Accessibility in Blazor MultiSelect Dropdown Component
29 Nov 20245 minutes to read
The Blazor MultiSelect Dropdown component has been designed, keeping in mind the WAI-ARIA specifications, and applies the WAI-ARIA roles, states, and properties along with keyboard support. This component is characterized by complete keyboard interaction support and ARIA accessibility support that makes it easy for people who use assistive technologies (AT) or those who completely rely on keyboard navigation.
The Blazor MultiSelect Dropdown 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 Blazor MultiSelect Dropdown component is outlined below.
| Accessibility Criteria | Compatibility |
|---|---|
| WCAG 2.2 Support |  |
| Section 508 Support | |
| Screen Reader Support | |
| Right-To-Left Support | |
| Color Contrast | |
| Mobile Device Support | |
| Keyboard Navigation Support | |
| Axe-core Accessibility Validation | |
- All features of the component meet the requirement.
- Some features of the component do not meet the requirement.
- The component does not meet the requirement.WAI-ARIA attributes
The Blazor MultiSelect Dropdown component uses the Listbox role, and each list item has an option role. The following ARIA attributes denotes the MultiSelect state:
| Properties | Functionalities |
|---|---|
| aria-haspopup | Indicates whether the MultiSelect input element has a popup list or not. |
| aria-expanded | Indicates whether the popup list has expanded or not. |
| aria-selected | Indicates the selected option. |
| aria-readonly | Indicates the readonly state of the MultiSelect element. |
| aria-disabled | Indicates whether the MultiSelect component is in disabled state or not. |
| aria-activedescendent | This attribute holds the ID of the active list item to focus its descendant child element. |
| aria-owns | This attribute contains the ID of the popup list to indicate popup as a child element. |
Keyboard interaction
You can use the following key shortcuts to access the Blazor MultiSelect Dropdown without interruptions:
| Keyboard shortcuts | Actions |
|---|---|
| Arrow Down | Sets focus at the first item in the MultiSelect when no item is selected. Otherwise, moves focus next to the currently selected item. |
| Arrow Up | Moves focus previous to the currently selected one. |
| Page Down | Scrolls down to the next page and set focus to the first item when popup list opens. |
| Page Up | Scrolls up to the previous page and set focus to the first item when popup list opens. |
| Enter | Selects the focused item, and when it is in an close state the popup list opens. |
| Tab | Focuses on the next TabIndex element on the page when the popup is closed. Otherwise, closes the popup list and remains the focus of the component. |
| Shift + tab | Focuses on the previous TabIndex element on the page when the popup is closed. Otherwise, closes the popup list and remains the focus of the component. |
| Alt + Down | Opens the popup list. |
| Alt + Up | Closes the popup list. |
| Esc(Escape) | Closes the popup list when it is in an open state and the currently selected item remains the same. |
| Home | Sets focus to the first item. |
| End | Sets focus to the last item. |
Ensuring accessibility
The Blazor MultiSelect Dropdown component’s accessibility levels are ensured through an axe-core software tool during automated testing.
The accessibility compliance of the MultiSelect Dropdown component is shown in the following sample. Open the sample in a new window to evaluate the accessibility of the MultiSelect Dropdown component with accessibility tools.