Accessibility in EJ2 JavaScript Dropdown Tree component

24 Jan 20246 minutes to read

The Dropdown Tree component followed the accessibility guidelines and standards, including ADA, Section 508, WCAG 2.2 standards, and WCAG roles that are commonly used to evaluate accessibility.

The accessibility compliance for the Dropdown Tree component is outlined below.

Accessibility Criteria Compatibility
WCAG 2.2 Support Intermediate
Section 508 Support Intermediate
Screen Reader Support Yes
Right-To-Left Support Yes
Color Contrast Yes
Mobile Device Support Yes
Keyboard Navigation Support Yes
Accessibility Checker Validation Intermediate
Axe-core Accessibility Validation Yes
Yes - All features of the component meet the requirement.
Intermediate - Some features of the component do not meet the requirement.
No - The component does not meet the requirement.

WAI-ARIA attributes

The Dropdown Tree component followed the WAI-ARIA patterns to meet the accessibility. The following ARIA attributes are used in the Dropdown Tree component:

Attributes Purpose
role=listbox All list items are contained within the element.
aria-disabled Indicates element is perceivable but disabled.
aria-owns This attribute contains the ID of the popup list to indicate popup as a child element.
aria-haspopup Indicates whether the Dropdown Tree input element has a popup list or not.
aria-expanded Indicates the state of the popup list for Dropdown Tree and the parent node’s expansion status for TreeView.
aria-activedescendent This attribute holds the ID of the active list item to focus its descendant child element.
aria-labelledby This attribute points to the element(s) labeling the element it’s applied to.
aria-decribedby This attribute points to the element(s) describing the one it’s set on.
role=tree All tree nodes are contained within the element.
role=treeitem Specifies the role of each tree node in a selectable TreeView and its containment within the tree.
role=group Specifies the role of each parent node container in the TreeView.
role=checkbox Indicates checkbox control along with treeitem element.
aria-multiselectable Indicates whether the TreeView enables multiple selection or not.
aria-selected Indicates the selected node.
aria-level Indicates the level of node in TreeView.
aria-checked Indicates the current checked state of TreeView checkbox.
aria-label Indicates the contextual message for the TreeView checkbox and Dropdown Tree.
aria-activedescendant Identifies the currently active element when focusing on the TreeView.

Keyboard interaction

The Dropdown Tree component followed the keyboard interaction guideline, making it easy for people who use assistive technologies (AT) and those who completely rely on keyboard navigation. The following keyboard shortcuts are supported by the Dropdown Tree component.

Interaction Keys Description
Alt + Down Opens the popup.
Alt + Up Closes the popup.
Esc(Escape) Closes the popup when it is in an open state.
Arrow Up Goes to the previous item in the popup.
Arrow Down Goes to the next item in the popup.
Arrow Right Expands the current item in the popup.
Arrow Left Collapses the current item in the popup.
Home Goes to the first item in the popup.
End Goes to the last item in the popup.
Enter Selects the focused item in the popup.
Space Checks the current item in the popup.

Ensuring accessibility

The Dropdown Tree component’s accessibility levels are ensured through an accessibility-checker and axe-core software tools during automated testing.

The accessibility compliance of the Dropdown Tree component is shown in the following sample. Open the sample in a new window to evaluate the accessibility of the Dropdown Tree component with accessibility tools.

See also