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+---
+layout: presentation
+title: Implementing Accessibility
+description: More on how Accessibility is Implemented
+class: middle, center, inverse
+---
+background-image: url(img/people.png)
+
+.left-column50[
+# Welcome to the Future of Access Technologies
+
+Aria & Accessibility Trees: More on how Accessibility is Implemented
+
+{{site.classnum}}, {{site.quarter}}
+]
+---
+name: normal
+layout: true
+class:
+
+---
+# Important Reminder
+
+## This is an important reminder
+## Make sure zoom is running and recording!!!
+## Make sure captioning is turned on
+
+---
+[//]: # (Outline Slide)
+# Learning Goals for today
+
+- Description of this week's assignment
+- More on how accessibility is implemented
+
+---
+# First, Introducing your Website Report
+
+We modified the assignment a bit
+- It's now two weeks long
+- It's optionally a group assignment (with others who reviewed the same website)
+
+---
+# Introduction
+- What is the site or app for
+- How did you assess it
+- Overview table
+
+| Task | Type (Web/Mobile/etc) | Testing Method | UARS found | Who Contributed |
+|------|-----------------------|----------------|--------------|-----------------|
+| ... | ... | ... | ... | |
+|------|-----------------------|----------------|--------------|-----------------|
+
+---
+# Executive Summary
+
+Summarize biggest problems (1-2 paragraphs)
+
+| WCAG | Severe problems | Moderate problems | Minor problems |
+|------|-----------------|-------------------|----------------|
+| ... | ... | ... | ... |
+|------|-----------------|-------------------|----------------|
+
+
+---
+# Details
+More detail on what needs to be done sorted by WCAG #
+
+Include both problems and remedies
+
+Easy to split this up among a group
+
+---
+# Make the report accessible
+- Use headers
+- Use proper color contrast
+- Write alt text for photos
+- Use meaningful hyperlinsk
+- Turn in a word or google doc on Canvas
+
+---
+[//]: # (Outline Slide)
+# Learning Goals for today
+
+- Description of this week's assignment
+- More on how accessibility is implemented
+
+---
+# What is a web page really?
+
+| Content | Structure | Style | Behavior |
+| :--: | :--: | :--: | :--: |
+||
+| Words and Images | HTML | CSS | JavaScript |
+
+---
+# What is a web page really?
+
+| Content | Structure | Style | Behavior |
+| :--: | :--: | :--: | :--: |
+|||
+| Words and Images | HTML | CSS | JavaScript |
+
+---
+# What is a web page really?
+
+| Content | Structure | Style | Behavior |
+| :--: | :--: | :--: | :--: |
+||||
+| Words and Images | HTML | CSS | JavaScript |
+
+
+---
+# What is a web page really?
+
+| Content | Structure | Style | Behavior |
+| :--: | :--: | :--: | :--: |
+|||||
+| Words and Images | HTML | CSS | JavaScript |
+
+---
+# Lifecycle of a browser* loading a page
+
+.left-column40[
+1. Fetch the page
+2. Parse the page
+3. Build up an internal representation of the web page
+4. Display the page
+]
+.right-column60[
+
+]
+.footnote[*: As seen by Chrome]
+
+---
+# Parse and Display the Page
+
+.left-column[
+
+
+]
+
+.right-column[
+1. First line: <!DOCTYPE html>
+ - Ok: need to build an internal representation of the page
+2. Line-by-line, go through the HTML
+ - If one of the tags links to a cascading style sheet (CSS) file, load and parse it
+ - If one of the tags links to Javascript (JS) for behavior, load and parse it
+3. FINALLY display the page…
+]
+
+
+---
+# Understanding content
+
+- There are 100s of tags! See [Mozilla Developer Network](https://developer.mozilla.org/en-US/docs/Web/HTML/Element)!
+- Some simple tags
+ - Title `<title></title>` (which nests inside your `<head></head>`)
+ - Headings `<h1></h1>` .. `<h6></h6>`
+ - Paragraphs `<p>`
+ - Ordered or unordered lists: `<ol></ol>`, `<ul></ul>`, with list elements `<li></li>`
+ - Horizontal rules `<hr />`
+ - Strong `<strong></strong>` which defaults to a bold style and emphasis `<em></em>` which defaults to italicized in most browsers.
+
+---
+# Adding content
+
+- There are 100s of tags! See [Mozilla Developer Network](https://developer.mozilla.org/en-US/docs/Web/HTML/Element)!
+- Some simple tags
+- Some tags add semantic context
+ - `<header></header>`: The header or banner that displays the title of the page
+ - `<main></main>`: The bulk of the content of the page
+ - `<footer></footer>`: The footer is optional but you can put contact info and copyright date in there.
+
+---
+# Adding content
+
+- There are 100s of tags! See [Mozilla Developer Network](https://developer.mozilla.org/en-US/docs/Web/HTML/Element)!
+- Some simple tags
+- Some tags add semantic context
+- Some tags need additional information, added to a tag with attributes
+ - Links to other pages `<a href="filename"></a>`
+ - Links to images `<img src="img.jpg" alt="Description!"/>`
+
+---
+# Adding content
+
+- There are 100s of tags! See [Mozilla Developer Network](https://developer.mozilla.org/en-US/docs/Web/HTML/Element)!
+- Some simple tags
+- Some tags add semantic context
+- Some tags need additional information, added to a tag with attributes
+- Some tags (comments) are important for documentation `<!-- -->`
+
+
+---
+# Cascading Style Sheets (CSS)
+
+- Allows us to change the look and feel of the content on the page
+- Style is separated into a .css file
+ - Makes styling multiple pages easier
+ - Allows changing multiple pages easier
+- Style sheets must be linked to an html page in the <head> for the styles to work
+ `<link href=“style.css†rel=“stylesheet†/>`
+- Great example is [CSS Zen Garden](http://www.csszengarden.com/)
+ - Exercise in [Ed](https://edstem.org/us/courses/38124/lessons/59447/slides/331625)
+
+---
+# CSS
+
+.left-column50[
+- Files consist of one or more rule sets
+- Each rule set has a selector which chooses which HTML elements you want to style
+- Style properties are set with rules which are property/value pairs
+- Syntax is important
+- More on [CSS](https://developer.mozilla.org/en-US/docs/Web/CSS)
+
+]
+
+.right-column50[
+
+
+From [W3Schools](https://code.makery.ch/library/html-css/part3/)
+]
+
+---
+# Layout in CSS
+
+Layout can be [complicated](https://www.amazon.com/CSS-Awesome-Mug-Programmer-Developer/dp/B06Y13QC8N),
+fortunately there is CSS [Flexbox](https://courses.cs.washington.edu/courses/cse154/flexboxducky/) or
+[Grid](https://cssgridgarden.com/)!!
+
+
+
+
+
+---
+# Document Object Model (DOM)
+
+.left-column[
+
+
+]
+
+.right-column[
+- This builds a hierarchy of document elements in what we call the **Document Object Model**
+- The structure of this depends on our HTML (or the toolkit that generates your HTML)
+- The structure of this influences layout
+
+]
+
+---
+# Let's compare that to an app
+
+
+**Interface Programmers** combine library elements according to toolkit rules &
+constraints of architecture (common to all UI toolkits).
+
+Example: let's list all the components of this image:
+
+
+
+**Pause and think:**
+- How does the toolkit know where to put the components on the screen?
+- How does the toolkit know how to draw each component?
+
+???
+discuss with your neighbor
+- what to draw; where to draw it
+---
+# How do we make it more interactive?
+
+
+How about we add a button?
+--
+count: false
+
+
+Wait? When you hear the word "button" in the context of a graphical user
+interface (GUI), what do you think of?
+
+--
+count: false
+
+How to tell a button where to place itself on the screen?
+
+---
+# Placment (layout)
+
+What position do we use? What coordinate system do we use?
+
+- An absolute position relative to the whole phone?
+- A position relative to the whole app, but doesn't include the OS features (like status bars)?
+- A position relative to the direct parent of the button, maybe a window *in* the app
+
+--
+Or should we let the toolkit decide what's best?
+
+---
+# Where should it go?
+.left-column50[
+
+Have to set up the layout first so we can see what we've added
+
+This is a "Layout" problem - all UI toolkits have to support layout.
+
+Layout is complicated because we want layout to handle things like resizing or changing from
+portrait to landscape mode well.
+]
+--
+.right-column50[
+Specified using a <br>
+component hierarchy (a tree)
+
+<div class="mermaid">
+graph TD
+W(ConstraintLayout) --> V[Ab TextView--Hello World!]
+ W --> V1[fa:fa-square Button--Next ]
+
+class W darkblue
+class V1,V blue
+</div>
+
+Android's rendering of the same: 
+]
+
+
+---
+# What should it do?
+
+What do we tell the toolkit about the button?
+
+--
+
+We need to know when the user *interacts* with it
+- This is called *Event Handling* Example:
+
+```java
+Button button = (Button) findViewById(R.id.button);
+button.setOnClickListener(new View.OnClickListener() {
+ @Override
+ public void onClick(View view) {
+ // display a pop up with some text
+ Toast.makeText(getApplicationContext(), "Hello!", Toast.LENGTH_LONG).show();
+ }
+});
+```
+
+---
+# Structure of a toolkit
+
+Structure of a Toolkit
+- Library of components
+- Architecture
+
+Note: these definitions have morphed over time, particularly as things have shifted to cross
+platform development.
+[Here's](https://stackoverflow.com/questions/3057526/framework-vs-toolkit-vs-library/19790148#19790148)
+a reasonable set of definitions.
+
+???
+---
+# Some Comparisons
+
+| Android | Web |
+| --- | --- |
+| Java | HTML/CSS/JS |
+| Layouts | CSS Flexbox or Grid |
+| Interactor Hierarchy | Document Object Model (DOM) |
+| Components | DIVS |
+| Paint objects on a canvas | CSS |
+| `onCreate` | `window.addEventListener("load", init);` |
+| `View.OnClickListener#onClick` | `domElement.addEventListener("click", callback);` |
+
+---
+# Which of these Impacts Accessibility?
+
+| Android | Web | Accessibility (eg s) |
+|--------------------------------|---------------------------------------------------|--------------------------------------|
+| Java | HTML/CSS/JS | Does the toolkit support access? |
+| Layouts | CSS Flexbox or Grid | Comprehension/Magnification |
+| Interactor Hierarchy | Document Object Model (DOM) | Navigation |
+| Components | DIVS | Alternative text (toolkit dependent) |
+| Paint objects on a canvas | CSS | Color choices |
+| `onCreate` | `window.addEventListener("load", init);` | Proper Interaction with access API? |
+| `View.OnClickListener#onClick` | `domElement.addEventListener("click", callback);` | See above |
+
+---
+# End of Deck
+
+