Krzysztof Kornacki korof

Advanced SCSS

Or, 16 cool things you may not have known your stylesheets could do. I'd rather have kept it to a nice round number like 10, but they just kept coming. Sorry.

I've been using SCSS/SASS for most of my styling work since 2009, and I'm a huge fan of Compass (by the great @chriseppstein). It really helped many of us through the darkest cross-browser crap. Even though browsers are increasingly playing nice with CSS, another problem has become very topical: managing the complexity in stylesheets as our in-browser apps get larger and larger. SCSS is an indispensable tool for dealing with this.

This isn't an introduction to the language by a long shot; many things probably won't make sense unless you have some SCSS under your belt already. That said, if you're not yet comfy with the basics, check out the aweso

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

CSS Layout Debugger

A tweet-sized debugger for visualizing your CSS layouts. Outlines every DOM element on your page a random (valid) CSS hex color.

One-line version to paste in your DevTools

Use $$ if your browser aliases it:

~ 108 byte version

Essential JavaScript Links

I no longer mantain this list. There are lots of other very comprehensive JavaScript link lists out there. Please see those, instead (Google "awesome JavaScript" for a start).

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics

elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent

	// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
	// http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating

	// requestAnimationFrame polyfill by Erik Möller. fixes from Paul Irish and Tino Zijdel

	// MIT license

	(function() {
	var lastTime = 0;
	var vendors = ['ms', 'moz', 'webkit', 'o'];

	(function() {
	var CSSCriticalPath = function(w, d, opts) {
	var opt = opts \|\| {};
	var css = {};
	var pushCSS = function(r) {
	if(!!css[r.selectorText] === false) css[r.selectorText] = {};
	var styles = r.style.cssText.split(/;(?![A-Za-z0-9])/);
	for(var i = 0; i < styles.length; i++) {
	if(!!styles[i] === false) continue;
	var pair = styles[i].split(": ");

	Day 1

	Julian Cheal
	Dancing with Robots
	?

	Tero Parviainen
	Build Your Own AngularJS
	?

	function waitForElement(selector) {
	return new Promise(function(resolve, reject) {
	var element = document.querySelector(selector);

	if(element) {
	resolve(element);
	return;
	}

	var observer = new MutationObserver(function(mutations) {

	import React, { Children } from 'react'
	import Router from 'next/router'
	import smoothScroll from '../utils/smoothScroll'

	// this HOC is taken from https://github.com/zeit/next.js/blob/master/lib/link.js and modified
	export default class LinkSmoothScroll extends React.Component {
	constructor (props) {
	super(props)
	this.linkClicked = this.linkClicked.bind(this)
	}