Accessibility in Flex

Accessibility in Flex History, Methods, Concerns, Advice Michelle M Bagur Senior Developer, EffectiveUI [email_address] fugaciousness Slideshare.net/fugaciousness

Introduction: What to Expect
Accessibility as a whole
Definitions, history, necessity, complexity
The components that comprise accessibility: the web, assistive devices
Examples (both good and bad)
Accessibility in Flex
My participation in this effort
How it’s supposed to work
Implementation examples (tips and tricks)
The outlook for Flex 4

Definitions and Considerations
Basic definition
Allowing people with disabilities or impairment to use the web or software applications
Not just one group should be targeted.
People who are blind, have motor impairment, the elderly, the hard of hearing

A Little History
Rehabilitation Act - 1973
Prohibits discrimination on basis of disability
Section 508 - 1998
Required Federal agencies to make their electronic and information technology accessible to people with disabilities
Includes not only internally used applications, but any information that is provided to the general public
http://www.section508.gov/ has technical standards, training information, FAQs, forums, etc

Acronyms to Know: WAI, W3C, WCAG
WWW Consortium (W3C)
International consortium of member organizations, full time staff, and the public
Develops interoperable technologies
Forum for communication and ‘collective understanding’
Web accessibility initiative (WAI)
Part of the W3C
Develops accessibility guidelines, reports, and resources to help make the Web available to people with disabilities: WCAG
WCAG (Web content accessibility guidelines)
Created by the WAI
Series of documents, part of a bigger series of accessibility guidelines
Initially published in 1999, Version 2 out in 2008

The Spirit of Things
Principles of accessibility (developed by the WCAG)
Perceivable
Operable
Understandable
Robust
Compliance
How do you know if you comply?
Test against guidelines
Find an impaired user
Combination of automated tools and best judgment
Is the ‘spirit’ of compliance good enough?
Alternative approaches, are they different but equal?

Why Does it Matter?
Target Lawsuit
Why were they sued?
By whom?
What were the results?
Read any blog, there are debates amongst people
Common phrase: Go elsewhere, use another site, businesses will suffer
Not actually the way it works; what if there are no alternatives?
Why Target, if they are not a government agency?

Assistive Technologies
Keyboard Navigation
No extra requirements
Tabbing, hotkeys
Screen Readers
JAWS by Freedom Scientific
Window Eyes by GW Micro
VoiceOver by Apple

How do Screen Readers Work?
MSAA (Microsoft Active Accessibility)
API introduced in 1997
IAccessible COM interface
Four pieces exposed by API: Name, Type, Value, State
UI Automation
Properties
Client asks server
“ give me this info”
get_accRole()
get_accName()
get_accDescription()
get_accState()
get_accValue()
get_accParent()
get_accChildCount()
Events Server notifies client “ this just happened” OBJECT_CREATE OBJECT_DESTROY OBJECT_NAMECHANGE OBJECT_FOCUS OBJECT_SELECTION

Examples: You Decide
Good?
www.Amazon.com
www.dignubia.org (only in IE)
Bad?
www.Target.com
www.Google.com -> www.recipes.com
http://www.w3.org/WAI/wcag-curric/sam26-0.htm
http://examples.adobe.com/flex2/inproduct/sdk/flexstore/flexstore.html

Flex 3 and MSAA
Three main classes:
Flash.accessibility.AccessibilityImplementation
Flash.accessibility.AccessibilityProperties
Flash.accessibility.Accessibility
Compile with –accessible = true:
package mx.controls {
[AccessibilityClass(implementation="mx.accessibility.ButtonAccImpl")] public class Button { … }
}
Initialized with: button.accessibilityImplementation = new
ButtonAccImpl(button)

Example: AccImpl A Button’s MSAA name is the label that it displays, so JAWS speaks the label class ButtonAccImpl extends AccessibilityImplementation { override public function get_accName():String { return label; } }

AccessibilityProperties
Code example
AccPropertiesEx.mxml
Accessibility.active
Accessibility.updateProperties()

How’s it Supposed to Work?
Flex 3:
JAWS 8, 9,or 10
Internet Explorer
JAWS scripts
The chain of command:
Flex SDK
Flash player
JAWS scripts
JAWS

The Official Documentation
28 Accessible components:
Accordion
Advanced Data Grid
Alert Button
Checkbox
ColorPicker
Combobox
DataGrid
DateChooser
DateFeld
Form
Image
Label
LinkButton
List
Menu
MenuBar
Panel
RadioButton
RadioButtonGroup
Slider
TabNavigator
Text
TextInput
TitleWindow
TooltipManager
Tree

Tips and Tricks: Prepare Thyself
Make sure scripts are installed:
Insert + q
Start tabIndex at 1, rather than 0
tabIndex = 1;
Don’t be afraid of the focusThickness property
focusThickness = 3;
Get focus into Flash application (semi successfully)
ExternalInterface.call( "s = function() {document.getElementById('“ + this.id + "').focus(); }" );
Possible method to force the tab to stay within the app
keyFocusChange="event.preventDefault();
focusManager.getNextFocusManagerComponent(event.shiftKey).setFocus()“
Form Validation
Validation message gets added to end of accessibilityName, should
get read when field is focused.

Tips and Tricks: Tooltips
If control has:
Tooltip, no name, no description
Tooltip used for name value and visual tooltip
Tooltip, has name, no description:
Tooltip used for description value and visual tooltip
Tooltip, no name, has description:
Tooltip used for name value and visual tooltip
Tooltip, has name, has description:
Tooltip used only for visual tooltip
Tooltip bugs:
Sometimes they’re just not read: NAB
Can’t read tooltip on textArea if it’s not editable IS a bug

Tips and Tricks: JAWS
Press Enter to move into and out of forms mode. This is no longer on by default , in the newest scripts.
Press Insert + Z to toggle virtual cursor mode. Not possible on a MAC laptop, must be reassigned via JAWS.
Use JAWS Keyboard manager to reassign keys, make changes to voice, change verbosity.
JAWS can take over keystrokes, as there is a long list of preassigned key combinations. Be aware if you’re developing when JAWS is running, you will have issues.

The Outlook for Flex 4
“ We will continue to invest in accessibility in each version of Flex, but sometimes that support will be staggered across releases. In Flex 4 we have fixed a number of bugs, and we hope to continue to do so, including backporting those fixes to Flex 3. We are not implementing accessibility for Spark controls in 4.0, but there will be a follow-up release not too long after that will add support in.
“ We are also investigating the next generation of accessibility support as part of a future version of the Flash Player. Adobe has membership in the relevant committees (like WCAG 2) and we are working with industry leaders to make sure that we're supporting the right things. It will take a release or two for that substantial upgrade to occur, but is definitely on our roadmap.”

Helpful Links and References
http://www.w3.org/WAI/EO/Drafts/PWD-Use-Web/#diff (examples of disabilities and use cases for assistive technology)
http://blog.comtaste.com/2007/06/form_fields_focus_and_keyboard.html (keep focus in flash movie)
http://tinyurl.com/ouccm4 (adobe’s jira accessibility bug list)
http://www.adobe.com/accessibility/products/flashplayer/overview.html (flash 10 and accessibility)
http://msdn.microsoft.com/en-us/library/ms697707.aspx (MSAA description)
http://blogs.adobe.com/accessibility/ (adobe’s blog moderated by Andrew Kirkpatrick)
http://www.section508.gov/ (the accessibility act)
http://v1.boxofchocolates.ca/archives/2006/02/09/taking-aim-at-target-dot-com (articles and comments on target lawsuit)
http://www.w3.org/WAI/ (standards and checklists)
http://www.jimthatcher.com/testing.htm (walkthrough of testing for accessibility)
http:// msdn.microsoft.com/en-us/library/ms788733.aspx (ui automation and MSAA )
https://share.acrobat.com/adc/document.do?docid=e907b423-0407-46da-a75f-87d7468dd997 (newest scripts)

Special Thanks
Gordon Smith: Flex Engineer, Adobe
Jay Proulx: Enterprise Developer Support Consultant, Tier 3, Adobe
Andrew Kirkpatrick: Senior Product Manager, Accessibility, Adobe
John Funk: Solutions Architect, Adobe
Jonathan Avila: Chief Accessibility Officer, SSB Bart
Matt Chotin: Flex Product Manager, Adobe
Matt May: Accessibility Engineer, Adobe

Accessibility in Flex

by fugaciousness on May 19, 2009

Accessibility

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Accessibility in Flex — Presentation Transcript