Learn Canvas, Firefox and Jekyll

Jekyll is a blog-aware static site generator. You can write text in markdown or HTML and Jekyll uses layouts to create a static website. You can tweak how you want the site URLs to look, what data gets displayed on the site, and more.

After watching the collection you'll be able to:

* Install Jeykll and run it locally
* Create a new blog post
* Install plugins to add new features to your blog

Jekyll is a parsing engine bundled as a ruby gem used to build static websites from dynamic components such as templates, partials, liquid code, markdown, etc. Jekyll is known as "a simple, blog aware, static site generator".

jekyll

Create A Blog With Jekyll

A <canvas> element provides scripts with a resolution-dependent bitmap canvas, which can be used for rendering graphs, game graphics, or other visual images on the fly.

canvas

Learn some of the different ways you can affect the graphical content that you are drawing to a canvas. We'll cover global alpha, global composite operations and shadows.

Canvas Effects

With the HTML `canvas` you can easily draw text as well as graphics. Let's take a look at basic text manipulation on the canvas.

Drawing Text on Canvas

In this lesson, we cover several different ways to animate graphics drawn to Canvas.

Animating with Canvas

When drawing on the HTML5 canvas element, your fills aren't limited to flat colors. You can use gradients to get smoothly blended color fills on your drawn elements.

Gradient Fills on the HTML5 Canvas

Transformations can change the default canvas coordinate system and create complex drawings with much less code.

Canvas Transformations

In this lesson, listening for and handling mouse and keyboard events in Canvas is covered.

Listening for Mouse and Keyboard Events with HTML Canvas

The HTML Canvas element allows us to access powerful drawing APIs from JavaScript. In this lesson, the first in a series, we will learn about `<canvas>`, and get ready to start drawing.

Introduction to the HTML Canvas element

Now that we have an HTML5 canvas to draw on, let's take a look at drawing simple lines and rectangles with JavaScript

Drawing Paths - Lines and Rectangles

When drawing on your HTML canvas in JavaScript, you aren't restricted to straight lines. Using curves and arcs you are able to create smooth curved lines.

Drawing Paths - Curves and Arcs

You aren't limited to boring black lines when drawing on the HTML5 canvas element. Using styles, you can program interesting colorful images with JavaScript.

Drawing Styles on HTML5 Canvas

In this lesson, you'll learn how to read and write individual pixel color values from a canvas.

Canvas and Pixels

In addition to vector drawing, you can draw bitmap images into a canvas, and also retrieve a bitmap based on the content in a canvas.

HTML Canvas and Images

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

The React Developer Tools are an extension that can be added to Chrome and Firefox to help with debugging React applications. In this lesson, we walk through how to use these developer tools to view, edit, and debug your React components, including: the `React` browser tab, inspecting components in parallel with the `Elements` tab, using React components in the console, searching by component name, and debugging component state and props.

Debugging components with the React Developer Tools extension

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. 

aria

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

[Jekyll](https://jekyllrb.com/) is a static site generator built in [Ruby](https://www.ruby-lang.org/en/) and available to generate and host websites on [GitHub Pages](https://pages.github.com/). In this course, you'll install the Jekyll gem, use the command line tool to generate a new project, inspect the scaffolded project, and finally, serve the starter website.

Install Jekyll and generate initial, scaffolded website

The `canvas` element exposes a 2d context which allows you to draw lines using the `moveTo`, `lineTo`, and `stroke` api. You can combine this with Mouse events to make a simple drawing app.

Draw with Your Mouse on an HTML Canvas

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

chrome-devtools

The axe browser extension (for Chrome and Firefox) is an immensely helpful tool for auditing web pages for accessibility defects.  This extension is powered by the same rules engine developed by Deque Labs in their axe-core open source library which also powers the react-axe development tool.  Each reported defect offers a ton of information about the defect, why it's a problem, severity level, groups impacted and ways to fix the defect.  This can be a great resource for learning more about how to write accessible code.

## Resources
* [Chrome browser extension](https://chrome.google.com/webstore/detail/axe-web-accessibility-tes/lhdoppojpmngadmnindnejefpokejbdd)
* [Firefox browser extension](https://addons.mozilla.org/en-US/firefox/addon/axe-devtools/)

Use the axe Browser Extension to Audit a Web Page for Accessibility Issues

tota11y is a great tool to add to your accessibility auditing toolkit.  tota11y is a browser extension available for Chrome and Firefox that helps visualize accessibility violations (and successes), while educating on best practices.  It can make for a really helpful supplement to other accessibility auditing tools.

## Resources
* [About tota11y](https://khan.github.io/tota11y/)
* [Chrome browser extension](https://chrome.google.com/webstore/detail/tota11y-plugin-from-khan/oedofneiplgibimfkccchnimiadcmhpe?hl=en)
* [Firefox browser extension](https://addons.mozilla.org/en-US/firefox/addon/tota11y-accessibility-toolkit/)

Use tota11y to Visualize Accessibility Issues

Using our accessibility auditing toolkit we can find issues concerning landmark regions in our web application.  The react-axe library will report findings in the JavaScript console of the browser.  We could also run the axe browser extension to see the same results.  The tota11y browser extension will annotate any landmark regions on the page and therefore if none are annotated it may indicate that they aren't any (_NOTE: tota11y will only annotate landmark regions using aria roles and not those using HTML5 elements_).  Finally using the VoiceOver Rotor in Safari will show us whatever landmark regions have been defined in the Landmarks menu. 

Test for Landmark Region Accessibility Issues in React

Cascading Style Sheets bring order and beauty to our applications.

Firefox DevTools has an awesome feature that helps you determine Inactive CSS, to know why it's inactive, it gives you hints on how to fix it, and even links to documentation for additional help.

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