Note:

If you want to create a new page for developers, you should create it on the Moodle Developer Resource site.

Accessibility: Difference between revisions

From MoodleDocs
m (updated Mark Pilgram's website link - his work was taken off the web)
(40 intermediate revisions by 13 users not shown)
Line 1: Line 1:
Websites built with '''accessibility''' in mind are flexible in meeting different user needs, preferences and situations. Though these methods can increase [[Development:Usability|usability]] for everyone who uses the web they are often legally required to be implemented in a specific effort to prevent discrimination against people with disabilities.
Websites built with '''accessibility''' in mind are flexible in meeting different user needs, preferences and situations. Though these methods can increase [[Usability|usability]] for everyone who uses the Web they are often legally required to be implemented in a specific effort to prevent discrimination against people with disabilities.
 
See the tracker under [http://tracker.moodle.org/browse/MDL-7396 Accessibility Compliance in Moodle 1.8] and [http://tracker.moodle.org/browse/MDL-7860 Compliance with Italian Legislation on Accessibility] for more information on what we are doing for Moodle 1.8.
 


== Starting points ==
== Starting points ==
Line 9: Line 6:
* [http://www.w3.org/WAI/intro/accessibility.php Web Accessibility Initiative's ''Introduction to Web Accessibility'']
* [http://www.w3.org/WAI/intro/accessibility.php Web Accessibility Initiative's ''Introduction to Web Accessibility'']
* [http://diveintoaccessibility.info/ Mark Pilgrim's ''Dive into Accessibility'']
* [http://diveintoaccessibility.info/ Mark Pilgrim's ''Dive into Accessibility'']
* [http://joeclark.org/book/ Joe Clark's ''Building Accessible Websites'' book]
* [http://joeclark.org/book/ Joe Clark's ''Building Accessible Websites'' book]  
 
== Moodle Accessibility Collaboration Group ==
To improve the accessibility/usability of this learning management system, we have established this collaboration group to work together with Moodle developers, administrators, IT professionals, and other interested entities and individuals. We welcome anyone who is interested in improving the accessibility of Moodle to join this group. You don’t need to be a technical guru or accessibility expert to join; however, it is expected that you are familiar with the basics of accessibility and are willing to dedicate a few hours each month to this collaboration effort.


== Standards, guidelines and legislation ==
Visit http://collaborate.athenpro.org/group/moodle to join the mailing list.


=== International & USA ===
We meet in regional groups once a month to discuss accessibility priorities for each region. Regions meet at the following times:
 
* North America: We meet on the 1st Monday of each month at 10am USA Pacific Daylight Saving Time/5pm UTC. (Time zone converter: http://www.worldtimebuddy.com/)
* Europe: Looking for leadership and members
* Asia Pacific: Looking for leadership and members
* Latin America: Looking for leadership and members
 
To review past regional meetings or to see up coming meetings visit http://collaborate.athenpro.org/group/moodle/teleconferences/
 
== Moodle-related accessibility coding guidelines ==
 
; Use CSS, but still use headings, strong and emphasis
: It is generally a good idea to separate a document's content HTML from how it is presented using CSS. There are some tags that affect a document's presentation but also contribute to the structure and meaning of the content. These tags should remain in HTML. This includes heading tags <code><h1>, <h2>, <h3>...</code>, which are used to form the document's hierarchical structure, and <code><strong></code> and <code><em></code> tags, which are used to add meaning to sections of text.
; Avoid using background images for important information
: Users of non-visual browsers cannot see images. They can read the <code>alt</code> tags of normal images, but background images are not presented like normal images.
; Image <code>alt</code> and <code>title</code> attributes
* An <code>alt</code> attribute is required (even if empty) on all images.
* If a link is wrapping an <code><img></code>, the <code><img></code> does not need a <code>title</code> attribute if the link has one.
* The <code>alt</code> for an image and the <code>title</code> for its surrounding link should usually differ. An image <code>alt</code> attribute provides a text equivalent to an image, whereas a <code>title</code> attribute adds supplementary information about the purpose or action associated with an image link. Simply repeating the same text in <code>alt</code> and <code>title</code> attributes adds little and can be annoying for screen reader users.
; Links and buttons should be selectable and easily click-able
* An image used as an icon for a user to click should be large enough so that the user can click on it easily.
* Users should be able to navigate to all links and buttons using the keyboard.
* Generally we should avoid having two buttons/links that achieve the same action in the same area. This can be annoying and confusing for users of screen readers.
; Support dynamic interaction with [[ARIA]] attributes
: Events triggered by AJAX and JavaScript can be less obvious to users of non-visual browsers. [[ARIA]] attributes can assist users of such browsers to follow a dynamic change.
; Use labels with inputs
: Context can easily be lost without a visual presentation. Labels are needed on all input input elements (except button) to describe their purpose in a form. Labels should be unique on a page. Repeated elements should have a unique label that identifies the element within its context.
; Use appropriate page titles
: A page title is a starting point for a screen reader. Page titles should be unique and should make sense for the page. Avoid generic page titles.
; All pages should be navigable using just a keyboard
: It should be possible navigate to all points on a page just using a keyboard. Important events triggered by a mouse event should be able to be triggered when the item receives focus through keyboard navigation.
; Avoid using colour alone to express meaning
: Colour-blind users need additional information to gain meaning if colour is used as the emphasising feature. Also keep in mind that colours can have differing significance in different cultures, so colours should be configurable either through settings or language files.
; Use sufficient color contrast when adding color to text. See Tracker ticket MDL 522391: https://tracker.moodle.org/browse/MDL-52391.
; Role for button-type links
: If a link acts as a button (not forwarding to another page, which is often the case when combined with Javascript), it should declare the ''role'' attribute ''button''. Also, as a button is usually triggered by the Space bar, the Javascript should add proper event listeners on the link to accept this key. Read more at [https://developer.mozilla.org/en-US/docs/Accessibility/ARIA/ARIA_Techniques/Using_the_button_role Mozilla Developer Network]
 
== Web standards, guidelines and legislation ==
 
=== International ===


* [http://www.w3.org/WAI/ Web Accessibility Initiative]
* [http://www.w3.org/WAI/ Web Accessibility Initiative]
Line 19: Line 58:
** [http://www.w3.org/WAI/intro/wcag20 Web Content Accessibility Guidelines 2.0 (draft)]
** [http://www.w3.org/WAI/intro/wcag20 Web Content Accessibility Guidelines 2.0 (draft)]
*** An article on the [http://www.alistapart.com/articles/tohellwithwcag2 problems with WCAG2] from A List Apart
*** An article on the [http://www.alistapart.com/articles/tohellwithwcag2 problems with WCAG2] from A List Apart
** [http://www.w3.org/TR/WCAG20-TECHS/client-side-script.html Client-side scripting guidelines]
* [http://www.w3.org/WAI/intro/aria.php W3C ARIA]
* [http://webaim.org/techniques/forms/controls WebAIM Form Accessibility guidelines]
* [http://webaim.org/techniques/aria/ WebAIM ARIA guidelines]
=== USA ===
* [http://www.section508.gov/ Section 508]
* [http://www.section508.gov/ Section 508]


=== Other countries ===
=== UK ===
* UK:  
* [http://www.legislation.gov.uk/ukpga/2010/15/contents Equality Act 2010], in particular:
: [http://www.parliament.the-stationery-office.co.uk/pa/ld200001/ldbills/003/2001003.htm SENDA - Special Educational Needs and Disability Act/Bill]
** [http://www.legislation.gov.uk/ukpga/2010/15/section/20 Section 20 - Duty to make adjustments]
: [http://www.opsi.gov.uk/acts/acts1995/1995050.htm Disability Discrimination Act 1995]  
** [http://www.legislation.gov.uk/ukpga/2010/15/section/29 Section 29 - Provision of services, etc.]
** [http://www.legislation.gov.uk/ukpga/2010/15/schedule/25 Schedule 25 - Information society services].
* Germany:
: See also the [http://www.equalityhumanrights.com/uploaded_files/EqualityAct/servicescode.pdf Equality Act 2010 Statutory Code of Practice] (PDF) for Services, public functions and associations.
: [http://www.einfach-fuer-alle.de/artikel/bitv/ Barrierefreie Informationstechnik-Verordnung - BITV]
* [http://www.equalityhumanrights.com/advice-and-guidance/public-sector-equality-duty/ Public sector equality duty] created by the Equality Act 2010.
* [http://www.parliament.the-stationery-office.co.uk/pa/ld200001/ldbills/003/2001003.htm SENDA - Special Educational Needs and Disability Act/Bill]
* [http://www.opsi.gov.uk/acts/acts1995/1995050.htm Disability Discrimination Act 1995] (now merged ino the Equality Act 2010).
* [https://www.access8878.co.uk/getting-started-with-bs-8878/16-steps.aspx BS 8878:2010 – 16 Steps for an accessible web product]
 
=== Germany ===
* [http://www.einfach-fuer-alle.de/artikel/bitv/ Barrierefreie Informationstechnik-Verordnung - BITV]
 
=== France ===
* [https://references.modernisation.gouv.fr/rgaa-accessibilite/ Référentiel Général d’Accessibilité des Administrations - RGAA]
 
===European Union===
* [https://ec.europa.eu/digital-agenda/en/news/proposal-directive-european-parliament-and-council-accessibility-public-sector-bodies-websites Proposal for a Directive of the European Parliament and of the Council] on the accessibility of public sector bodies' websites.


== Tools ==
== Tools ==


=== Firefox extensions ===
* [http://firefox.cita.uiuc.edu/ Firefox Accessibility Extension] by the Illinois Center for Information Technology and Web Accessibility (iCITA)
* [http://firefox.cita.uiuc.edu/ Firefox Accessibility Extension] by the Illinois Center for Information Technology and Web Accessibility (iCITA)
* [[Web developer extension]] for [[Firefox]]
* [[Web developer extension]] for [[Firefox]]
* [[Blank_Your_Monitor_and_Easy_Reading_extension_for_Firefox|Blank Your Monitor and Easy Reading Extension]] for Firefox
* [[Blank_Your_Monitor_and_Easy_Reading_extension_for_Firefox|Blank Your Monitor and Easy Reading Extension]] for Firefox
* [http://www.deque.com/products/worldspace-fireeyes/download-worldspace-fireeyes|FireEye plugin for Firebug]
* [https://addons.mozilla.org/en-us/firefox/addon/wcag-contrast-checker|Color contrast plugin for Firefox]
=== Chrome extension ===
* [https://chrome.google.com/webstore/detail/color-contrast-analyzer/dagdlcijhfbmgkjokkjicnnfimlebcll Color Contrast Analyzer]
* [https://chrome.google.com/webstore/detail/high-contrast/djcfdncoelnlbldjfhinnjlhdjlikmph High contrast]
* [https://chrome.google.com/webstore/detail/chromelens/idikgljglpfilbhaboonnpnnincjhjkd/related ChromeLens]
* [https://chrome.google.com/webstore/detail/see/dkihcccbkkakkbpikjmpnbamkgbjfdcn SEE]
* [https://chrome.google.com/webstore/detail/accessibility-developer-t/fpkknkljclfencbdbgkenhalefipecmb Accessibility developer tools]
=== Accessibility validation tools ===
* [https://chrome.google.com/webstore/detail/accessibility-developer-t/fpkknkljclfencbdbgkenhalefipecmb?hl=en Chrome Accessibility Developer Tooks]
* [[W3C validation]] (for [[HTML in Moodle]], [[CSS]] and [[RSS]])  
* [[W3C validation]] (for [[HTML in Moodle]], [[CSS]] and [[RSS]])  
* [http://wave.webaim.org/ Web accessibility evaluation tool]
* [http://wave.webaim.org/ Web accessibility evaluation tool]
* [http://cynthiasays.com/ Cynthia Says accessibility checker]
* [http://cynthiasays.com/ Cynthia Says accessibility checker]
* [https://chrome.google.com/webstore/detail/axe/lhdoppojpmngadmnindnejefpokejbdd AXE]
* [https://chrome.google.com/webstore/detail/wave-evaluation-tool/jbbplnpkjmmeebjpijfedlgcdilocofh WAVE]
=== Screen readers ===
* [http://www.standards-schmandards.com/projects/fangs/ Fangs – the screen reader emulator] for Firefox
* [http://www.standards-schmandards.com/projects/fangs/ Fangs – the screen reader emulator] for Firefox
* [http://www.nvda-project.org/ NVDA NonVisual Desktop Access] - open source screen reader for Windows  
* [http://www.nvda-project.org/ NVDA NonVisual Desktop Access] - open source screen reader for Windows  
* [http://webaim.org/projects/screenreadersurvey4// WebAIM Screen reader survey] (Predominance of tools, browsers, OSs used by accessibility users)
* [http://www.chromevox.com/index.html ChromeVox] - Available in several languages for Linux, Windows and Mac OS, only on Chrome browser. (Android mobile users can use [https://play.google.com/store/apps/details?id=com.google.android.marvin.talkback TalkBack])


see also this [http://www.w3.org/WAI/ER/tools/complete long list of accessibility tools].
See also this [http://www.w3.org/WAI/ER/tools/complete long list of accessibility tools].
 
See a [http://www.youtube.com/playlist?list=PLmQqs2jGU8Pr7e-3Fz2PoN6AabEkEBRYX live demonstration of a number of accessibility tools].


== Resources ==
== Resources ==
Line 53: Line 133:
* [http://juicystudio.com/article/validity-accessibility.php ''Validity and Accessibility'']
* [http://juicystudio.com/article/validity-accessibility.php ''Validity and Accessibility'']
* [http://www.edtec.unsw.edu.au/inter/support/accessibility/access_vids.cfm Videos showing as student accessing another Learning Management System via Screen Reader software]
* [http://www.edtec.unsw.edu.au/inter/support/accessibility/access_vids.cfm Videos showing as student accessing another Learning Management System via Screen Reader software]
== Common accessibility coding errors ==
; Using CSS for titles, bold and emphasis
: It is generally a good idea to separate a document's content HTML and how it is presented using CSS, however where there are some tags that affect a document's presentation but also contribute to the structure and meaning of the content. These tags should remain in HTML. This includes heading tags <code>&lt;h1&gt;, &lt;h2&gt;, &lt;h3&gt;...</code>, which are used to form the document's hierarchical structure, and <code>&lt;strong&gt;</code> and <code>&lt;em&gt;</code> tags, which are used to add meaning to sections of text.
; Avoid using background images for important information
: Users of non-visual browsers cannot see images. They can read the <code>alt</code> tags of normal images, but background images are not presented like normal images.


== See also ==
== See also ==


* [[:en:Accessibility|Accessibility statement]] - in current Moodle versions
* [[Semantic HTML]]
* [[Semantic HTML]]
* [http://moodle.org/mod/forum/view.php?f=820 Accessibility forum on Moodle.org]
* [[Moodle Accessibility Specification]]
* Using Moodle [http://moodle.org/mod/forum/discuss.php?d=85119 New Accessibility Themes] forum discussion
* See [[Usability FAQ]] for the related concept of usability.
* See [[:en:Usability FAQ]] for the related concept of usability.
* http://moodle.org/mod/forum/discuss.php?d=127807#p559951 (Old, 2009, might not be relevant any more)
* [[:en:Moodle Accessibility Specification]]
* http://moodle.org/mod/forum/discuss.php?d=127807#p559951
* The [http://dev.moodle.org/course/view.php?id=2 Introduction to Moodle Programming] provides some extensive information and discussion on accessibility.
* The [http://dev.moodle.org/course/view.php?id=2 Introduction to Moodle Programming] provides some extensive information and discussion on accessibility.
* [http://www.easy.pro.br/ EASY: Interface Between The Virtual Environment Moodle Learning and People with Visual Impairments]
* [http://www.easy.pro.br/ EASY: Interface Between The Virtual Environment Moodle Learning and People with Visual Impairments]
* [http://www.bbc.co.uk/blogs/bbcinternet/2008/03/homepage_accessibilty.html BBC blog post on how their Web 2.0 homepage was made accessible]
* [http://www.bbc.co.uk/blogs/bbcinternet/2008/03/homepage_accessibilty.html BBC blog post on how their Web 2.0 homepage was made accessible]
* [http://www.bbc.co.uk/accessibility/ BBC Accessibility Help]
* [http://www.bbc.co.uk/accessibility/ BBC Accessibility Help]
* [http://tracker.moodle.org/browse/MDL-7396 Accessibility Compliance in Moodle 1.8]
* [http://tracker.moodle.org/browse/MDL-7860 Compliance with Italian Legislation on Accessibility]
* [https://tracker.moodle.org/issues/?jql=project%20%3D%20MDL%20AND%20status%20%3D%20Open%20AND%20component%20%3D%20Accessibility%20ORDER%20BY%20affectedVersion%20DESC Open accessibility issues on the Tracker]


[[Category:Coding guidelines|Accessibility]]
[[Category:Coding guidelines|Accessibility]]
[[Category:Accessibility]]
[[Category:Accessibility]]
[[es:dev/Accesibilidad]]
[[fr:Accessibilité]]

Revision as of 08:53, 13 December 2016

Websites built with accessibility in mind are flexible in meeting different user needs, preferences and situations. Though these methods can increase usability for everyone who uses the Web they are often legally required to be implemented in a specific effort to prevent discrimination against people with disabilities.

Starting points

These are some readable introductions to accessibility that cover; what accessibility is, why it is important, as well as practical advice.

Moodle Accessibility Collaboration Group

To improve the accessibility/usability of this learning management system, we have established this collaboration group to work together with Moodle developers, administrators, IT professionals, and other interested entities and individuals. We welcome anyone who is interested in improving the accessibility of Moodle to join this group. You don’t need to be a technical guru or accessibility expert to join; however, it is expected that you are familiar with the basics of accessibility and are willing to dedicate a few hours each month to this collaboration effort.

Visit http://collaborate.athenpro.org/group/moodle to join the mailing list.

We meet in regional groups once a month to discuss accessibility priorities for each region. Regions meet at the following times:

  • North America: We meet on the 1st Monday of each month at 10am USA Pacific Daylight Saving Time/5pm UTC. (Time zone converter: http://www.worldtimebuddy.com/)
  • Europe: Looking for leadership and members
  • Asia Pacific: Looking for leadership and members
  • Latin America: Looking for leadership and members

To review past regional meetings or to see up coming meetings visit http://collaborate.athenpro.org/group/moodle/teleconferences/

Moodle-related accessibility coding guidelines

Use CSS, but still use headings, strong and emphasis
It is generally a good idea to separate a document's content HTML from how it is presented using CSS. There are some tags that affect a document's presentation but also contribute to the structure and meaning of the content. These tags should remain in HTML. This includes heading tags

,

,

..., which are used to form the document's hierarchical structure, and and tags, which are used to add meaning to sections of text.

Avoid using background images for important information
Users of non-visual browsers cannot see images. They can read the alt tags of normal images, but background images are not presented like normal images.
Image alt and title attributes
  • An alt attribute is required (even if empty) on all images.
  • If a link is wrapping an <img>, the <img> does not need a title attribute if the link has one.
  • The alt for an image and the title for its surrounding link should usually differ. An image alt attribute provides a text equivalent to an image, whereas a title attribute adds supplementary information about the purpose or action associated with an image link. Simply repeating the same text in alt and title attributes adds little and can be annoying for screen reader users.
Links and buttons should be selectable and easily click-able
  • An image used as an icon for a user to click should be large enough so that the user can click on it easily.
  • Users should be able to navigate to all links and buttons using the keyboard.
  • Generally we should avoid having two buttons/links that achieve the same action in the same area. This can be annoying and confusing for users of screen readers.
Support dynamic interaction with ARIA attributes
Events triggered by AJAX and JavaScript can be less obvious to users of non-visual browsers. ARIA attributes can assist users of such browsers to follow a dynamic change.
Use labels with inputs
Context can easily be lost without a visual presentation. Labels are needed on all input input elements (except button) to describe their purpose in a form. Labels should be unique on a page. Repeated elements should have a unique label that identifies the element within its context.
Use appropriate page titles
A page title is a starting point for a screen reader. Page titles should be unique and should make sense for the page. Avoid generic page titles.
All pages should be navigable using just a keyboard
It should be possible navigate to all points on a page just using a keyboard. Important events triggered by a mouse event should be able to be triggered when the item receives focus through keyboard navigation.
Avoid using colour alone to express meaning
Colour-blind users need additional information to gain meaning if colour is used as the emphasising feature. Also keep in mind that colours can have differing significance in different cultures, so colours should be configurable either through settings or language files.
Use sufficient color contrast when adding color to text. See Tracker ticket MDL 522391
https://tracker.moodle.org/browse/MDL-52391.
Role for button-type links
If a link acts as a button (not forwarding to another page, which is often the case when combined with Javascript), it should declare the role attribute button. Also, as a button is usually triggered by the Space bar, the Javascript should add proper event listeners on the link to accept this key. Read more at Mozilla Developer Network

Web standards, guidelines and legislation

International

USA

UK

See also the Equality Act 2010 Statutory Code of Practice (PDF) for Services, public functions and associations.

Germany

France

European Union

Tools

Firefox extensions

Chrome extension

Accessibility validation tools

Screen readers

See also this long list of accessibility tools.

See a live demonstration of a number of accessibility tools.

Resources

Dive Into Accessibility by Mark Pilgrim
Building Accessible Websites by Joe Clark (online version)

See also