Learn Aria, Clojurescript and Edge

A large number of people are unable to use the web effectively due to an impairment or disability.

As developers there are several tools and techniques we can use to make our web applications accessible, ensuring a great user experience that includes everyone.

We all agree that Accessibility is important. However, it’s a broad landscape and can be overwhelming figuring out where to start!

Erin Doyle is an expert in creating accessible React applications and has developed a course that will give you a concrete process for testing, refactoring, and building your applications with accessibility in mind.

After this course, you'll have a jump start on auditing and fixing accessibility issues in your applications and gain a better understanding of your target users and how to approach your web app design from their perspectives.


React is one of the web’s most popular frameworks for building JavaScript applications. 

If you know what you’re doing, React can drastically simplify how you build, use, and maintain code.

Whether you’re a React newbie or you’re ready for advanced techniques, you can level-up with egghead. Explore our in-depth courses, lessons, and community resources to build more powerful applications and crack open your career.

react

Develop Accessible Web Apps with React

Accessibility (or a11y) is an important but often neglected in the world of web development. Many developers find themselves coding user interfaces without any knowledge of keyboard or screen reader requirements. 

The fact is that accessibility doesn't happen by accident. Often it is seen as too hard or time consuming. This doesn't have to be the case. By following a handful of high-value patterns and practices, we can open our web apps to humans that otherwise wouldn't be able to interact with them at all.

This course will introduce you to accessibility through hands-on, technical examples that are way more effective than reading 10-year-old static web content.



WAI-ARIA, the Accessible Rich Internet Applications Suite, defines a way to make Web content and Web applications more accessible to people with disabilities. It especially helps with dynamic content and advanced user interface controls developed with Ajax, HTML, JavaScript, and related technologies. 

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Start Building Accessible Web Applications Today

Skeleton screens show users that content is loading, offering a vague preview of how content will look once it fully loads.

CSS Animations are crucial for the perceived performance purposes since it shows for the user the content is loading by using animations as feedback for whoever is accessing the page. 

Follow the steps in this course and you will learn how to create a beautiful and pleasant Skeleton Loader for your web app using CSS animations, focusing on Web Accessibility and Web Semantic.

Creating Accessible Skeleton Loader Animation from Scratch with HTML and CSS

AngularJS is an open-source JavaScript framework, maintained by Google, that assists with running single-page applications. Its goal is to augment web-based applications with model–view–controller (MVC) capability, in an effort to make both development and testing easier.

angularjs

Themes convey meaning through color, tones, and contrasts. And the theme color palettes, alphas, and shadows deliver a consistent tone to your application and a unified feel for all Angular Material UI components. Theming allows developers to change the intention and meaning of the application by changing the colors and shadows. 

Accessibility is a huge - often overlooked - feature in modern web applications. Angular Material components all implement ARIA features whenever possible. And for usage scenarios where the ARIA attributes are not explicitly provided and cannot be inferred, then Angular Material will provide details console warnings alerting the developer.

Let’s use the Angular Material Theming service to change the background, primary, accent, and warning colors used within the entire application. These will be configured at startup using the $mdThemeProvider.  

Let’s also resolve the two ARIA warnings shown in console. These originate from icon buttons where the ARIA label cannot be inferred. So let’s add a static aria-label and a dynamic, interpolated aria-label to those buttons.

> This course presented by Thomas Burleson and Aaron Frost

Angular Material: Theming and ARIA

Icon buttons are very common in web applications, yet they often have accessibility problems. Learn how to make your icon buttons accessible to keyboard and screen reader users with HTML, CSS, SVG and ARIA.

Accessible Icon Buttons

Are you building a website or web application that takes user input? Then it's important for you to watch this demo. Learn how to create more accessible forms using basic HTML form labels, fieldsets and legends. You'll even learn a bit about what makes Safari's developer tools pretty awesome.

Building Forms with Accessibility in Mind

Webpages are more than simply how they look. By coding with headings, landmarks and semantic HTML, you can expose a rich document outline to users of assistive technologies, as well as search engines. 

Headings and semantic structure for accessible web pages

edge

Coding for accessibility? You should get familiar with the accessibility tree, a structure produced by platform Accessibility APIs running parallel to the DOM, which exposes accessibility information to assistive technologies such as screen readers. There are multiple tools for visualizing this tree; in this lesson we'll look at Chrome and Microsoft Edge. For more on Accessibility APIs, refer to this [amazing article by Leonie Watson](https://www.smashingmagazine.com/2015/03/web-accessibility-with-accessibility-api/). For a how-to on setting up the Chrome Accessibility Inspector, visit [bit.ly/chrome-a11y](http://bit.ly/chrome-a11y).

What is the Accessibility Tree?

What is this thing called ARIA? In this lesson, you'll learn about about WAI-ARIA, a.k.a. Accessible Rich Internet Applications, the W3C spec for specifying accessibility information in HTML and SVG. I cover the basics of applying ARIA roles, states and properties, helpful information for creators of user-interface widgets and component libraries. But it's important to note that you might not need ARIA at all! Before using it, it's important to educate yourself on what ARIA does and doesn't do for you.

Intro to ARIA

Learn how to create a modal dialog with accessible keyboard and screen reader mechanics using the native HTML5 dialog element and experimental inert attribute (with polyfills) and JavaScript focus management. We'll explore how to make a DIV or non-modal dialog into a modal one to contrast the differences. Finally, we'll expose accessibility information for NVDA, Voiceover, JAWS and other screen readers.

For more details on creating accessible dialog content, check out this great article by Marco Zehe, Advanced ARIA Tip #2: Accessible Modal Dialogs: https://www.marcozehe.de/2015/02/05/advanced-aria-tip-2-accessible-modal-dialogs/

### Used in this lesson:
- Google dialog element polyfill: https://github.com/GoogleChrome/dialog-polyfill
- Inert attribute polyfill: https://github.com/WICG/inert

Accessible modal dialogs

Learn the basics of web accessibility testing using the keyboard, [Web Developer Toolbar](https://addons.mozilla.org/en-US/firefox/addon/web-developer/), [aXe Firefox extension](https://addons.mozilla.org/en-us/firefox/addon/axe-devtools/), and Lea Verou's [Contrast Ratio](http://leaverou.github.io/contrast-ratio/) tool. We'll look at how to get an overview of a webpage's accessibility, with special attention paid to solving color contrast issues.

For more on accessibility auditing, check out this article: https://marcysutton.com/how-i-audit-a-website-for-accessibility/

Basic accessibility testing

Testing for accessibility is easy with automated tools like axe-cli. This command-line tool utilizes the open source axe-core JavaScript library to run an audit on any webpage you give it, returning a set of JSON results you can use in your continuous integration environment or regular development workflow. 

- [axe-cli](https://github.com/dequelabs/axe-cli)
- [axe-core](https://https://github.com/dequelabs/axe-core)
- [aXe Chrome](https://chrome.google.com/webstore/detail/axe/lhdoppojpmngadmnindnejefpokejbdd?hl=en-US)

Accessibility testing with axe-cli

Often buttons need to be handled by JavaScript, and if done improperly it can lead to accessibility issues. In this lesson you will improve a major news organization's global header with some basic HTML and JavaScript.

Accessible Button Events

ASP.NET is an open source web framework for building modern web apps and services with .NET. ASP.NET creates websites based on HTML5, CSS, and JavaScript that are simple, fast, and can scale to millions of users.

asp-net

If you want to improve a REST API beyond GET/POST&PUT and DELETE the next step would be adding the push functionality to send new data into your web applications. With ASP.NET Core and SignalR you can add this functionality with ease and keep your application up to date without letting the clients reloading their page manually.

[signalr npm](https://www.npmjs.com/package/@aspnet/signalr), [signalr Core](https://www.nuget.org/packages/Microsoft.AspNetCore.SignalR.Core/)

[archived] Expose Values for Real-time Consumption with SignalR in ASP.NET Core

Animations can make people sick, or worse! By adding animation toggles and listening in to the user's system preference for reducing motion on OSX and iOS, we can give them more control over our interfaces. Animation can be a safety issue; let's do something about it!

Warning: there is a flashing animation in the video.

In this lesson:
- [prefers-reduced-motion](https://webkit.org/blog/7551/responsive-design-for-motion/)

WCAG 2.1, Guideline 2.3: Seizure risks
- https://www.w3.org/WAI/WCAG21/quickref/?versions=2.0#qr-seizure-does-not-violate

Your Interactive Makes Me Sick
- https://source.opennews.org/articles/motion-sick/

Accessible animations with reduced motion

Because we'll be controlling our markup via JSX, we can use ESLint to check our markup for potential accessibility issues based on static analysis of the code. In this lesson, we'll install, configure and run the `jsx-a11y` ESLint plugin.

Check for Accessibility Issues in JSX with the jsx-a11y ESLint Plugin

The jsx-a11y lint plugin is a great first line of defense to prevent accessibility issues, but no tool can cover everything. React-axe gives us a runtime check on our rendered DOM, and by adding it to our boilerplate, we’ll ensure that all our future projects have accessibility covered from multiple angles. In this lesson, we’ll install react-axe and add it to our entry point for development builds only.

Check for Accessibility Issues in the Browser with react-axe

ClojureScript is a compiler for Clojure that targets JavaScript. It emits JavaScript code which is compatible with the advanced compilation mode of the Google Closure optimizing compiler.

clojurescript

In this lesson I show you how to get and manipulate command-line arguments in Clojure/ClojureScript by writing a small program that greets you by name. I also show how comments are delimited, how to get a value out of a sequence, how to bind a symbol to a value, and how to define a function.

Handle command-line arguments in ClojureScript


Clojure is a dynamic, general-purpose programming language, combining the approachability and interactive development of a scripting language with an efficient and robust infrastructure for multithreaded programming. Clojure is a compiled language, yet remains completely dynamic – every feature supported by Clojure is supported at runtime. Clojure provides easy access to the Java frameworks, with optional type hints and type inference, to ensure that calls to Java can avoid reflection.

clojure

In this lesson I show what a Clojure keyword is and why we prefer them as keys in maps; and the three ways we can look up a value in a map.

Keywords and Map Lookup in Clojure and ClojureScript

The Chrome Developer Tools (DevTools for short), are a set of web authoring and debugging tools built into Google Chrome.

chrome-devtools

What's in a name? In this lesson, I'll explain the concept of naming interactive elements for screen reader users, including forms, buttons, and links. You'll learn how to debug accessible names and descriptions using the Chrome Accessibility Developer Tools (previously a Canary experiment, now in Chrome), using multiple labeling techniques. We'll also listen to the effects of proper accessible names and descriptions in Voiceover and Safari.

For more information and the nitty-gritty browser implementation algorithm, refer to WAI-ARIA 1.1: 
- https://www.w3.org/TR/wai-aria-1.1/#namecalculation
- https://www.w3.org/TR/accname-1.1/

What is Accessible Name Calculation?

Our first layer of defense when building accessible React applications is to add some auditing tools to our development workflow. This should include adding static analysis checking for common accessibility standards and best practices. We can get this with the latest eslint plugin: "eslint-plugin-jsx-a11y". If you are already linting your projects adding this plugin should fit very smoothly into your workflow.

## Resources
1. [List of all the rules supported by eslint-plugin-jsx-a11y](https://github.com/evcohen/eslint-plugin-jsx-a11y#supported-rules)
2. [Comparison of the difference in rules between recommended and strict mode](https://github.com/evcohen/eslint-plugin-jsx-a11y#difference-between-recommended-and-strict-mode)
3. [Background on how the Accessibility API implemented by browsers interfaces with Assistive Technologies](https://github.com/evcohen/eslint-plugin-jsx-a11y#some-background-on-wai-aria-the-ax-tree-and-browsers)