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Accessibility Guidelines

If you are a programmer and just want to check your code. Please look at the Accessibility Checklist at the bottom of this document.

PREAMBLE

According the Strategy 2017 ILIAS aims to to be "Usable for Everyone" including users with special needs. ILIAS is to be perceivable, operable, understandable and of robust use for all users. ILIAS enables users to locate, identify, access, and operate objects and services provided. These guidelines outline functional accessibility requirements as set out by EN 301 549. V2.1.2 of August 2018. Please consult https://www.etsi.org/deliver/etsi_en/301500_301599/301549/02.01.02_30/en_301549v020102v.pdf EN 301 549 reflects WCAG 2.1 Recommendation Level A and AA. Please consult [https://www.w3.org/TR/WCAG21/] this document is referenced below. For each success criterion there are additional links provided on "Understanding this Particular Success Criterion" and "How to Meet this particular Success Criterion": We encourage developers to look up this information as it is a valuable self-education resource. These guidelines reference both documents. Because ILIAS is rendered in a browser it is categorised as a ‘web page’ by EN 301 549, even though this might not feel right to us. ```

CAVEAT: ILIAS purpose however is to facilitate learning which typically involves content. This content is categorised either as ‘non-web document’ or as ‘web page’. The content is generated by users and beyond the control of ILIAS and thus not covered by these guidelines. Editors and forms allowing users to generate content are to encourage producing accessible output if possible.

HTML-Content rendered by ILIAS shall conform to EN 301 549 / WCAG 2.1 Recommendation Level A and AA.

  1. Controls provide at least one mode of operation that does not require vision.
  2. Visual modes of operation provide features enabling users to make better use of their limited vision.
  3. No mode of operation relies exclusively on the perception of colour, there is at least one additional method of distinction.
  4. If there ever was an auditory mode of operation, there must be at least one mode of operation that does not require hearing.
  5. If there ever was a vocal mode of operation, there must be at least one mode that can be operated without vocal output.
  6. Controls that require manual action provide at least one mode of operation that does not require manipulation or hand strength.
  7. No control has the potential for triggering photosensitive seizures.
  8. We will do our best to accommodate users with limited cognitive, language or learning abilities.
  9. ILIAS can be operated with assistive technology without compromising the privacy of a user.

If proposing a new KS component, one MUST make sure the element conforms with the guideline listed here. If the conformity can only be achieved by the client of the element, one has to state a rule refering back to the corresponding rule in this document

Principle 1: Perceivable

Reference: WCAG 2.1 > 1 / EN 301 549 > 9.1

Information and user interface components MUST be presentable to users in ways they can perceive.

Guideline Text Alternatives

Reference: WCAG 2.1 > 1.1 / EN 301 549 > 9.1.1

One MUST provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language.

Success Criterion Non-text Content

Reference: WCAG 2.1 > 1.1.1 Level A / EN 301 549 > 9.1.1.1

Target group: creator of content, developers for non-text-controls

Understanding Non-text Content

Meeting Non-text Content

All non-text content that is presented to the user MUST have a text alternative that serves the equivalent purpose, except for the situations listed below:

  • Controls, Input: If non-text content is a control or accepts user input, then it MUST have a name that describes its purpose.

  • Time-Based Media: If non-text content is time-based media, then text alternatives MUST at least provide descriptive identification of the non-text content.

  • Test: If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives MUST at least provide descriptive identification of the non-text content.

  • Sensory: If non-text content is primarily intended to create a specific sensory experience, then text alternatives MUST at least provide descriptive identification of the non-text content.

  • CAPTCHA: If the purpose of non-text content is to confirm that content is being accessed by a person rather than a computer, then text alternatives that identify and describe the purpose of the non-text content MUST be provided, and alternative forms of CAPTCHA using output modes for different types of sensory perception MUST be provided to accommodate different disabilities.

  • Decoration, Formatting, Invisible: If non-text content is pure decoration, is used only for visual formatting, or is not presented to users, then it SHOULD be implemented in a way that it can be ignored by assistive technology.

Guideline Time-based Media

Reference: WCAG 2.1 > 1.2 / EN 301 549 > 9.1.2

One MUST provide alternatives for time-based media.

Success Criterion Audio-only and Video-only (Prerecorded)

Reference: WCAG 2.1 > 1.2.1 Level A / EN 301 549 > 9.1.2.1

Target group: creator of content

Understanding Audio-only and Video-only (Prerecorded)

Meeting Audio-only and Video-only (Prerecorded)

An alternative for time-based media or audio description of the prerecorded video content MUST be provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

  • Prerecorded Audio-only: An alternative for time-based media MUST be provided that presents equivalent information for prerecorded audio-only content.
  • Prerecorded Video-only: Either an alternative for time-based media or an audio track MUST be provided that presents equivalent information for prerecorded video-only content.

Success Criterion Captions (Prerecorded)

Reference: WCAG 2.1 > 1.2.2 Level A / EN 301 549 > 9.1.2.2

Target group: creator of content

Understanding Captions (Prerecorded)

Meeting Captions (Prerecorded)

Captions MUST be provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

Success Criterion Audio Description or Media Alternative (Prerecorded)

Reference: WCAG 2.1 > 1.2.3 Level A / EN 301 549 > 9.1.2.3

Target group: creator of content

Understanding Audio Description or Media Alternative (Prerecorded)

Meeting Audio Description or Media Alternative (Prerecorded)

An alternative for time-based media or audio description of the prerecorded video content MUST be provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

Success Criterion Captions (Live)

Reference: WCAG 2.1 > 1.2.4 Level AA / EN 301 549 > 9.1.2.4

Target group: creator of content

Understanding Captions (Prerecorded)

Meeting Captions (Prerecorded)

Captions MUST be provided for all live audio content in synchronized media.

Success Criterion Audio Description (Prerecorded)

Reference: WCAG 2.1 > 1.2.5 Level AA / EN 301 549 > 9.1.2.5

Target group: creator of content

Understanding Audio Description or Media Alternative (Prerecorded)

Meeting Audio Description or Media Alternative (Prerecorded)

Audio description MUST be provided for all prerecorded video content in synchronized media.

Guideline Adaptable

Reference: WCAG 2.1 > 1.3 / EN 301 549 > 9.1.3

One MUST create content that can be presented in different ways (for example simpler layout) without losing information or structure.

Success Criterion Info and Relationships

Reference: WCAG 2.1 > 1.3.1 Level A / EN 301 549 > 9.1.3.1

Target group: creator of content, developer

Understanding Info and Relationships

Meeting Info and Relationships

Information, structure, and relationships conveyed through presentation MUST be programmatically determined or are available in text.

Success Criterion Meaningful Sequence

Reference: WCAG 2.1 > 1.3.2 Level A / EN 301 549 > 9.1.3.1

Target group: creator of content, developer

Understanding Meaningful Sequence

Meeting Meaningful Sequence

When the sequence in which content is presented affects its meaning, a correct reading sequence MUST be programmatically determined.

Success Criterion Sensory Characteristics

Reference: WCAG 2.1 > 1.3.3 Level A / EN 301 549 > 9.1.3.3

Target group: creator of content, developer

Understanding Sensory Characteristics

Meeting Sensory Characteristics

Instructions provided for understanding and operating content MUST not rely solely on sensory characteristics of components such as shape, size, visual location, orientation, or sound.

Success Criterion Criterion Orientation

Reference: WCAG 2.1 > 1.3.4 Level AA / EN 301 549 > 9.1.3.4

Target group: creator of content, developer

Understanding Orientation

Meeting Orientation

Content MUST not restrict its view and operation to a single display orientation, such as portrait or landscape, unless a specific display orientation is essential.

Success Criterion Identify Input Purpose

Reference: WCAG 2.1 > 1.3.5 Level AA / EN 301 549 > 9.1.3.5

Target group: developer

Understanding Identify Input Purpose

Meeting Identify Input Purpose

The purpose of each input field collecting information about the user MUST be programmatically determined when:

  • The input field serves a purpose identified in the Input Purposes for User Interface Components section; and
  • The content is implemented using technologies with support for identifying the expected meaning for form input data.

Guideline 1.4 Distinguishable

Reference: WCAG 2.1 > 1.4 / EN 301 549 > 9.1.4

One MUST make it easier for users to see and hear content including separating foreground from background.

Success Criterion Use of Color

Reference: WCAG 2.1 > 1.4.1 Level A / EN 301 549 > 9.1.4.1

Target group: creator of content, developer

Understanding Use of Color

Meeting Use of Color

Color MUST not be used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element.

Success Criterion Audio Control

Reference: WCAG 2.1 > 1.4.2 Level A / EN 301 549 > 9.1.4.2

Target group: creator of content

Understanding Audio Control

Meeting Audio Control

If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism MUST be available to pause or stop the audio, or a mechanism MUST be available to control audio volume independently from the overall system volume level.

Success Criterion Contrast Minimum

Reference: WCAG 2.1 > 1.4.3 Level AA / EN 301 549 > 9.1.4.3

Target group: creator of content, developer

Understanding Contrast Minimum

Meeting Contrast Minimum

The visual presentation of text and images of text MUST have a contrast ratio of at least 4.5:1, except for the following:

  • Large Text: Large-scale text and images of large-scale text MUST have a contrast ratio of at least 3:1;
  • Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
  • Logotypes: Text that is part of a logo or brand name has no contrast requirement.

Success Criterion Resize text

Reference: WCAG 2.1 > 1.4.4 Level AA / EN 301 549 > 9.1.4.4

Target group: developer

Understanding Resize text

Meeting Resize text

Except for captions and images of text, it MUST be possible to resize text without assistive technology up to 200 percent without loss of content or functionality.

Success Criterion Images of Text

Reference: WCAG 2.1 > 1.4.5 Level AA / EN 301 549 > 9.1.4.5

Target group: creator of content, developer

Understanding Images of Text

Meeting Images of Text

If the technologies being used can achieve the visual presentation, text MUST be used to convey information rather than images of text except for the following:

  • Customizable: The image of text can be visually customized to the user's requirements;
  • Essential: A particular presentation of text is essential to the information being conveyed. Logotypes (text that is part of a logo or brand name) are considered essential.

Success Criterion Criterion Reflow

Reference: WCAG 2.1 > 1.4.10 Level AA / EN 301 549 > 9.1.4.10

Target group: creator of content, developer

Understanding Reflow

Meeting Reflow

Content MUST be presented without loss of information or functionality, and without requiring scrolling in two dimensions for:

  • Vertical scrolling content at a width equivalent to 320 CSS pixels;

  • Horizontal scrolling content at a height equivalent to 256 CSS pixels.

Except for parts of the content which require two-dimensional layout for usage or meaning. Examples of content which require two-dimensional layout are images, maps, diagrams, video, games, presentations, data tables, and interfaces where it is necessary to keep toolbars in view while manipulating content.

Success Criterion Non-text Contrast

Reference: WCAG 2.1 > 1.4.11 Level AA / EN 301 549 > 9.1.4.11

Target group: creator of content, developer

Understanding Non-text Contrast

Meeting Non-text Contrast

The visual presentation of the following MUST have a contrast ratio of at least 3:1 against adjacent color(s):

  • User Interface Components: Visual information required to identify user interface components and states, except for inactive components or where the appearance of the component is determined by the user agent and not modified by the author;

  • Graphical Objects: Parts of graphics required to understand the content, except when a particular presentation of graphics is essential to the information being conveyed.

Success Criterion Text Spacing

Reference: WCAG 2.1 > 1.4.12 Level AA / EN 301 549 > 9.1.4.12

Target group: creator of content, developer

Understanding Text Spacing

Meeting Text Spacing

In content implemented using markup languages that support the following text style properties, no loss of content or functionality MUST occur by setting all of the following and by changing no other style property:

  • Line height (line spacing) to at least 1.5 times the font size;

  • Spacing following paragraphs to at least 2 times the font size;

  • Letter spacing (tracking) to at least 0.12 times the font size;

  • Word spacing to at least 0.16 times the font size.

Exception: Human languages and scripts that do not make use of one or more of these text style properties in written text can conform using only the properties that exist for that combination of language and script.

Success Criterion Content on Hover or Focus

Reference: WCAG 2.1 > 1.4.13 Level AA / EN 301 549 > 9.1.4.13

Target group: developer

Understanding Content on Hover or Focus

Meeting Content on Hover or Focus

Where receiving and then removing pointer hover or keyboard focus triggers additional content to become visible and then hidden, the following MUST be true:

  • Dismissable: A mechanism is available to dismiss the additional content without moving pointer hover or keyboard focus, unless the additional content communicates an input error or does not obscure or replace other content;

  • Hoverable: If pointer hover can trigger the additional content, then the pointer can be moved over the additional content without the additional content disappearing;

  • Persistent: The additional content remains visible until the hover or focus trigger is removed, the user dismisses it, or its information is no longer valid.

Exception: The visual presentation of the additional content is controlled by the user agent and is not modified by the author. Custom tooltips, sub-menus, and other nonmodal popups that display on hover and focus are examples of additional content covered by this criterion.

Principle Operable

Reference: WCAG 2.1 > 2. / EN 301 549 > 9.2

User interface components and navigation MUST be operable.

Guideline Keyboard Accessible

Reference: WCAG 2.1 > 2.1 / EN 301 549 > 9.2.1

All functionality MUST be available from a keyboard.

Success Criterion Keyboard

Reference: WCAG 2.1 > 2.1.1 Level A / EN 301 549 > 9.2.1.1

Target group: creator of content, developer

Understanding Keyboard

Meeting Keyboard

All functionality of the content MUST be operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user's movement and not just the endpoints. This exception relates to the underlying function, not the input technique. For example, if using handwriting to enter text, the input technique (handwriting) requires path-dependent input but the underlying function (text input) does not. This does not forbid and should not discourage providing mouse input or other input methods in addition to keyboard operation.

Success Criterion No Keyboard Trap

Reference: WCAG 2.1 > 2.1.2 Level A / EN 301 549 > 9.2.1.2

Target group: developer

Understanding No Keyboard Trap

Meeting No Keyboard Trap

If keyboard focus can be moved to a component of the page using a keyboard interface, then focus MUST be movable away from that component using only a keyboard interface, and, if it requires more than unmodified arrow or tab keys or other standard exit methods, the user is advised of the method for moving focus away.
Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) MUST meet this success criterion.

Success Criterion Character Key Shortcuts

Reference: WCAG 2.1 > 2.1.4 Level A / EN 301 549 > 9.2.1.4

Target group: developer

Understanding Character Key Shortcuts

Meeting Character Key Shortcuts

If a keyboard shortcut is implemented in content using only letter (including upper- and lower-case letters), punctuation, number, or symbol characters, then at least one of the following MUST be true:

  • Turn off: A mechanism is available to turn the shortcut off;
  • Remap: A mechanism is available to remap the shortcut to use one or more non-printable keyboard characters (e.g. Ctrl, Alt, etc);
  • Active only on focus: The keyboard shortcut for a user interface component is only active when that component has focus.

Guideline 2.2 Enough Time

Reference: WCAG 2.1 > 2.2 / EN 301 549 > 9.2.2

Users MUST be provided enough time to read and use content.

Success Criterion Timing Adjustable

Reference: WCAG 2.1 > 2.2.1 Level A / EN 301 549 > 9.2.2.1

Target group: creator of content

Understanding Timing Adjustable

Meeting Timing Adjustable

For each time limit that is set by the content, at least one of the following MUST be true:

  • Turn off: The user is allowed to turn off the time limit before encountering it; or

  • Adjust: The user is allowed to adjust the time limit before encountering it over a wide range that is at least ten times the length of the default setting; or

  • Extend: The user is warned before time expires and given at least 20 seconds to extend the time limit with a simple action (for example, "press the space bar"), and the user is allowed to extend the time limit at least ten times; or

  • Real-time Exception: The time limit is a required part of a real-time event (for example, an auction), and no alternative to the time limit is possible; or

  • Essential Exception: The time limit is essential and extending it would invalidate the activity; or

  • 20 Hour Exception: The time limit is longer than 20 hours.

Success Criterion Pause, Stop, Hide

Reference: WCAG 2.1 > 2.2.2 Level A / EN 301 549 > 9.2.2.2

Target group: creator of content

Understanding Pause, Stop, Hide

Meeting Pause, Stop, Hide

For moving, blinking, scrolling, or auto-updating information, all of the following MUST be true:

  • Moving, blinking, scrolling: For any moving, blinking or scrolling information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity where it is essential; and

  • Auto-updating: For any auto-updating information that (1) starts automatically and (2) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it or to control the frequency of the update unless the auto-updating is part of an activity where it is essential.

Guideline Seizures

Reference: WCAG 2.1 > 2.3 / EN 301 549 > 9.2.3

One MUST not design content in a way that is known to cause seizures.

Success Criterion Three Flashes or Below Threshold

Reference: WCAG 2.1 > 2.3.1 Level A / EN 301 549 > 9.2.3.1

Target group: creator of content

Understanding Three Flashes or Below Threshold

Meeting Three Flashes or Below Threshold

Web pages MUST not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds.

Guideline Navigable

Reference: WCAG 2.1 > 2.4 / EN 301 549 > 9.2.4

One MUST provide ways to help users navigate, find content, and determine where they are.

Success Criterion Bypass Blocks

Reference: WCAG 2.1 > 2.4.1 Level A / EN 301 549 > 9.2.4.1

Target group: developer

Understanding Bypass Blocks

Meeting Bypass Blocks

A mechanism MUST be available to bypass blocks of content that are repeated on multiple Web pages.

Success Criterion Page Titled

Reference: WCAG 2.1 > 2.4.2 Level A / EN 301 549 > 9.2.4.2

Target group: developer

Understanding Page Titled

Meeting Page Titled

Web pages MUST have titles that describe topic or purpose.

Success Criterion Focus Order

Reference: WCAG 2.1 > 2.4.3 Level A / EN 301 549 > 9.2.4.3

Target group: developer

Understanding Focus Order

Meeting Focus Order

If a Web page can be navigated sequentially and the navigation sequences affect meaning or operation, focusable components MUST receive focus in an order that preserves meaning and operability.

Success Criterion Link Purpose (In Context)

Reference: WCAG 2.1 > 2.4.4 Level A / EN 301 549 > 9.2.4.4

Target group: creator of content, developer

Understanding Link Purpose (In Context)

Meeting Link Purpose (In Context)

One MUST be able to determine the purpose of each link from the link text alone or from the link text together with its programmatically determined link context, except where the purpose of the link would be ambiguous to users in general.

Success Criterion Multiple Ways

Reference: WCAG 2.1 > 2.4.5 Level AA / EN 301 549 > 9.2.4.5

Target group: developer

Understanding Multiple Ways

Meeting Multiple Ways

More than one way MUST be available to locate a Web page within a set of Web pages except where the Web Page is the result of, or a step in, a process.

Success Criterion Headings and Labels

Reference: WCAG 2.1 > 2.4.6 Level AA / EN 301 549 > 9.2.4.6

Target group: creator of content, developer

Understanding Headings and Labels

Meeting Headings and Labels

Headings and labels MUST describe topic or purpose.

Success Criterion Focus Visible

Reference: WCAG 2.1 > 2.4.7 Level AA / EN 301 549 > 9.2.4.7

Target group: developer

Understanding Focus Visible

Meeting Focus Visible

Any keyboard operable user interface MUST have a mode of operation where the keyboard focus indicator is visible.

Guideline Modalities

Reference: WCAG 2.1 > 2.5 / EN 301 549 > 9.2.5

One SHOULD make it easier for users to operate functionality through various inputs beyond keyboard.

Success Criterion Pointer Gestures

Reference: WCAG 2.1 > 2.5.1 Level A / EN 301 549 > 9.2.5.1

Target group: developer

Understanding Pointer Gestures

Meeting Pointer Gestures

All functionality that uses multipoint or path-based gestures for operation MUST be able to be operated with a single pointer without a path-based gesture, unless a multipoint or path-based gesture is essential. This requirement applies to web content that interprets pointer actions (i.e. this does not apply to actions that are required to operate the user agent or assistive technology).

Success Criterion Pointer Cancellation

Reference: WCAG 2.1 > 2.5.2 Level A / EN 301 549 > 9.2.5.2

Target group: developer

Understanding Pointer Cancellation

Meeting Pointer Cancellation

For functionality that can be operated using a single pointer, at least one of the following MUST be true:

  • No Down-Event: The down-event of the pointer is not used to execute any part of the function;

  • Abort or Undo: Completion of the function is on the up-event, and a mechanism is available to abort the function before completion or to undo the function after completion;

  • Up Reversal: The up-event reverses any outcome of the preceding down-event;

  • Essential: Completing the function on the down-event is essential.

Success Criterion Label in Name

Reference: WCAG 2.1 > 2.5.3 Level A / EN 301 549 > 9.2.5.3

Target group: developer

Understanding Label in Name

Meeting Label in Name

For user interface components with labels that include text or images of text, the name MUST contain the text that is presented visually. A best practice is to have the text of the label at the start of the name.

Success Criterion Motion Actuation

Reference: WCAG 2.1 > 2.5.4 Level A / EN 301 549 > 9.2.5.4

Target group: developer

Understanding Motion Actuation

Meeting Motion Actuation

Functionality that can be operated by device motion or user motion MUST also be operable by user interface components and responding to the motion can be disabled to prevent accidental actuation, except when:

  • Supported Interface: The motion is used to operate functionality through an accessibility supported interface;
  • Essential: The motion is essential for the function and doing so would invalidate the activity.

Principle Understandable

Reference: WCAG 2.1 > 3. / EN 301 549 > 9.3

Information and the operation of user interface MUST be understandable.

Guideline Readable

Reference: WCAG 2.1 > 3.1 / EN 301 549 > 9.3.1

Text content MUST be readable and understandable.

Success Criterion Language of Page

Reference: WCAG 2.1 > 3.1.1 Level A / EN 301 549 > 9.3.1.1

Target group: developer

Understanding Language of Page

Meeting Language of Page

The default human language of each Web page MUST be determinable programmatically.

Success Criterion Language of Parts

Reference: WCAG 2.1 > 3.1.2 Level AA / EN 301 549 > 9.3.1.2

Target group: developer

Understanding Language of Parts

Meeting Language of Parts

The human language of each passage or phrase in the content MUST be determinable programmatically except for proper names, technical terms, words of indeterminate language, and words or phrases that have become part of the vernacular of the immediately surrounding text.

Guideline Predictable

Reference: WCAG 2.1 > 3. / EN 301 549 > 9.3

Web pages MUST appear and operate in predictable ways.

Success Criterion On Focus

Reference: WCAG 2.1 > 3.2.1 Level A / EN 301 549 > 9.3.2.1

Target group: developer

Understanding On Focus

Meeting On Focus

When any component receives focus, it MUST not initiate a change of context.

Success Criterion On Input

Reference: WCAG 2.1 > 3.2.2 Level A / EN 301 549 > 9.3.2.2

Target group: developer

Understanding On Input

Meeting On Input

Changing the setting of any user interface component MUST not automatically cause a change of context unless the user has been advised of the behavior before using the component.

Success Criterion Consistent Navigation

Reference: WCAG 2.1 > 3.2.3 Level AA / EN 301 549 > 9.3.2.3

Target group: developer

Understanding Consistent Navigation

Meeting Consistent Navigation

Navigational mechanisms that are repeated on multiple Web pages within a set of Web pages MUST occur in the same relative order each time they are repeated, unless a change is initiated by the user.

Success Criterion Consistent Identification

Reference: WCAG 2.1 > 3.2.4 Level AA / EN 301 549 > 9.3.2.4

Target group: developer

Understanding Consistent Identification

Meeting Consistent Identification

Components that have the same functionality within a set of Web pages MUST be identified consistently.

Guideline Input Assistance

Reference: WCAG 2.1 > 3.3 / EN 301 549 > 9.3.3

One MUST help users avoid and correct mistakes.

Success Criterion Error Identification

Reference: WCAG 2.1 > 3.3.1 Level A / EN 301 549 > 9.3.3.1

Target group: developer

Understanding Error Identification

Meeting Error Identification

If an input error is automatically detected, the item that is in error MUST be identified and the error MUST be described to the user in text.

Success Criterion Labels or Instructions

Reference: WCAG 2.1 > 3.3.2 Level A / EN 301 549 > 9.3.3.2

Target group: developer

Understanding Labels or Instructions

Meeting Labels or Instructions

Labels or instructions MUST be provided when content requires user input.

Success Criterion Error Suggestion

Reference: WCAG 2.1 > 3.3.3 Level AA / EN 301 549 > 9.3.3.3

Target group: developer Understanding Error Suggestion

Meeting Error Suggestion

If an input error is automatically detected and suggestions for correction are known, then the suggestions MUST be provided to the user, unless it would jeopardize the security or purpose of the content.

Success Criterion Error Prevention (Legal, Financial, Data)

Reference: WCAG 2.1 > 3.3.4 Level AA / EN 301 549 > 9.3.3.4

Target group: developer

Understanding Error Prevention (Legal, Financial, Data)

Meeting Error Prevention (Legal, Financial, Data)

For Web pages that cause legal commitments or financial transactions for the user to occur, that modify or delete user-controllable data in data storage systems, or that submit user test responses, at least one of the following MUST be true:

  • Reversible: Submissions are reversible.
  • Checked: Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.
  • Confirmed: A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.

Principle Robust

Reference: WCAG 2.1 > 4. / EN 301 549 > 9.4

Content MUST be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies.

Guideline Compatible

Reference: WCAG 2.1 > 4.1 / EN 301 549 > 9.4.1

One MUST maximize compatibility with current and future user agents, including assistive technologies.

Success Criterion Parsing

Reference: WCAG 2.1 > 4.1.1 Level A / EN 301 549 > 9.4.1.1

Target group: developer

Understanding Parsing

Meeting Parsinghttps://github.com/ILIAS-eLearning/ILIAS/blob/fd01261d7a7fd6aa5f5bebc98b5b43a663be87ef/docs/development/accessibility.md

In content implemented using markup languages, elements MUST have complete start and end tags, elements MUST be nested according to their specifications, elements MUST not contain duplicate attributes, and any IDs MUST be unique, except where the specifications allow these features. Start and end tags that are missing a critical character in their formation, such as a closing angle bracket or a mismatched attribute value quotation mark are not complete.

Success Criterion Name, Role, Value

Reference: WCAG 2.1 > 4.1.2 Level A / EN 301 549 > 9.4.1.2

Target group: developer

Understanding Name, Role, Value

Meeting Name, Role, Value

For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role MUST be determinable programmatically; states, properties, and values that can be set by the user MUST be programmatically settable; and notification of changes to these items MUST be available to user agents, including assistive technologies. This success criterion is primarily for Web authors who develop or script their own user interface components. For example, standard HTML controls already meet this success criterion when used according to specification.

Success Criterion Status Messages

Reference: WCAG 2.1 > 4.1.3 Level AA / EN 301 549 > 9.4.1.3

Target group: developer

Understanding Status Messages

Meeting Status Messages

In content implemented using markup languages, status messages MUST be programmatically determined through role or properties such that they can be presented to the user by assistive technologies without receiving focus.

Accessibility Checklist

This list is prepared to be worked through by developers implementing specific projects. Results from external compliance testing may lead to adapting these phrases. Changes will be subjected to the jour fixe if compliance testing indicates they are erroneous or lacking information. We still hope the following list is helpful in everyday work, please let us know if this is not the case.

Tabbing and Focus

Please manually check your project for tabbing and focus quality:

  1. All functionality must be operable by keyboard, mainly tab, arrow, space or return keys are used. (2.1.1)
  2. Users can move to any control, operate it, and move away again. (2.1.2)
  3. Keyboard focus must be always visible. The element that has focus gets a corona. (2.4.7) Mouse on-active focus must also be visible.
  4. Keyboard control order must be sensible and predictable. The focus moves following the meaning of the content. Moving focus should not jump around unpredictably. (2.4.3)
  5. If an element gains focus it must not
    • transfer users to a different context automatically and without warning i.e. open a new window. (3.2.1)
    • carry out an action automatically i.e. submit a form after a save-button received focus. (3.2.1)

Structure

Check how your project complies with our semantic structures: 6. Write “well formed” HTML, employ HTML according to the specification. The proper functioning of all user agents depends on well formed HTML. (4.1.1). Use validator to verify. Always prefer employing semantic HTML over aria i.e. use HTML lists instead of divs. 7. We use aria landmarks and headlines to furnish ILIAS with semantic structures. Regions of the page and navigation are structured by aria landmarks. User generated content gets structured by headlines. These elements provide programmatically determinable semantic structures to convey information and relationships (1.3.1). 8. Regardless of the visual presentation the DOM order must be presented in a meaningful and usable sequence. When in doubt make the DOM order match the visual order (1.3.2). The screen reader will read the DOM aloud: When the source order matches the visual order, everyone will read the content and interact with it in the same correct order.

Headings, Labels, and Language Attributes

  1. Our headings and labels have to be clear and descriptive (2.4.6). This does not necessarily concern developers and can be handled by language maintainer or the editorial team.
  2. Provide clear and descriptive labels for any form field. If a specific input format is required, specific instructions need to be provided for users. (3.3.2)
  3. Use the language attribute on the HTML element, if the language of the element does not match the language of the parent element. Screen readers change pronunciation accordingly. (3.1.1)

Colour and Contrast

Please check your project for colour and contrast issues: 12. Use of colour as a visual cue is only ok if its message is additionally communicated by other means, too. (1.4.1.) 13. Ensure contrast requirements are met. Use for example Wave or Lighthouse to verify.

Alt-Texts and aria labels

Please check if your project labels the GUI for all target groups: 14. Non-text elements like icons, images, graphs and the like must have an alt-attribute (1.1.1). If the non-text element is merely decorative this attribute may be empty. 15. Glyphs are done in spans which cannot bear alt-texts but carry a link-tag, which must have an aria-label.
16. If labels are used with interactive elements, always use Wave to check whether labeling requirements are met.