Timeline Accessibility
Out of the box, the Telerik UI for ASP.NET Core Timeline provides extensive accessibility support and enables users with disabilities to acquire complete control over its features.
The Timeline is compliant with the Web Content Accessibility Guidelines (WCAG) 2.2 AA standards and Section 508 requirements, follows the Web Accessibility Initiative - Accessible Rich Internet Applications (WAI-ARIA) best practices for implementing the keyboard navigation for its component role, provides options for managing its focus and is tested against the most popular screen readers.
WAI-ARIA
This section lists the selectors, attributes, and behavior patterns supported by the component and its composite elements, if any.
The Timeline component features two very different modes of rendering: vertical and horizontal. Those two modes require two very different approaches in terms of WAI-ARIA implementation:
- Horizontal Timeline: should be implement as a
role: tablistcomponent. - Vertical Timeline should be implemented as a collection of Buttons. Each event on the Timeline is a Button.
Horizontal Timeline
| Selector | Attribute | Usage |
|---|---|---|
.k-timeline.k-timeline-horizontal .k-timeline-track-wrap .k-timeline-scrollable-wrap | role=tablist | Indicates the tablist role for the ul element of the Timeline. |
.k-timeline.k-timeline-horizontal .k-timeline-track-item:not(.k-timeline-flag-wrap) | role=tab | The tab li element. |
.k-timeline.k-timeline-horizontal .k-timeline-track-item[aria-selected=true] | aria-describedby | The current selected tab element must be described by its tabpanel. |
.k-timeline.k-timeline-horizontal .k-timeline-track-item:not(.k-timeline-flag-wrap).k-focus | aria-selected=true | Announces the selected state of the tab. |
.k-timeline.k-timeline-horizontal .k-timeline-flag-wrap | role=none | The flag wrap elements must have its semantics removed. |
aria-hidden=true | The flag wrap should not be present in the accessibility tree. | |
.k-timeline.k-timeline-horizontal .k-card:not(:empty) | role=tabpanel | The content div of the tab. |
aria-label | Refers to the tab element that controls the panel. | |
.k-timeline.k-timeline-horizontal .k-timeline-event[style='transform: translate3d(0px, 0px, 0px);'] .k-card | tabindex=0 | The current tab panel elements must be focusable, so that its contents would be announced. |
.k-timeline-arrow | aria-hidden=true | Introduce aria-hidden attribute for the scrollable buttons. The buttons are not included in the tabsequence. |
Vertical Timeline
| Selector | Attribute | Usage |
|---|---|---|
.k-timeline.k-timeline-vertical .k-card | role=button | The items in the vertical Timeline are represented as buttons. |
aria-describedby=.k-timeline-date id | The items in the vertical Timeline are described by their date elements. | |
aria-live=polite | The items in the vertical Timeline must be marked as live regions. | |
tabindex=0 | The items in the vertical Timeline must be focusable. | |
.k-timeline.k-timeline-vertical .k-collapsed .k-card | aria-expanded=false | When collapsed, the items in the vertical Timeline must have their aria-expanded attribute set to false. |
.k-timeline.k-timeline-vertical .k-timeline-card:not(.k-collapsed) .k-card | aria-expanded=true | When expanded, the items in the vertical Timeline must have their aria-expanded attribute set to true. |
Resources
WAI-ARIA specification for tablist
WAI-ARIA practices: TabList example
Section 508
The Timeline is fully compliant with the Section 508 requirements.
Testing
The Timeline has been extensively tested automatically with axe-core and manually with the most popular screen readers.
To report any accessibility issues, contact the team through the Telerik Support System.
Screen Readers
The Timeline has been tested with the following screen readers and browsers combinations:
| Environment | Tool |
|---|---|
| Firefox | NVDA |
| Chrome | JAWS |
| Microsoft Edge | JAWS |
Test Example
To test the Timeline component, refer to the Timeline Accessibility Demo.
Keyboard Navigation
For details on how the Timeline keyboard navigation works, refer to the Timeline Keyboard Navigation article.