for different purposes, so comparing performance doesn’t make sense. Virtual DOM Virtual DOM is about avoiding unnecessary changes to the DOM, which are expensive performance-wise, because changes to the DOM usually cause re-rendering of the page. Virtual DOM also allows to collect several changes to be applied at once, so not … Read more

window.onload seems to trigger before the DOM is loaded (JavaScript)

At the time window is loaded the body isn’t still loaded therefore you should correct your code in the following manner: <script type=”text/javascript”> window.onload = function(){ window.document.body.onload = doThis; // note removed parentheses }; function doThis() { if (document.getElementById(“myParagraph”)) { alert(“It worked!”); } else { alert(“It failed!”); } } </script> Tested to work in FF/IE/Chrome, … Read more

is there an alternative to DOMAttrModified that will work in webkit

Although Chrome does not dispatch DOMAttrModified events, the more lightweighted mutation observers are supported since 2011 and these work for attribute changes, too. Here is an example for the document body: var element = document.body, bubbles = false; var observer = new WebKitMutationObserver(function (mutations) { mutations.forEach(attrModified); }); observer.observe(element, { attributes: true, subtree: bubbles }); function … Read more

Access HTML attribute value in SASS

Sass is just a CSS generator. It doesn’t really interact with your HTML, so you can’t use HTML attributes as Sass variables. However, CSS can select based on attributes. So it will be more long-winded than you might like, but you can do something like ul[data-count=”3″]:after content: “There were three items in that list!” And … Read more